Dirtbag Backyard Concrete Counter Method
Here’s how I’ve come to build concrete countertops in my backyard. This is basically as Cheng does it, but I hope some of my less refined tips could help some aspiring counter makers!
This is a counter for a job–a simple little utility room counter with a polished surface, an undermount sink and a simple little inlay.
Unless you have a bombproof table ready to go you’ll need something to support your molds, and your piece. (photo “base”) I make a 2×6 base, 12″ oc, just wider than my form with the sides screwed to it. Run all thru your table saw first so they’ll all be the same — and none will stand proud and put a bump in your mold. I screwed the legs of my horses to the floor (of my shed here…) and then perflectly leveled the base, shimmed and screwed it to the horses. If you don’t have/build a base to support the form/piece, you’ll come out with something as such–bowed, twisted, not flat. It will then break when you put it on your flat/level cabinets and substrate…
First I work on the base of the form, and then anything IN it, before doing the sides.
I build my forms from melamine particleboard. There’s a spot in town here that makes the stuff and they sell outs for 4$ a 4×8. I Buy 1″ and 3/4″ Use 1″ for the bottom of the mold (top of the piece) and 3/4″ for the sides. Then, stacked each-on-each you get 1 3/4″ for your sink knockout. 1 3/4″ is as thin as I rec. going. I’ve done a few 1 1/2″ thickness and they break..
The photos will also show I make a router template from hardboard for the sink knockout. I don’t use the templates that come with the sinks b/c usally they expose too much of rim. I put the sink upside down on it, reach in and trace the outline of the bowl(s) then cut out with jigsaw and clean up with sander. Use that with flush cutting bit to make duplicates in 3/4″ and 1″ to stack for the sink knockout. Wrap edges with packing tape–duct tape also makes a nice texture and is slippery when it comes to unforming.. Drill some pilot holes thru the whole knockout and screw it where you want it to the face of the form. Use 100% silicone to seal wherever parts of the form meet. Strike it off with your finger and it makes a perfect beveled edge around the whole form and seals it watertight.
The knockouts for the faucet are 1″ sch 40 pvc with a slot cut in, then wrapped with duct tape. Drill right into the base of the form with a spade bit the same OD as your pvc and just push them into it. (see photo) If the counter is thicker than the stems on your faucet, you’ll have to make a recess in this area for the hardware as well.
Installment 2 next.
“Research is what I’m doing when I don’t know what I’m doing…”
Edited 2/17/2008 10:33 pm by Waters
Replies
Now it's time for an inlay.
Anything you want in the surface of the counter can now be placed in the mold. Use a thin film of silicone to anchor it to the melamine. Here I've just crosscut some sections of copper tubing, about 1/2" and glued them in the form with silicone.
Next is the form with the sides screwed on, all sealed with silicone and ready to go. By the way, pre drilling your melamine particle board for screws is good because it will not dimple and push the form pieces apart anywhere. The sides are about 1/16" high/wider than the 1 3/4" the counter will be. This helps with screeding.
Now the mix. For this counter, I didn't bother with the 'from scratch' mix outlined in the book. The HD sells a 'crack resistant' 5000 psi cc that has reducer and fiber reinf. in it and it works great. The agg in it is crushed but reasonably colorful. I added the requisite amount of 'slate green' dry pigment and mixed up until 'thinks looked right.' I rec. wetter than Cheng's 'lumpy oatmeal' slump. You'll not be able to vibrate it properly, especially if you're a dirtbag like me, and don't have the resources for the right tools, and you'll end up with a counter that looks like swiss cheese. You cannot properly vibrate a counter with a palm sander, or by rapping on the edges of the form...
Installment 3 coming...
"Research is what I'm doing when I don't know what I'm doing..."
Once your mix is right you can fill the mold, about half way. Work it into the bottom of the mold with your fingers.
Now you want to vibrate the he** out of it. My preferred backyard method is my rotary hammer. I put the chisel in it, put in on hammer, and go around the base buzzing like crazy. You can really see the concrete settle and the bubbles come up. I've never vibrated too much. I use my multimaster (another great excuse to buy one!) with a piece of aluminum screwed into it to vibrate all around the edges of the form, which will be very visible on the counter.
I bet you've been wondering how I reinforce the countertop?
Now I place pencil rod (only) in the form, the long way, 6-8" oc. It's enough.
Vibrate a little more to settle the rod a hair.
Installment 4 coming...
"Research is what I'm doing when I don't know what I'm doing..."
Once your rod is in place, now you can fill the rest of the form.
Fill it all the way, then vibrate again, then screed it off in a sawing motion with a sharp, straight board. I like a piece of the melamine I use for the sides.
Now, it's basically done. Go get a beer (if you didn't already ) and wait about 4 days. Keep the piece relatively warm and moist. Tent it with plastic if it's hot and dry.
Getting it out of the form is pretty basic. remove the sides first, then take a stone to any of the rough or 'titty' parts on the bottom of the counter. It is those points that will make it break when you flop it flat on the cabinetry.
Then I slide it over to one side of its base, put some type of foam or otherwise soft material with some give under it to support it and FLIP it over. Now pry gently with bars, shims, your fingers or whatever and POP! The moment of truth!
Now cut out the sink KO by drilling pilots and cutting out with your jigsaw in 4 directions.
Now you're excited. The piece should be glassy smooth, maybe some pits here or there but better than you expected! This one has some ghosting from the pencil rod, and quite a few little pits--see! should have gone wetter on the mix!
Next I'll detail how i grind and polish, and how I fill pits or voids. And on to installing this counter.
I hope this interests some of you!"Research is what I'm doing when I don't know what I'm doing..."
Looks great. Keep it coming.I'm curious how you get the chamfer or round over on the edges.
That bead of silicone that seals up the mold--when you run your finger over it it makes a nice fillet shape that's reflected in the concrete.
I know there are premade forms you can buy, to create edge profiles and whatnot, but I've not used them.
I've made curved edges by using flexible materials like aluminum or hardboard for those forms."Research is what I'm doing when I don't know what I'm doing..."
Keep 'em coming!
Very interesting...
A few quick Qs:
1) What is pencil rod?
2) was the reason for putting the saw cuts in the faucet holes (PVC pipe) to make the pipe diameter smaller, or something to do with making it easier to get out of the mold.
In a way your "article" is more interesting than reading in a mag or whatever since yours is done in the real world where we don't have fancy tools like $1800 tablesaws and special purpose concrete vibrators...
Pencil rod is a steel rod appx. 1/4 inch dia. used to hang black iron for hung clgs. . Typically used on commercial jobs. Acoustic supply house should have it.
Rich
A few quick Qs:
1) What is pencil rod?
That's a thin metal rod--comes in 20' lengths from the mason supply place. I believe it's used with a foundation wall forming system--holds the forms together thru the wall...
2) was the reason for putting the saw cuts in the faucet holes (PVC pipe) to make the pipe diameter smaller, or something to do with making it easier to get out of the mold.
Cutting a slot lengthwise makes them flexible in their diameter, so you can easily shove them into their hole in the face of the form, and get them out. The duct tape serves to increase their diameter a little to get some 'slop' for your faucet, and it's slippery when it comes time to pull them out of the counter. I just grab them with a channel lock and twist and pull. You can reuse them too. Cheng shows cylinders cut from wood, and also tubing like this with slots, but he screws them to the mold. Drilling a hole into the mold seems to work a lot better for me. But, if you need a disk to knockout more for your faucet stem nuts, then the screw, thru the disk and the cylinder works.
In a way your "article" is more interesting than reading in a mag or whatever since yours is done in the real world where we don't have fancy tools like $1800 tablesaws and special purpose concrete vibrators...
I hope so! I take so much good info from this site and it's members. This is the only thing that I've really mastered (in some degree) that I thought I could give back."Research is what I'm doing when I don't know what I'm doing..."
Looks good, keep the pics coming.
jt8
"The unfortunate thing about this world is that good habits are so much easier to give up than bad ones." -- Somerset Maugham
Off to work (other work--hangin' doors today) but I'll have more posts and more photos soon.
Coming:
Grinding and polishing
Filling voids and pits
sealing and waxing
transport
installation"Research is what I'm doing when I don't know what I'm doing..."
That sure is a lot of work. Maybe I'm benighted, buy what exactly is the big deal about concrete countertops?. I learned long ago there are two types of concrete -- concrete that has cracked, and concrete that is going to crack. Cracks are OK in a driveway. Do they add rustic charm to a countertop?
"That sure is a lot of work. Maybe I'm benighted, buy what exactly is the big deal about concrete countertops?. "
You are so right. It's one caveat I wanted to address at some point in my thread. This is not a money maker--especially when folks look at it and you can do granite or tile for about the same $ or less.
It's a lot of work--and boy can you go wrong. One wrong step early in the process and it's all for naught.
So why do I do it? It affords me a chance to (try to be) be creative or artful. There are so many forms the counter can take. So many personalized details to add to it. It's really just a side thing for me, but I've found ways to speed up the process and actually make some decent $ doing it.
The material costs are next to nothing... That and it's pretty 'green.' You're not depleting any measurable natural resource to build a counter. All my molds and whatnot get reused or recycled with my other wood debris for hog fuel.
"I learned long ago there are two types of concrete -- concrete that has cracked, and concrete that is going to crack. Cracks are OK in a driveway. Do they add rustic charm to a countertop?"
For some they certainly do, when the rest of the counter is a wonder to look at--rather than just a smooth grey slab with a bunch of cracks in it. But that said, I build counters for people who want something artful and funky--not sanitary and perfect. Something that when they have folks over, they're like, "What the?" "What is that made of?""Research is what I'm doing when I don't know what I'm doing..."
Do you seal the tops with anything?
I've been wanting to make a CC top for a while, now if I could just find the time...
Mine are sealed first with your basic tile/grout sealer, then waxed and buffed shiny.
I have to look into polyurethane, or expoxy finish soon though. I have a lady I did counters for that wants a non-porous finish.
Any thoughts, anyone?"Research is what I'm doing when I don't know what I'm doing..."
This, as many have said, is a great thread! Somethings occurred to me:with the shadowing of the pencil rod, have you considered using this to your advantage, incorporating it as a design element? Also I'd like to see a picture of how the copper inlay turned out. Again, very good thread.Kevin
No I don't think I'd want the ghosting as a design element... usually your reinforcement goes in in a pretty boring square or linear pattern...
As for inlay -- sneak preview:"Research is what I'm doing when I don't know what I'm doing..."
7% alcohol on that beer? You left coasters get all the good stuff.
<7% alcohol on that beer?>
Hey! Good attention to detail!
Forrest
Oh yes!
And my neighbor is the lead brew guy for a local brewpub called the "steelhead." I have a rye IPA of his, from his home brew stock, in my glass at this moment!
My favorite beer out here is one made in a little dinky town in NE Oregon. The brewery is called "Terminal Gravity" and they make an IPA that is head and shoulders above all the rest.
There are at least 4 brew pubs in town that are all about making the IPA with the most explosive hop 'action' and highest acl content... Can't really enjoy more than one of those...
"Research is what I'm doing when I don't know what I'm doing..."
Great how to and I like how u keep it simple. Keep them pictures coming. Thanks
"I hope this interests some of you!"Of course we're interested! Thanks for the tutorial! Bob's next test date: 12/10/07
Great thread and great pics!
First time I ever saw a 'crete top, it was in the part of the big Kohler plumbingware display area they set up at each year's big Builders Show, in the high-end part where they showcase their Canac cabs and Ann Sacks tile.
In this one I saw, the mix must have had white colorant in it, and the maker had used some aggregate with garnet and granite stones, plus some chunks (about the size of boullion cubes) of stained glass in rich dark blues and reds.
They either used a terazzo grinder on it, or did a lot of work with smaller hand grinders, because the surface was machined down pretty darned flat. The combo of the white cement and sand, plus the garnet, granite, and glass, was stunning.
First one I ever tried, I thought a lot of knocking on the forms and table legs with a hammer would suffice. Certainly generated a lot of bubbles!
Wrong! Threw that one out, and still had to grout with epoxy even when using a big ol' vibrator to shake the setup the second time.
I liked the technique Buddy Rhodes showed in his FH article a while back, which was about making fireplace surround panels. Buddy just made the primary mix like bread dough and pressed it in, no vibration, planning for a surface with a bunch of voids.
Then, with his slurry mix in a complementary color, he did the fill work, followed by the finishing with grit, and the coating. Cool.
View Image
"A stripe is just as real as a goddamn flower."
Gene Davis 1920-1985
Looking Good. For vibration I have used back massagers , the big ones with a thumping action , as well as using a "bushing hammer" in my hammer drill just to provide more surface area at the working end of the hammer. Did make a small "pencil" vibrator that looked like the ones used on commercial work by taping a piece of stiff rubber hose with a bolt stuffed in the end to the working end of the back massager. Worked fairly well for settling the field of the bigger pieces I did. I haven't done any counter tops that I could cast separate. My work has all had to be done in place for hearths and counters in and around BBQ's outside. I do use the Sacrete mix.
They can't get your Goat if you don't tell them where it is hidden.
My first counter job--a really big kitchen--too big for my first job really!--the client and I laughed about 'vibrators.'
She said she might have one that would work.
;-)
There is actually a concrete vibrator att. for the multimaster. That's what got me on that tool for vibing. It was too expensive, of course. I tried making one out of a stick of pex, with an end in it, epoxied to an aluminum splint and a mounting hole... that didn't work...
The rotary hammer really does it.
Yeah, I really want to cast in place too. The first counters I ever did 10 years ago, were our own in our other house, cast in place and I had an expert helping and finishing. I think I might be able to pull it off now!"Research is what I'm doing when I don't know what I'm doing..."
Here is a tech support question:
I have made the mold for my kitchen counter. It is approximately 2 feet by 5 1/2 feet, with two corners cut out to fit around stuff. When installed, it will be fully supported underneath by 3/4 ply.
Due to design considerations ("design considerations" is a great way to say "lack of planning") I am making it 1 3/4 inch thick, although I would have preferred to make it 2 inches. As a result, it is difficult to keep all the reinforcement away from the surfaces. I have cut remesh to fit, and temporarily blocked it up 1" off the surface of the form. By the time I lay a couple of pieces of #3 rebar on top of this, I am getting pretty darn close to the top of the mold (i.e. the under surface of the countertop). I am worried about weakening things by having the steel so close to the (under) surface.
On the other hand, I am trying to avoid ghosting by keeping the metal at least 1" from the counter's top surface.
Can I go with just the mesh, and forget the rebar?
Any ideas?
Thanks for the help. I am pouring tomorrow.Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.
-Groucho Marx
That thin I would forget the rebar--or only use the rebar.
I think, that in a thinner counter, the metal just makes weak spots.
I might advise you to only use the rebar--the long way--as I showed with my pencil rod.
I put 'hog panel' which is a galv. metal mesh somewhat like remesh in a couple early counters and they broke at just about ever cross section--you know--perpendicular to the length of the counter.
You're trying to support the counter thru it's length--not it's width. So I only go with reniforcement lengthwise.
My 2 cents.
Ponytl?"Research is what I'm doing when I don't know what I'm doing..."
Frosty morning."Research is what I'm doing when I don't know what I'm doing..."
I'll see if I can find some 1/4" rebar tomorrow, before I pour, then lay a few of them across lengthwise.
Those copper pipe insets look great -- looks kinda like a diagram of the solar system.
I had all sorts of great ideas for things to use as insets, but the wife ko'd them. Hey, she's the one who's gonna be working there, so I guess I gotta go along.
I'll post pictures at some point.
Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.
-Groucho Marx
i've used everything... rebar... all thread... and one of my fav's grid wall... the stuff you see in store displays or on pallet rack about 5/16 rod welded into a 3" grid... i do prefer the small rebar over anything... it just seems right...
i think if it's well supported the steel in the concrete is only help'n while you are putting it into place... once in place and well supported i think the steel has already done it's job...
for the record... i've never had ghosting... might be the white portland i use where it just doesn't show? just don't know...
i do think... thinner the counter the longer i'd leave it in the mold... maybe up to 3-4weeks... and for what little it'd cost i'd up the portland in the mix... and make sure i wasn't use'n round rock... i like the sharp pointed stuff...
just a few thoughts...
i'm still learning with everything i cast... i have several what i consider standard molds... sheet metal (20ga) 2" deep and 25" wide x 10ft long... i can block em to size... i don't get the supper slick surface on the metal that i do on the lexan...
but i think i'll do the same thing.. same mix...(by weight) but i'll get different results... not bad just different... which i guess is part of the fun... not knowing what you'll get...
p
Thanks to Waters and Ponytl for input on my project.
I just finished pouring my countertop. In the end, I used 3/8 rebar, lengthwise. I kept it an inch away from the countertop surface.
I tried vibrating with a bladeless Sawzall (a Cheng suggestion). It was wimpy. I then tried your idea and attacked it all around with the rotary hammer- this was DEFINITELY the tool for the job. The oatmeal started to flow so much I couldn't believe it.
By the way, the outlines of the rebar are already showing in the bleed water. Maybe different patterns of water escaping affects ghosting? Just an idea.
Time for a malt beverage.
Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.
-Groucho Marx
Is there some reason why a concrete vibrator can't be used? Bob's next test date: 12/10/07
Good question.
Basically the thing is too big and agressive for the task. You end up with concrete everywhere because you can't submerge the thing.
Also, if you're casting in molds, you get these wierd swirlies where the vibrator touched the surface of the mold...
I rented a stinger for one job.
The cheng guys show a monster stinger with flat sides clamped to their casting table. They buzz the hell out of the whole table, mold and piece to vibrate.
I thought I could sort of do this by drilling some 3" holes in the cribbing that my 6 different molds were sitting on, and sticking the stinger in the holes (I can't help but think of the responses as I write this... is that a reflection on me? or the rest of you gutter brains?) and vibrating that way... Basically it just shook everything loose everywhere...
The rotary hammer works great--pinpoint and the perfect 'buzz.'"Research is what I'm doing when I don't know what I'm doing..."
I had an old recliner with a vibrating back . I thought about pulling the pack out it out for just that purpose before "recycling' the recliner. Decided it would be just one more piece of junk I would never deal with though. Keep thinking : Should have saved it. Nice little motor with a off balance weight on it, all set up for screwing to the sides or bottom of a frame.
They can't get your Goat if you don't tell them where it is hidden.
got any photos of your 'cast in place' pieces?"Research is what I'm doing when I don't know what I'm doing..."
Nothing that is a close up. What I have is a hearth and not a counter. Give you some idea though. #99 and #01 were taken to help an archy make a decision as to th skirt material . The others were taken just at move in day . Regular sack mix, fortified with an extra shovel worth of cement and colored black. Each mixer full was done using exactly the same quantities of each component. Had the strangest occurrence with this one. It was very slow drying so I stayed at the site until 11 pm to finish it. Still not as perfect as I wanted so I returned very early am to "burnish " the edges and polish the top just a bit if I could. When I got there in the morning it had a cone shaped hole in it just to the right of the score mark in the pic. Surrounding the hole were the bits of mud from the hole (it looked like an explosion had happened beneath the surface). After warming up with some choice words I worked to repair the damage. As I did so I noticed small bits of a brown fiber like material , looking closer I realized I was looking at seeds.
I am convinced that some where along the line a small seed pod got into the mix. A seed pod of the type that when warmed and dampened expands or explodes with enough force to spread the seed out over a small area. Craziest thing I ever saw. It left a cone shaped crater about 3/4" deep and the same in diameter across the top. I wasn't able to completely fix the divot as the mud had set up too much. Looking closely one can still see a small roughened area where the seed had exploded. Finish is done with steel trowel .
They can't get your Goat if you don't tell them where it is hidden.
Oh the black stuff for the skirt--for sure!
I like it a lot (your hearth) mod but organic. The woodwork very nice too.
What's with the floor? Is that CC too? Looks like hardboard almost?
The seed pod thing... that's funny. Sure it wasn't a squirrel?
;-)
Thanks for showing. I have some projects around my own place--I want to cast my own stairtreads and grind and polish them for the front steps--and some ledges up the sides and then do a stone facade around all."Research is what I'm doing when I don't know what I'm doing..."
Floor is color in concrete. With 1 x 6 CVG Fir divider strips. Radiant slab. Unfortunately the archy went with the CVG Fir to match th rest of thE house. I liked the black as well
They can't get your Goat if you don't tell them where it is hidden.
I have to figure out how to send some pics, I'll try tomorrow. We did a big counter recently, poured in place. The concrete came all the way to floor on two sides, entering the kitchen it looks like a huge block of crete sitting on the floor. We left the rebar stick out on one edge too, rounded them with grinder. Too much to explain it all I'll have to send pics. It was FUN.
Not so fun though when our helper sat his italian hoagiie on it before it was sealed. He's no longer with us. The oil soaked in right through the bag, left nasty stain
Glad to see your post, thought we were doing it wrong, sacrete mix and all. Havent tried polishing one yet, we've just been troweling them best we can and acid etching for color. Like you said the people who want one don"t want perfection, thats the point. This one even had a big honey comb on one of the sides that went to the floor, but when we told the customer we were planning to fill them he said no way. It really did look cool, some rebar exposed too.
Anyway I'll try to send pics, if anyones interested ,but just got computer still don't know how to use one yet.
later.
Love to see it!
Thanks.
On posting pics--use the search function for "Irfanview" which is a free download program to shrink your photos so all can download them easily.
Just figured this out myself--most of my photos are taken 'small' though so I don't have to resize them."Research is what I'm doing when I don't know what I'm doing..."
Hey a quick question, I have done a few cast in place kitchens and was wondering if you have done any outdoor kitchens, i.e. BBQ areas. I thought it would be a perfect place for concrete countertops on brick cabinets. Then I became hesitant when I read in a discussion with Cheng that he discouraged it because of the effects of nature (expansion and contraction). What Say You Thanks for your time and knowledge - great stuff - Scott
I have done a couple outdoor BBQ, seating areas, and counters. All cast in place. As far as I know to date they have all survived quite nicely. I am in Ore. so freeze thaw cycles are limited but do happen.
They can't get your Goat if you don't tell them where it is hidden.
A couple of pointers that I'll toss out:
1) If anyone will be doing a lot of these, consider using your own mix instead of a bagged mix. Reason? Replication. Can you make me a top like Martha's? Sure, because I know what any how much of each ingredient is on the mix. Bagged mixes can change over time, or be discontinued.
My mix works out to about a 7-sack mix equivalent. Never had a slab snap or crack.
Keep a notebook of your work. Formulas, pigments used, cure time, sealer, etc. Always mix a bit more than you need and cast that leftover mix in a small form, say 6" square by 1" thick. Sounds silly, but it'll give you a reference for future color selection.
2) Several references have been made to white portland. That's the ticket to getting a "clean color". Gray portland and regular sand will muddy the color of any pigment. That's not a bad thing, it's very earthy, you get some great results. But when you need to cast a canary yellow slab (yup, been there, done that) using white portland and white silica sand will allow thew yellow pigment to shine.
3) Ghosting. If vibrating after you set your rebar or pencil rod, the vibrating can casue the rod to settle within the mix. That's giving you the ghosting. Tie the rebar off to iteslf in a grid, then after placing your first layer of concrete, set the rebar and use wire ties to tie the rebar grid off to screws screwed into the form. Then place the remainder of your mix.
Vibrate, and the tied off rebar will not sink to the bottom of the form (towards the top of the slab) and ghost.
4) Vibrating. You can vibrate too much. Too much vibrating will cause the aggregate to settle, giving you an uneven composition throughout, and weakening the slab. That could be a contributing factor in your failed slabs.
The rotary hammer works great. I also have a scavenged washing machine motor with an eccentric weight screwed to my casting table. Don't screw it to the form or you'll tear the form apart. Let the table shake the form. Only takes a minute or two and the results are consistent.
5) Why concrete? Good question. It's liquid stone. You can do things with concrete you can't do with natural stone. Some people get it, some don't. Different strokes.
6) Sealing. You can use a film sealer or a penetrating sealer. Film sealers are bulletproof in regards to stain prevention, but they make the countertop a bit less user-friendly. Meaning to a certain extent, you have to baby the countertop. Taking a hot pot off the cooktop or out of the oven and placing on a film-sealed top could cause the film to discolor or lift from the slab. Bad bad bad.
I may use a film sealer in some bathroom countertops where the top doesn't take the abuse that a kitchen countertop might.
Mostly I'll use a penetrating sealer, Sealer's Choice by Aquamix. Unlike some of the things mentioned in this thread, it's food-safe and is used in the restaurant industry. It's pricey, but a little goes a long way. Wipe on, let sit for 5 mihnutes, wipe off. Repeat two more times. Then buff with a coat of food-safe paste or some other type of food-safe wax.
The wax protects the sealer, the sealer protects the slab. The wax can be renewed every 4-6 months or as needed, the Sealer's Choice can be reapplied every 4-5 years.
So yes, film sealers are more bulletproof than penetrating sealers, but penetrating sealers perform better in a working kitchen that sees more duty than takeout food being heated in the microwave.
7) Forms. Screw then together then unscrew them to take them apart. Unscrewing allows you to be gentle, no prying or pounding required.
8) I line my forms with gloss formica. I might have mentioned that in another thread. The gloss formica gives an absolutely top-notch mirror like sheen to the top of the slabs. I usually end up having to take the gloss down a tad to a matte sheen. I buy beat up cracked or chipped sheets at the home centerfor a few bucks per sheet, I can reuse them for several slabs.
9) Another thought on reinforcement. I use 1/2" hardware cloth and rebar. Again, never had a cracked slab.
10) When placing a slab by myself, often times I'll keep the slab in the form. I have a rig that allows me to transport a slab on edge while still in the form. I screw dolly wheeels to the long edge of the form, one wheel fixed, the others swivel, and I'll maneuver the slab through the house on edge. Lean it against the counter, unscrew the form, the tip it up and slide it into place.
11) Plumbing penetrations. If the threaded nipple on the bottom of the faucet is not long enough to protrude through the slab, I make my plumbing stub outs to look like an inverted wedding cake. It results in a stepped recess so the nut can capture the tread on the faucet.
Nice post Waters. I've been doing these since '95. Welcome to the club!
Mongo
Great summation and tips. I have one to add that I was given by a great local concrete guy about white concrete for those who do CIP stuff. Buy stainless steel trowels for the finish, carbon steel trowels will leave black streaks in a white finish if you "burnish" the finish.
They can't get your Goat if you don't tell them where it is hidden.
It appears I lured another expert! THanks for your info! I have some ?'s and observations if you could possibly oblige:
1) If anyone will be doing a lot of these, consider using your own mix instead of a bagged mix. Reason? Replication. Can you make me a top like Martha's? Sure, because I know what any how much of each ingredient is on the mix. Bagged mixes can change over time, or be discontinued. Yeah, bagged mix is for dirtbags! ;-)
My mix works out to about a 7-sack mix equivalent. Never had a slab snap or crack. Can you describe your mix? Do you mix by volume or weight? What sort of agg. do you prefer? What type of cement? I've done cheng's sugg. mix by weight--peastone and type III with mixed results. What about water reducer? Which product and from where?
Keep a notebook of your work. Formulas, pigments used, cure time, sealer, etc. Always mix a bit more than you need and cast that leftover mix in a small form, say 6" square by 1" thick. Sounds silly, but it'll give you a reference for future color selection. I make myself 'pavers' with the leftovers. I've found that garbage can lids or the bottom of a plastic landscape plant container works well. You can buy yourself high-end molds in more intricate designs for pavers--suns, stars, whatnot.
2) Several references have been made to white portland. That's the ticket to getting a "clean color". Gray portland and regular sand will muddy the color of any pigment. That's not a bad thing, it's very earthy, you get some great results. But when you need to cast a canary yellow slab (yup, been there, done that) using white portland and white silica sand will allow thew yellow pigment to shine. My next counter is white portland and meant to turn out 'cream' colored. I have silica and wondered if I could use it. If I use silica, what grit? And if I use silica, and want to use broken glass too--do I need another coarse aggregate?
3) Ghosting. If vibrating after you set your rebar or pencil rod, the vibrating can casue the rod to settle within the mix. That's giving you the ghosting. Tie the rebar off to iteslf in a grid, then after placing your first layer of concrete, set the rebar and use wire ties to tie the rebar grid off to screws screwed into the form. Then place the remainder of your mix. No doubt--you have to be careful where the rebar ends up.
Vibrate, and the tied off rebar will not sink to the bottom of the form (towards the top of the slab) and ghost.
4) Vibrating. You can vibrate too much. Too much vibrating will cause the aggregate to settle, giving you an uneven composition throughout, and weakening the slab. That could be a contributing factor in your failed slabs. Understood. I was worried about this early on--but found after a few tops I had never vibrated enough. I htink the beginner's most common error is a mix that's too stiff, and not vibed enough. The cheng book and other info shows a mix that's so so stiff, and describes how this will be much stronger, less water volume, etc. I think we all err on the stiff side at first and that's no good if you can't vibrate it.
The rotary hammer works great. I also have a scavenged washing machine motor with an eccentric weight screwed to my casting table. Don't screw it to the form or you'll tear the form apart. Let the table shake the form. Only takes a minute or two and the results are consistent. You know it's working when the mud flows and the bubbles come up.
5) Why concrete? Good question. It's liquid stone. You can do things with concrete you can't do with natural stone. Some people get it, some don't. Different strokes.
6) Sealing. You can use a film sealer or a penetrating sealer. Film sealers are bulletproof in regards to stain prevention, but they make the countertop a bit less user-friendly. Meaning to a certain extent, you have to baby the countertop. Taking a hot pot off the cooktop or out of the oven and placing on a film-sealed top could cause the film to discolor or lift from the slab. Bad bad bad. I have a client that now wants a film sealer on her tops I did long ago. Do you have a lead on which product and where to get it? Make my own with thinned polyurethane? What? Help!
I may use a film sealer in some bathroom countertops where the top doesn't take the abuse that a kitchen countertop might.
Mostly I'll use a penetrating sealer, Sealer's Choice by Aquamix. Unlike some of the things mentioned in this thread, it's food-safe and is used in the restaurant industry. It's pricey, but a little goes a long way. Wipe on, let sit for 5 mihnutes, wipe off. Repeat two more times. Then buff with a coat of food-safe paste or some other type of food-safe wax. I've used this too. I usually have some of that around fromtile work. My tile supplier has it.
The wax protects the sealer, the sealer protects the slab. The wax can be renewed every 4-6 months or as needed, the Sealer's Choice can be reapplied every 4-5 years.
So yes, film sealers are more bulletproof than penetrating sealers, but penetrating sealers perform better in a working kitchen that sees more duty than takeout food being heated in the microwave. My client is sick of water rings, and citrus etching. Film sealer alleviate those?
7) Forms. Screw then together then unscrew them to take them apart. Unscrewing allows you to be gentle, no prying or pounding required.
8) I line my forms with gloss formica. I might have mentioned that in another thread. The gloss formica gives an absolutely top-notch mirror like sheen to the top of the slabs. I usually end up having to take the gloss down a tad to a matte sheen. I buy beat up cracked or chipped sheets at the home centerfor a few bucks per sheet, I can reuse them for several slabs.
9) Another thought on reinforcement. I use 1/2" hardware cloth and rebar. Again, never had a cracked slab. How thick are your slabs?
10) When placing a slab by myself, often times I'll keep the slab in the form. I have a rig that allows me to transport a slab on edge while still in the form. I screw dolly wheeels to the long edge of the form, one wheel fixed, the others swivel, and I'll maneuver the slab through the house on edge. Lean it against the counter, unscrew the form, the tip it up and slide it into place.
11) Plumbing penetrations. If the threaded nipple on the bottom of the faucet is not long enough to protrude through the slab, I make my plumbing stub outs to look like an inverted wedding cake. It results in a stepped recess so the nut can capture the tread on the faucet.
Nice post Waters. I've been doing these since '95. Welcome to the club! Thanks a lot Mongo. I remember a few of your posts. My first one went in our own house in '98 with the help of a distant cousin who knew what he was doing, but wasn't very forthcoming with the info. We mixed from scratch and when he threw in a cup of what I now know was reducer, I asked him what it was. He said, "Chemical..."
Eager for your answers!
Thanks again.
Pat"Research is what I'm doing when I don't know what I'm doing..."
I measure stone and sand by volume...but add pigment by weight based on a percentage of the weight of dry portland added to the mix. I use Type I/II portland cement, basic good ole 94 lb sacks of Quikrete, which is what the local yard carries. I don't have the need for the early strength afforded when using Type III, and I'm not in a big rush to get them out of the forms.Aggregate I use pea gravel. Aggregate give a bit of visual texture to the slab. If you want a dullish monochromatic slab, omit the stone and just use sand.I sometimes use a plasticizer. I get Pozzolith for free from a concrete block plant a few towns over. I used to use a material that came in single-use packets...I'd have to dig through my old records to see what it was.Leftovers. Yup, used to pour the extra into drywall buckets, about 4" thick. the next day I'd pop them out to get a nice round stepping stone. Used to leave them out on the curb, my neighbors loved them for their gardens.I've used stone with silica, it still gives a bit of visual texture to the slab without sullying the color.A film sealer will get rid of water rings and citrus/acid etching, but it does lend a "plasticky" look to the slab. Sort of like polyurethane on wood compared to an oil finish on wood.Look at Decosup and Prosoco. There has been a lot of improvement in the technology of film sealers over the past 5 years, Decosup sent me samples a while back, they have a basic penetrating sealer as well as a low-build film finish and a high-build film finish. the high build would be appropriate for a commercial installation like a bar or restaurant. The low-build should be fins for residential and doesn't look as filmy as the high-build sealers.Thickness? Thinnest is usually 1-1/4", typical is 1-3/4" to 2", if going thicker I'll do 1-3/4" to 2" for the field and use a dropped edge to make it appear thicker. Backsplashes about 3/4" to 1" or as required, whether they be integral or separate.You can also get some neat crazing effect by spritzing the form with water, then adding the mix. As the excess water is consumed in the hydration reaction, it can leave slight crazing cracks. Not structural, the surface cream is still strong as ever, but the crazing gives a very ethereal visual on the surface of the slab.Fun ones? I've done a few pastry slabs where I cast a cooling coil in the slab. I'll also cast markings into those to show various pastry round and square layout sizes.I'm tiring of integral sinks, though trough sinks are pretty neat.The fiber optic slabs I did a few years ago were phenomenal. I may do one for my pool patio...when I have some free time...which means never!Mongo
Hey!
Thanks for the reply great info. I'll comment/query below, if I may...
I measure stone and sand by volume...but add pigment by weight based on a percentage of the weight of dry portland added to the mix. I use Type I/II portland cement, basic good ole 94 lb sacks of Quikrete, which is what the local yard carries. I don't have the need for the early strength afforded when using Type III, and I'm not in a big rush to get them out of the forms. How long do you leave in the forms with type II? Perhaps some of us are getting cracks because 4 days or so is too early?
Aggregate I use pea gravel. Aggregate give a bit of visual texture to the slab. If you want a dullish monochromatic slab, omit the stone and just use sand. I use peastone too. You think there's anything to round vs. crushed rock for strength?
I sometimes use a plasticizer. I get Pozzolith for free from a concrete block plant a few towns over. I used to use a material that came in single-use packets...I'd have to dig through my old records to see what it was. I'll look into that, thanks!
Leftovers. Yup, used to pour the extra into drywall buckets, about 4" thick. the next day I'd pop them out to get a nice round stepping stone. Used to leave them out on the curb, my neighbors loved them for their gardens. I really wish that cousin (by marriage) that helped me with my first counter 10 years ago was still around. Concrete casting was his business and he had hundreds of paver molds and statuary castings....
I've used stone with silica, it still gives a bit of visual texture to the slab without sullying the color. I'll grind my next top and use silica--you think there's any problem with that? Wet grind, no dust to breath? Silica mud... I don't think it's a hazard, you?
A film sealer will get rid of water rings and citrus/acid etching, but it does lend a "plasticky" look to the slab. Sort of like polyurethane on wood compared to an oil finish on wood.
Look at Decosup and Prosoco. There has been a lot of improvement in the technology of film sealers over the past 5 years, Decosup sent me samples a while back, they have a basic penetrating sealer as well as a low-build film finish and a high-build film finish. the high build would be appropriate for a commercial installation like a bar or restaurant. The low-build should be fins for residential and doesn't look as filmy as the high-build sealers. Perfect--I think this client will prefer the 'plasticy' look to the rings. Thanks!
Thickness? Thinnest is usually 1-1/4", typical is 1-3/4" to 2", if going thicker I'll do 1-3/4" to 2" for the field and use a dropped edge to make it appear thicker. Backsplashes about 3/4" to 1" or as required, whether they be integral or separate. How the helll do you do a 3/4 backsplash that doesn't break?!
You can also get some neat crazing effect by spritzing the form with water, then adding the mix. As the excess water is consumed in the hydration reaction, it can leave slight crazing cracks. Not structural, the surface cream is still strong as ever, but the crazing gives a very ethereal visual on the surface of the slab.
Fun ones? I've done a few pastry slabs where I cast a cooling coil in the slab. I'll also cast markings into those to show various pastry round and square layout sizes.
I'm tiring of integral sinks, though trough sinks are pretty neat.
The fiber optic slabs I did a few years ago were phenomenal. I may do one for my pool patio...when I have some free time...which means never! I vaugely rememeber something on this? What? Whasssat?
Mongo Thanks a lot for taking the time to share your info. Much appreciated.
Pat"Research is what I'm doing when I don't know what I'm doing..."
Usually about 5-7 days in the form. I'm not in much of a rush, I mist it and keep it covered with plastic so the slab doesn't curl while it cures. I have pulled them out after 3-4 days.Crushed versus round slab strength difference? No idea on my end, brownbag would know.Wet grind = no problem. Except for the muddy mess! ;)3/4" backsplash? No stone, though I've used either just sand or stonedust as the "aggregate" in the mix. Hardware cloth for reinforcement, located towards the back instead of halfway. I did once have an integral backsplash crack on me. My fault, I horsed it a bit too much during the installation.Yeah, that was the couple who wanted a slab that "twinkled like the night sky". Funny couple. Great to work for, got huge leads off them afterwards. Mongo
Thanks for this thread, my wife and I are sitting on the couch reading the whole thing, sitting in front of the fireplace where we plan on a new hearth. Watched the Cheng video and read both books in the last couple of days. Learned as much or more here. Thanks! Getting out the rotary hammer to start tearing out the old hearth...
You're welcome. Hope to install that counter next week and I'll post that process.
"Research is what I'm doing when I don't know what I'm doing..."
I took mine out of the mold a week ago. It generally came out good, although it is more of a monkey-s**t brown than than the raw umber I had hoped for. I shoulda done some samples first.
There is slight ghosting from the 3 lengthwise pieces of rebar, but given the whole tone of the thing, it's not too bad.
I made an upturned back edge for butting the backsplash tile up to. After routing the melamine for the curve, I sealed it with clear packing tape. The packing tape left a glossy finish on the concrete - a very different finish than the melamine did. I will try to buff that out.
I vibrated it a lot, and so only got a few pinholes on the surface. Tomorrow I'm going to fill these with a slightly different color.
All in all, it came out pretty well.
Thanks again for the interesting thread.
Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.-Groucho Marx
Edited 3/7/2008 11:18 pm ET by musashi
Hey glad to hear it!
Color wise--the cream has the most intensity of color. If you want to get at it...grinding off that cream and getting into the sand just a little bit will change the color completely.
You could give it a go on a back edge for a test.
If you do grind, there will be some pinholes that expose themselves tho. and need to be filled.
Congrats! Sounds like it came out well.
Pat"Research is what I'm doing when I don't know what I'm doing..."
look on ebay... any mold that will work with plaster will work with concrete... most have a lip... i make small wood boxes to hold the mold... i have maybe 50 of these really cool cast concrete brackets i'll find a use for one day... i also have maybe 100 really cool trim pieces for tile borders... maybe 8" long and 2" wide... that i know i'll use...somewhere... i also have maybe 20 24"x24" x 1 3/4" thick "slabs" stepping stone... or i have used then to set small AC units on... the trick is to have the mold ready to use everytime you mix a batch ... just in case... with the molds i have (small to large) very little ever gets tossed... the small trim piece mold takes maybe 2cups of mix...
keep up the info..
p
Check these paver molds out:
http://www.designs-usa.com/Tile%20Pattern%20Paver%20Concrete%20Molds.htm
I found on ebay as you said, but sleuthed out the manuf. and they're a bit cheaper straight from them.
For my own place here we have grand plans for walks and paths in the landscaping. Having an armada of these molds ready to go would be a blast.
Really like that geometric pattern. I was thinking of casting my own, larger, pavers in my own molds in a similar 'golden rectangle' way.
Less effort-high reward with the plastic molds."Research is what I'm doing when I don't know what I'm doing..."
Hey, ? for you.
A client I did counters for a couple years ago now wants a more durable finish than the tile sealer/wax job I did for her.
Mongo steered me to a 2 part sealer meant for counters from Decosup. Looks like good stuff.
My ? is how would you remove the tile sealer and wax?
Decosup wants a non-polished, clean and dry surface to bond.
I'm paranoid the whole thing could flake off if I don't get the surface prepped right.
Any suggestions?"Research is what I'm doing when I don't know what I'm doing..."
FWIW I did one hearth that was sealed with a wax based sealer. Owner then wanted a different finish applied. I never could get all the wax out of the concrete. Later finish came up blotchy as a result. I tried ammonia, wax removers, floor strippers, heat , high flash thinners etc. and nothing I tried removed all the residual penetrated wax. Just a caution to be careful what you promise in terms of final look.
They can't get your Goat if you don't tell them where it is hidden.
exactly!"Research is what I'm doing when I don't know what I'm doing..."
maybe some kind of etching solution? If there is something that won't destroy the surface.
I do indeed plan to use basic etching solution to prepare the surface. It should create the 'tooth' required for the 2 part stuff I'm to use to bond.
We'll see."Research is what I'm doing when I don't know what I'm doing..."
I've steered clear of this topic... because all i've ever used was paste wax or bees wax... the reason for me is... i wax my molds with... paste wax... and i've always had the fear that if i tried to use a sealer some wax from the mold might still be on the surface...
sorry for the lack of help....
but... on my concrete floors i use... the same stuff you see on high polished supermarket floors... it's not for concrete... but it sure works for me
p
thanks anyway--we'll see how it goes.
Installing the counter in the thread tomorrow!"Research is what I'm doing when I don't know what I'm doing..."
Hey,
I checked out your leads on sealers and finishes. Decosup is it!
They have a 2 part water-based urethane that looks like the ticket. Thanks!
Question for you. They say that for adhesion, the surface should not be polished. Given this top has been polished, then sealed with a tile sealer, then waxed a billion times, what would you do to remove those coatings and get some 'tooth' to apply the new 2 part stuff?
Etch?
Thanks,
Pat"Research is what I'm doing when I don't know what I'm doing..."
Best advice I can offer is to strip the wax then take the polished sheen down with a lower grit disc.
I'd be careful using an acid to etch.
First talk to the customer. See what they want. Grinding the surface with a lower grit disc can give a different look than using an acid to etch the surface.
Etching may be less uniform as well.
Glad the Decosup worked out for you.
What would you use to strip the wax?
Thanks,
Pat"Research is what I'm doing when I don't know what I'm doing..."
Wouldn't you know it...great chance for new tools and I already everything you used. Thanks for this info. I have to do my own counters this summer and I seriously needed this info.
john
You're welcome.
Tomorrow I'll post the install process."Research is what I'm doing when I don't know what I'm doing..."
Any commercial stripper should work fine (just have some 1$ bills handy) or you could make a homemade solution, something along the lines of vinegar and ammonia in water.
A scrubby pad would do the trick.
Mongo
See dovetail.
I would think this is a perfect place for this kind of work--and plan to do it myself.
I would also guess that durability had a lot to do with your area also. If you have really harsh winters, nasty freezes, and hot humid summers vs. mild weather year round.
If the counter is sealed well and waxed frequently I'd guess it would be well protected.
That and if it cracks outside--so what? Character."Research is what I'm doing when I don't know what I'm doing..."
Is there some reason why a concrete vibrator can't be used?
Yeah: I have a rotary hammer on hand... and no money in the budget for tool rentals!
Outside of a dog, a book is a man's best friend. Inside of a dog, it's too dark to read.-Groucho Marx
Edited 2/19/2008 8:36 pm ET by musashi
FYI
During my kitchen counter build I used a 7" variable speed grinder/polisher with a sanding pad mounted off center and attached it to the table using the accessory handle mounting hole. I started it up and used the trigger lock to set it at a good speed and let it vibrate the whole table. Worked rather well. <!----><!----><!---->
This was a cheap Harbor Freight model I didn’t mind destroying. It survived just fine and the bonus is that it worked great for the grinding and polishing later on…<!----><!---->
I have some concrete counters I did in my kitchen about 7 years ago. Dyed black and I never ground them. After all this time, they're showing plenty of staining from citrus and such.
I was sort of thinking, is it possible to grind them down now using the mentioned technique with the angle grinder and diamond pad? If successful, it'd be like a whole new countertop. The problem is that I can't move them, so I'd have to grind up in the house. How would I handle cooling and/or dust control?
Or are they just too hard by now to consider messing with?
Problem with giving it a try is that once I've started, I can't stop until its done and done right...
Your "How To" is excellent. A couple of questions, working by your self how did you flip the mold. You must be pretty burley. <G>
I think if I was going to make a form table how about making it on a flat anchored platform with leaf springs on one side of the 2x6 frame and using a electric motor with variable speed and a eccentric cam to shake the whole table?.
What about embedding decorative tile in the bottom (top face of the counter) on the mold. Seems like a neat idea. Another Idea I saw somewhere someone tapered the one side to make a drain area with copper rods on the surface. Really looked nice.
Great series of photos and how to do's. Thanks for sharing.
Jim
Your "How To" is excellent. A couple of questions, working by your self how did you flip the mold. You must be pretty burley. <G>
The flip is pretty manageable with a smaller counter but more hands are certainly recc!
I think if I was going to make a form table how about making it on a flat anchored platform with leaf springs on one side of the 2x6 frame and using a electric motor with variable speed and a eccentric cam to shake the whole table?.
I actually don't know that that would work. I think the springs might absorb more of the vibration than transmit it to the table and the piece. To really vibrate and settle the contcrete it seems something 'rattling' or 'striking' the table or the form is what does it. Cheng's got it down with clamping a stinger (a real concrete vibrator) right to his table--which appears to be made of TJI's and big lumber--and rattling the hell out of the whole table. I dunno. Good thought though.
What about embedding decorative tile in the bottom (top face of the counter) on the mold. Seems like a neat idea. Another Idea I saw somewhere someone tapered the one side to make a drain area with copper rods on the surface. Really looked nice.
Sure, you can put whatever you like in the bottom of the mold/face of the counter. That's what's so cool about cc counters is the ability to do something really different--even surprising. Sticking a bigger piece of granite--even with rough broken edges into the face makes a great place to bake, for instance.
Great series of photos and how to do's. Thanks for sharing.
Thanks! My pleasure."Research is what I'm doing when I don't know what I'm doing..."
I haven't done it... but it's a thought i've played with... granite inserts... large 12x18" ect... weird natural shapes... drops, broken parts and left overs from the granite shop... i see all this stuff lean'n up against the outside of his building... so i know he can't value em too much...
thought both cast in place and in molds... cast in place set em like tile.... put em where they would work for baking or for hot pots ect... might look tacky or might be interesting...
p
Great tutorial, and very nice top.My son and his partner are trying to start up a concrete business. Partner's been to a couple of Cheng's sessions. They're tooling up. Got a couple of bolt on vibrators, a tow behind mixer...and the 1200 buck table saw<G>They just poured two nice column caps for a house I'm building... the "good" sides didn't come out so good, so they flipped them, and ground them down to the aggregate... with a big honkin' Milwaukee 7", of course LOLCame out great, all kinds of neat stuff in the aggregate... pyrites, quartz, and various other weird things.I'm going to get them working on vanity with seashells I've always said I could do something with, ha.Keep up the lessons, I'm forwarding all this to them... whatya bet I see a rotary hammer in their shop next? Winterlude, Winterlude, my little daisy,
Winterlude by the telephone wire,
Winterlude, it's makin' me lazy,
Come on, sit by the logs in the fire.
The moonlight reflects from the window
Where the snowflakes, they cover the sand.
Come out tonight, ev'rything will be tight,
Winterlude, this dude thinks you're grand.
Yeah you can grind in the house. With the 4" pads I and others use, you don't need that much water--but it does really help to clear the 'mud.'
I use a garden hose outside but I've heard it rec. that you can punch a few small holes in a 5 gallon bucket and let them piddle out in front of you.
The cheng book shows refinishing a counter in a house. He's taped and tarped off everything but the critical feature is that at the counter itself you form a masking tape lip that will dam the water. Also, it helps to have an undermount sink to run all the wastewater into--or you make some type of a 'chute' to let the water off the side of the counter into another bucket or whatnot...
I think it's possible.
You might even be able to do it with a dry setup, if you had a really good dust collection setup. I know there are ways."Research is what I'm doing when I don't know what I'm doing..."
Smart..
I can just see that too--start it up, let it go and stand back!"Research is what I'm doing when I don't know what I'm doing..."
Congrats!
"Time for a malt beverage. "
A necessary part of the process.
"Research is what I'm doing when I don't know what I'm doing..."
"By the way, the outlines of the rebar are already showing in the bleed water. Maybe different patterns of water escaping affects ghosting? Just an idea."
Without a doubt.
Simply, I think the metal's a different consistency than the mix--therefore different curing, hydrating, ghosting..."Research is what I'm doing when I don't know what I'm doing..."
This is fascinating, do you get the dye at HD as well? I am also wondering what pencil rod is.Can't wait to see more installments.
HD has some dry pigments--but they're pretty basic--black, terra cotta... Find a masons supply in your area and they'll carry more. Or better yet:
http://www.buddyrhodes.com/signature_colors.html
http://www.concreteexchange.com/catalog/
http://stores.ebay.com/Direct-Colors-Inc_W0QQ_trksidZp1638.m118.l1247
There's A LOT of decorative concrete business out there. I haven't ordered anything from these guys before.. still pretty 'dirtbag' in my world of countertops. I do have one coming up where I'll use white portland, my own mix and some broken brown beer bottles for aggregate. That over a copper undermount vanity sink.
We'll see how that goes.
Pencil rod is a thin metal rod in 20' lengths for forming foundation walls--found at the mason's supply.
Cheers,
Pat"Research is what I'm doing when I don't know what I'm doing..."
This is very timely. I'm considering Concrete CTs for my kitchen redo and have just started my research.Thanks - keep it coming.
http://grantlogan.net/
I refuse to accept that there are limitations to what we can accomplish. Pete (I am so in love with myself) Draganic
looking forward to the next installment ! The "ghosting" that happened from the pencil rod -- does it go away as the concrete continues to cure ? ... and what exactly is happening to cause the ghosting in the first place?
Ghosting occurs when metal reinforcement is close to the surface of the counter--say within an inch or so. On a 'thin' counter, this one is 1 3/4", it's pretty hard to avoid.
If you are going to grind and polish the surface of the counter, then it doesn't show at all. On this counter, as I'll soon post, I start with a 50grit diamond pad that takes the cream right off exposing the sand, mostly, and some aggregate. You can get more aggressive with the 50 and expose more of the larger aggregate if you like.
It must be caused in some respect by temperature--you've got this cold metal in the mix--and that in turn affects how the mix hydrates and cures, and looks.
You can really see it in this photo.
"Research is what I'm doing when I don't know what I'm doing..."
Super thread! - been wanting to try the concrete counter thing.
That's my favorite thing about Breaktime - how-to threads with lots of pictures.
Forrest - SecretSanta still at work resolving technical issues
Honored to have the approval of the greatest how-to poster of BT all TIME!
Mr. Bridge.
Cheers,
Pat"Research is what I'm doing when I don't know what I'm doing..."
what's your issue with the secret santa thing?
I'm really late - I'm his secret Santa, and technical issues have delayed delivery. It will happen!
Forrest
Better...
Don't make me come down there.
:)
Ba$stard hasn't sent me my gift yet!
But judging from his bridge... it'll be worth the wait.
How he's going to get MY bridge out to Oregon, I dunno..."Research is what I'm doing when I don't know what I'm doing..."
Great thread!
When doing a cc top, what choices do you have for a backsplash? I'm guessing that an integral back splash (like a post formed laminate top) would seriously complicate things.
Jon Blakemore
RappahannockINC.com Fredericksburg, VA
I've seen tries at CC backsplashes and they're so fragile--they all break.
One neat detail I've done is to use a roundover bit on the 'back' edge of your mold face. This will create an upturned 'lip' at that back edge for the CC to fall into. Then you apply a 3/8" (or otherwise 'tile' thickness) band around the perimeter to that, and screw your sides on to it--thru it--into the mold.
The finished surface then as an upturned back lip that you can tile down to for your backsplashes. No water ever behind the counter."Research is what I'm doing when I don't know what I'm doing..."
"I've seen tries at CC backsplashes and they're so fragile--they all break.One neat detail I've done is to use a roundover bit on the 'back' edge of your mold face. This will create an upturned 'lip' at that back edge for the CC to fall into. Then you apply a 3/8" (or otherwise 'tile' thickness) band around the perimeter to that, and screw your sides on to it--thru it--into the mold. The finished surface then as an upturned back lip that you can tile down to for your backsplashes. No water ever behind the counter."I did a set of back splashes this fall. For the most part they turned out fairly well. 1 1/2" at the base where it met the countertop tapering to 1" at the top of the back splash. They were
about 4 1/2" inches high and I had sections ranging in length from 72" to 24". I used pencil rod in all of them. I did have a series of small cracks (3) in the 72" piece but I decided to try and salvage it. As I was installing I couldn't even find them anymore.
That's cool. I hadn't thought of tapering."Research is what I'm doing when I don't know what I'm doing..."
Thanks for take'n the time to post & share...
since i'm pretty sure my time has no value and... i'm still try'n to use up the 80,000lbs of white portland i got 3 years ago... concrete is cheap for me...
I have never ground a counter surface "yet" but I do plan on it... I've purchased bags full of garnet, jade and who knows what else... cast offs from people that make jewlery with the idea of use'n em...
I pretty sure it was you (or some breaktimer) that gave me the roto hammer vibrator idea... and it so far is one of the best vibrators i've used for casting... many thanks for that one...
what i do to keep from grinding... my steps are just about same as yours... but i cast on sheet lexan sign face material... i get it free from a sign shop (sign installer) many sheets i get are all but new where they changed logos or store names... most of the lettering these days just peels off... but even if it didn't you still have one clean side...
i use this same material cut in strips the thickness of the countertop for the sides... very easy to free form curve and bends with it... a little heat and you can bend anything these curved formed edges go into a standard form like yours... but i cut blue board foam to back up the thin lexan curved sections... very easy to strip the forms... and i can reuse the bent shapes 5-6x before they start to crack... i'm not sure why they crack at the bends after use...
i wax all of this with johnsons floor paste wax..(no buffing just put the wax on) car wax works also...
casting on top of this plastic gets you an almost glass smooth surface with all but zero voids... i have only had to go back and grout/fill one top out of 30 or 40...
I too find that i needed to use a wetter mix than any of the books said...
i have cast about 12 bath vanities with the sink cast into the top... ie; I use a small stainless sink and thru the drainhole bolt it to the form (long all thread) and just cast to it... they have turned out very well and skips a few steps.. makes them real flush mount sinks... for the faucet hole or holes (i try to use faucets that require one hole) i too use the slit pvc with tape but i use a washer on top and a deck screw and just screw it into place... i do finish the bottoms of my tops... just cause i like to finish concrete... and i use an edge tool around the form to ease the bottom edge...
i have looked at the colored rock for fish tanks and though it might have some use...
i have yet to do a large "pour in place" but i do have plans to... and have given it some thought...
again many thanks for take'n the time to share and to show that it really isn't rocket science... and for those who want something a bit more special than formica for about the same material cost... it can be done
last note... on ebay you can pick up some really cool molds for trim, or brackets, ect... that are fun to cast up with left over mix... even if it's just a stepping stone still more fun than toss'n the left over mix
p
Aha--I've attracted a true expert.
You've done more than I have.
Yes it was me the Rotary Hammer. That works.
Where are you that you have so much counter business--what is your regular business--how many are you--and do you have any photos of your stainless sinks cast right in?
That' sounds cool--and low effort--high reward.
Thx,
pat"Research is what I'm doing when I don't know what I'm doing..."
Hi, Ponytl, you posted this some time back in the concrete countertop thread"I use a small stainless sink and thru the drainhole bolt it to the form (long all thread) and just cast to it... they have turned out very well and skips a few steps.. makes them real flush mount sinks..."Do you route a recess into the mold for the sink lip to sit in? Or screw a ring to the mold, so the sink is captured in the top?
i place the sink (which is a standard surface mount sink) face down in the mold... hold it down with all thread and a nut/washer to the mold so that it's held tight where i want it... i then fill the small gap around the edge (of the sink where it meets the mold) with paste wax... i use the normal pvc deal for the faucet hole (again held down with a washer and screwed to the mold) i leave the pvc in the cast piece vs slit'n & remove'n it... the concrete captures the sink... ie... it'll never come out... if you were to route a recess in the mold for the sink... then it wouldn't be flush when you pulled it from the mold... it'd be just like you left a hole and set the sink in it... i've done about 20 so far like this... and they turned out well... again i cast on lexan (old flat sign faces) and i get a super smooth finish as a result
p
Ok,
Here's the last post before I'll borrow another set of hands (and stronger back!) and set this counter. Another reason it doesn't make business sense for me to be doing these things--I work alone and can't move the stupid things around!
Now that you've waited your 4 days or so, flipped your piece, prised it out of the mold and seen what you've got, it's time to fix it up and make it ready for the cabinets. I borrow that set of hands here to help me move the whole piece outside on another set of leveled horses. I pick up the whole base that I intially made, with the piece on it and move it to the other horses so I won't break it.
By the way--this one's small enough I didn't have to split it in two at the sink. A larger counter makes this impossible--it'll break around the sink if it's one piece.
I grind and polish most of my tops which exposes whatever aggregate, sand and whatnot are in the mix. You don't have to do this, of course, but the difference is a flat, monotone color or a variegated, colorful piece that can be changed along the way even.
3 or 4 days is still 'green' enough that you can grind away quite a bit of material without much effort. After 7-10 days the piece is really too hard to do anything but polish.
To grind and polish you do need a couple specific tools--but not the 400$ + water fed super setup that you read about in the book... #1 get a variable speed angle grinder, and #2 a set of diamond impregnated polishing pads off ebay. IYou need a grinder that's slow--3,000 rpm vs. the 12,000 rpm that a regular one goes off at. I bought a makita variable speed grinder for about 175$ but I'm sure you could do better than that. Then, diamond pads and their backer for the grinder cost less than 50$ on ebay!
I got a set of 7 or so pads that go 50, 150, 300, 500, 1000, 2000, 3000. I start with 50, end with 500 and never use the top three... Not like somebody needs to shave looking into the counter in the morning...
When the piece comes out of the mold, it's likely to be pretty darn glassy, with no pits. This is because the 'cream' in the concrete settles against the surface of the mold. The cream also holds most of the colorant, so when you remove it, with the 50, you'll dull down the color A LOT. This will also expose a few pits that weren't there. These will need to be filled.
Cheng outlines using cement, water reducer and pigment to make a slurry to fill these with, then grind again. Buddy Rhodes even uses this to his design advantage to make things that resemble terrazzo--stiff mix, lots of voids, then fill with slurry of different color and grind again.
I use unsanded tile grout. Color it with your pigment of choice. On this counter my mix was indeed a little stiff so there were some pits. Mostly just air bubbles. So I got a wild hair and used red pig. to fill and you can see the results. I schmooey it all over the piece and let it cure, then grind again. I think it turned out nice.
Now that it's polished up to about 500grit on the pads, it's nice and shiny and I've removed any visible scarring from the grittier pads. Now I can seal it, wax it and it's ready to set on the cabinets.
I seal with regular old grout and tile sealer. The photo shows the garden variety Tilelabs stuff available anywhere. I've gotten a notch better stuff from tile supply store... After two or three doses of that stuff, wait til dry and rub in paste wax--I get stuff from woodcraft that I think is just beeswax cut with mineral spirits. I think anything would work. This will give you a semi-porous layer on the cc that wil prevent any real nasty staining, but it is porous and things will get thru it. Some colors show A LOT more than others--blues and greens like this, seems to hide a lot of water stains and whatnot. Black shows... Funny though, a ring from a glass will be really intense like "OH ####!" and then 3 days later it's totally gone. Citrus will etch cc just like granite. Look out.
Anybody (ponytl?) who knows about any better sealing finish--epoxy?--I need to figure that out soon for another job.
I got a little 4" lambswool bonnet for the grinder and that works great.
Might be a bit, but I'll photo and post the install too. I have another job going right now.
Thanks all.
"Research is what I'm doing when I don't know what I'm doing..."
Oh yeah--and the yellow electrical thingy is a GFCI pigtail what to keep you from electrocuting yourself as you stand in the muddy backyard puddle grinding away at your concrete countertop... This is a necessesity if you don't have a GFI protected outlet to plug into."Research is what I'm doing when I don't know what I'm doing..."
Cool thread.
How do you attach the sink?
Ihope to photo the install and show that, but basically:
Put the counter on the 3/4" ply substrate. Trace the opening you made for the sink.
Cut out the hole, a little bigger.. Whatever the lip on your undermount sink.
Lay the undermount sink over your hole and trace again.
Rout out for the lip (sometimes this isn't nec. as the lip is thin enough) of the sink and stick it in the hole.
Set counter--with lots of 100% silicone.
If you made a template for your sink knockout by actually tracing the inside of the bowl(s) then your counter will likely overhang the sink a bit more than normal. Ithink this helps."Research is what I'm doing when I don't know what I'm doing..."
Oy yeah,
There is some harware available for undermounting sinks in a much larger hole--a frame that goes across the larger opening.
I saw the granite guys do this on a kitchen remodel I did."Research is what I'm doing when I don't know what I'm doing..."
"3 or 4 days is still 'green' enough that you can grind away quite a bit of material without much effort. After 7-10 days the piece is really too hard to do anything but polish."Thanks for your detailed description of the process. It's nice to have someone to exchange notes with. I usually use a "High-Early" mix using type III cement. I never grind sooner than seven days and usually wait between 7 and 10. Never had a problem with slab being too hard to grind and polish. The last slap I did I really ground to expose a lot of aggregate. It looks like terrazzo. I started with 50 grit and went up to 3000 grit. The grinding went fairly easy although it was quite tedious exposing so much aggregate.
I haven't looked much.. but it seems to me the 4" diamond pads are 'high effort - low reward' when it comes to really gettin' at it.
I know there are cup wheels and whatnot that are larger/faster but wouldn't a 7" pad be perfect?
Up to 3,000 ey! I tried up to 1000 once. Pretty glassy. Where do you get your diamond pads?
Type III - I use that too when I mix from scratch. NExt one I'm doing is going to be white portland, with broken glass in it. SOmeone here had some great photos and a story about using heineken bottles.
"Research is what I'm doing when I don't know what I'm doing..."
Hey, thanks for taking the time to make this awesome thread!
The counters look great!
Regards,
Steve
"Preach the Gospel at all times; if necessary, use words." - St. Francis of Assisi
Here is the final installment on a dirtbag's backyard concrete counter production!
Last installment had the counter moved outside, ground and polished with wet diamond pads. Some pits were filled in with pigmented tile grout. Then sealed with a polymer tile sealer, paste waxed and buffed shiny.
Then it was left out in the rain for several weeks while I did real work...
So today finds us placing the counter on my clients nice maple utility room base cabinet.
You should be sure that the cabinet is up to the task. Its upright panels should make it to the floor and there should be a ledger all the way across the back, against the wall, with a good #10 screw in every stud.
Then 3/4" cdx ply nailed or screwed on top of that. Make sure the surface is clean and nothing is proud.
Next locate where the sink cutout will be. The 'truest' way of doing this is to place the counter on the cabinet, trace the sink opening, then pull it off and cut away. I made a paper template from rosin paper and used that as I didn't have any extra muscle when I prepared the cabinet for the counter.
THis undermount sink has a very thin lip to it and would probably be fine between the counter and substrate, but I routed a recess for it anyway. When you cut your hole and rout in for the sink's lip, be sure to give yourself some 'slop' so you can shove the sink one way or another once the counter is placed over it. I watched a granite counter install a while back and they cut wayyyyy out much larger than the sink and used a frame gizmo that alowed you to align the sink easily and snug it up to the underside of the counter well after the top was placed. Forgot the name of that thing.
Now you're going to caulk the he[[ out of the rim of the sink to be sure no moisture ever makes it between the sink and counter. A few lines of caulk work to bed the top on the rest of the cabinet as well. If you have a thinner counter, or a questionble substrate to set it on, one thing I've done is to knotch-trowel on some thinset mortar and bed it in that. The flexible type. BUT, if you ever want to get the counter OFF again, wax the underside too to prevent a bond. The weight of the counter is well enough to keep it placed.
"Research is what I'm doing when I don't know what I'm doing..."
FWIW here are some brackets that allow you to install a sink from under the top.http://www.vanceind.com/index.asp?PageAction=VIEWCATS&Category=16I think that there are other brands out there..
.
A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Those are they!
Thanks BIll."Research is what I'm doing when I don't know what I'm doing..."
Another Dirtbag Backyard Counter:
This is a shallow vanity top with undermounted hammered copper sink. One hole faucet will go off to the side, and a 'soap indent' off to the user's right.
It's white portland cement, with 3/8 round rock, 1/2 silica sand and 1/2 natural washed sand.
I washed the rocks really well in the mixer too, to make everything clean and shiny.
As the photos go how to make the sink knockout again:
This sink came with no blank template, and I don't like the templates that come with a sink anyway--they usually leave too much of the sink exposed--so I traced myself one.
The vanity sink has a 1.5" hole unlike a kitchen or bar sink you can reach thru, so I stick a sharp pencil into the end of a dowel and use it to trace the sink onto 1/4" hardboard for a template.
Now because the sink is handmade and irregular, I adjusted the template by eye and marked the sink and template in one corner so when I put the sink in, it'll mate up.
I've traced the blank I made onto the material I'm making the sink knockout with (1 layer of 1" melamine, and 1 layer of 3/4" melamine for a 1 3/4" counter thickness) and I cut outside the line with a jigsaw.
Now screw the template to the material and flush cut around it with the router.
Now screw the two pieces together, predrill or they'll not suck up together well. And, screw them to the bottom of the form."Research is what I'm doing when I don't know what I'm doing..."
The photo of the form shows aluminum divisions to separate the counter in two at the sink. THis is necessary with bigger counters where the sink area is really fragile. I bagged that idea at the last minute here and went for it.
Seal the mold with silicone caulk and run your finger over it all. Creates a nice little radius.
Here is the counter out of the mold and moved outside for grinding and polishing.
The sinkknockout.
Ground not as aggressively as the previous counter in the thread--starting at 150 instead of 50 which really takes off the cream and sand--gets you into the aggregate. THis exposes a nice mix of cream and sands. Don't know if you can see it in the photos.
Here is today's assistant. "I am not stupid! I'm HAPPY.""Research is what I'm doing when I don't know what I'm doing..."
Very cool. This thread is great. I am thinking about attempting my first concrete counter for an existing kitchen island. I would like to make it with a thickened edge, so I can just drop it on top of the existing laminate top. Have you ever done this?
Hi Jesse,
I did one in place, that is, forming it on top of the cabinets, dumping the concrete right in the form, and finishing the top of the counter with steel trowel, that did have a dropped edge. But only enough to fall below the 3/4 substrate.
To cast one in a mold, as such, you'd have to blank out the whole center of your mold--making a giant inverted bowl.
Might be tough. High effort, low reward.
I'd probably rip off the laminate counter and start fresh, unless you wanted that extra height? Then I'd just trim the old counter showing below your new cc counter with something--wood, metal, tile..."Research is what I'm doing when I don't know what I'm doing..."
Here's the last one, white portland, silica sand, ground and polished, hammered copper undermount sink... Completed and in place.
"Research is what I'm doing when I don't know what I'm doing..."
Beautiful job!
Thank you.
two more coming:
Small vanity counter: White portland/broken brown beer bottles. Same sink.
Little bigger vanity counter: White portland/silica. Same sink. Set on Antique Oak chest."Research is what I'm doing when I don't know what I'm doing..."
Still working on the brown glass? :-)
Oh yes. 1 a night.
Ironically, that's for a client I keep putting off. She's told me 'anytime' and 'no rush' so I keep selling the sink I got her to somebody else, or putting it off.
If she told me 'next week' then it would be next week, but 'anytime' indefinitely coming I guess.
I ordered her another sink today. No excuses when it gets here.
"Research is what I'm doing when I don't know what I'm doing..."
Did you get the next sink yet? Looking forward to the beer bottles...
Hey,
Yes, I've got two more sinks and been drinking a lot!
Now I have to get moving on the two tops--one's for the current bathroom I'm working on and will be set on an antique chest as a vanity. That'll be whiteportland and silica sand as the last one was.
The other is the beer bottle counter with white portland and brown 'Lagunitas' bottles!
Perhaps later this week!
thanks for checking in!
Pat
new pics?John
J.R. Lazaro Builders, Inc.
Indianapolis, In.
Will you guys give me a minute!!
;-)
Yesterday and today I did 2 more tops using Ponytl's 'bolt the sink in' method as he just described.
I took photos, but thus far they're of the the 'dull' part building molds, integrating the sinks, crushing glass...
In a week they'll come out of the molds and I'll grind and polish. THAT's the fun part!
I'll download the photos and describe what I did yest/today Asap.
Thanks to Ponytl for the method!
The long-awaited beer bottle counter!
I have two counters I've got in molds now. Both are wht portland cement like the last one, with 1/2 silica and 1/2 washed regular sand (quikcrete's bagged stuff) and 3/8 round rock. One of the two has crushed brown beer bottles subbed in for half the rock in the recipe.
I've started using the Mongo recipe described earlier which is broken down by volume. Here is my little spreadsheet calculator. Measure the form's volume in cu ft and insert that number up above.
I too made myself a 1 cu fut BOX out of plywood and graduated it inside so I can see just how much material I've got. Then I dumped 1/4's into buckets and drew lines inside them for measuring. This method has turned out much better than mixing by weight as described in Cheng's book.
Here are pictures of one of the two molds, done as previously posted only rather than undermounting the sink, I'm bolting it face-down in the form as Ponytl does. This surface mounts the sink in the counter for good! I 'painted' one sink with urethane as a form release in case I do want to remove it for the grinding and polishing step. I forgot to do that one on the other so it's in there for good!
Pony says he uses paste wax to seal the sink to the mold. I went with modeling clay. Put a bead of it around the rim and bolt that sucker down thru the form. Then trim off what splooges out and you've got a perfect seal.
Pictures show a "ponykit" with thread rod, washers and some clay and the form ready to go with pencil rod reinforcement. The knockout for the faucet is the same pvc, slotted, wrapped in duct tape and stuck into a hole drilled all the way thru the form. Easy to get out this way.
Here's how I did the broken glass aggregate, to be exposed later in the counter surface by grinding and polishing with wet diamond pads in the grinder.
First I saved up a bunch o' beer bottles. Somewhere back in the archives there's a pretty funny thread somebody wrote on a counter they made for aclient with green crushed glass... had to go thru a case or 2 of Heine for that one.
Indeed it takes quite a few bottles. I first soaked mine in TSP subst. for a bit to clean them and remove the labels and glue.
Then, nonplussed to the notion of bashing them with a hammer, or throwing them against a wall somewhere I set them all in the mixer with this here rock. Louder than hell, but it worked. 2 more rocks sped the process. Tumbling the glass for some time I think was a good idea too--knocked down the sharps and I think rough glass will have much better bond in the mix. I strapped plastic over the mouth of the mixer to contain the glass explosion. I was also concerned none of the pieces where to overly large. The glass ended up being no larger than 1" or so and I think it could have been smaller. What's that rule about size of agg. and thickness of slab?
Making my own crushed glass aggregate was pretty fun (burp..#o*) but created issues I hadn't considered. A big qty of busted up glass is hard to deal with--don't want to just dump out the waste on the lawn!
Here are the ingredients ready to bake the cake.
The sand(s) are clean, but I wash the rock really well as it's dirty and would really muddy up the counter color (might be good color but darker).
I put the rock in the mixer and let it wash them. Assistant loves this part... Two or three rinses and it runs clean. I've heard this helps the bond in the mix too...
Then I ran the glass and the rock for a while to further tumble the glass.
In pouring, when the sink is sticking up out of the mold like this, you've got another minor challenge. You can't just screed right across the mold. So your screed'er should be longer than the mold everyway and you can screed around the sink reasonably well. The larger glass agg. doesn't screed out flat like 3/8" rock either.
In a week or so, I'll flip these two and grind and polish them--see if we've got heavy junk, or masterpieces!
So The beer bottle counter is in process and another white portland non-bottle counter is placed.
Here's both, oustide ready to grind with 4" wet diamond pads @ 3,000rpm or so with the makita variable speed grinder.
50grit gets into the glass pretty quickly.
I discovered right away that broken bottles might not be the best aggregate as they are convex and anything in the surface has to be ground far down to flatten out. The glass aggregates you can buy are probably more worth it this way, but it sure was fun accumulating enough bottles, and then busting them all to pieces! (see the few previous posts)
Here is the whole counter exposed. Now I've got to work down the grits to really smooth it out.
Now that the glass in the counter is well-exposed, I'm going to use regular old unsanded tile grout as a slurry to fill voids and pits. Works better than making a cement slurry and you can color match pretty easily.
Here is the non glass counter ground to 500 grit. It's pretty smooth. I could go further and make it glassy but no point really...
Here it is in place in its new bath home on an antique oak chest from the antique store. I left a few cards and Mike Guertin's article on converting a bureau to a vanity with the guys at the antique store and I already have calls for conversions with CC counters.
forgot the photos!
Edited 5/29/2008 11:58 pm by Waters
Photos from above.
Very nice, keep 'em coming. Where do you get the white Portland? If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Thx,
Masonry supply store. West coast has "mason's supply."
Glass counter completed and installed!
Been a while with other work but here is the result of the white portland/silica sand/3/8 round rock and broken beer bottle counter top!
I may have mentioned a couple issues with breaking up your own glass (see previous posts on method) and using it as aggregate in a counter--fun prospect, but several dozen broken bottles are #1 hard to break up small enough in the first place, #2 sharp and dangerous, and #3 have lots of concave/convex surfaces that don't 'sit' well in the flat surface of the counter without lots and lots of fill and grinding. Lots of polishing too--finer than you normally would grind a simple concrete counter to get the glass back to a shiny/clear state.
Came out well, but more work than I'd anticipated. I would look into buying glass aggregate in the future. I know theres quite a few outfits on the net that carry it.
Here is the counter ground (a lot) and polished.
And here it is in place. This one fit the wall perfectly by the template and the client opted out of a backsplash.
Ya done good there, sunshine!
Yeah, that there is the product of your concrete recipe by volume, not weight, and 1 cu foot 'box' you posted making, which I did and was surprised to see that 1 5-gal bucket is only about 1/2 a cubic foot...
and Ponytl's bolt-the-sink-right-to-the-form surface mounting technique.
Thanks!
I've got another to go template for--with another dresser vanity the client just bought from the antique store--which gave her my business card.
Yeah, but if you buy the glass, it's not the same as emptying them yourself.John
J.R. Lazaro Builders, Inc.
Indianapolis, In.
Without a doubt.
There was another post on cc top with glass, don't recall whom, but he and his crew had to empty 2 cases of heine for the green glass in their's!
P
i like it
View Image
one step closer to trying one of these... keep the inspirations commingMike Smith Rhode Island : Design / Build / Repair / Restore
Very nicely done. We are having a devil of a time finding white portland... the bottles are a piece of cake<G> Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
I don't know where you'd find it in NC.
I get it at "mason's supply" which is a concrete supply house (if you couldn't figure that out by the name...)
Try calling the ready mix guys and ask where to find it.
Good luck,
Pat
I've got two more in line. One simple grey one... blah...
and another at the beach remodel I'm working on where they have collected a zillion agates. They want them in the surface, ground and polished.
I think that'll be awesome.
Isn't it amazing?When I think back at the number of cctops I've done, it's sort of shocking.When I think back on what I got paid to make those tops, it's even more shocking!
Started another countertop tonight.
A simple grey vanity top with the same hammered copper sink embedded in it. Will go on another antique chest turned vanity.
Jubelale "a festive winter ale"
Looks nice, but I think you're gonna need way more duct tape than what you have there. And the Jubelale won't be much use at all. May as well just drink that.
(Disclaimer: I'm kidding!) =]See my work at TedsCarpentry.comBuy Cheap Tools! BuildersTools.net
Duct tape--It's to make that knockout slide out easy later. I've used it on edges of sink knockouts too, that will be exposed in the counter. Has a nice texture in the finished product.
I heard the other day that 'Silence is Golden..... duct tape is Silver."
Which at first I thought was really funny, as I have a 4 year old that sounds like several children sometimes. But then after I thought about it, not quite sure... That's a fine line there.
greatest thread ever. been researching online for weeks, got all the books and this thread is mo' better. i have a question. i lucked up and got a big job (4 houses all with large kitchen ct and island with a bar attached to island). i've wanted to do this for years, anyway i convinced the builder i knew what i was doing but have only done one so so job. any advice on transporting?whats your opinion of the diamond mesh vs rigid 4" vs rebar? it looks like you're a rebar man. i've read the whole thread and may have missed it but could you explain the cubic ft box you were talking about earlier? the whats, whys, how'salso if you don't mind, and i'll understand if you do, but how much do you charge? and how sq ft, linear ft etc....also any tricks for getting the nice simple small vanities? i screwed up kind of and have full size large kitchens to do for my first real test. i'm nervous
Edited 12/16/2008 2:46 am ET by zynmaster
greatest thread ever. been researching online for weeks, got all the books and this thread is mo' better. i have a question. i lucked up and got a big job (4 houses all with large kitchen ct and island with a bar attached to island). i've wanted to do this for years, anyway i convinced the builder i knew what i was doing but have only done one so so job. Wow, thank you. Thanks to the other very knowledgable contributors from me. As to your job--make the road by walking, ey. Try to build one top start to finish and see what you get b4 you launch, I'd say.
any advice on transporting? I put them upright any way I can. Never flat. Usually I will put them upright against the side of my trailer, on foam blocks and secured. The smaller tops I stick in the 'xtra cab' in my truck.
whats your opinion of the diamond mesh vs rigid 4" vs rebar? it looks like you're a rebar man. This all depends on the thickness of the top. The mix--bagged mix or scratch mix--that you're using should be giving you cured concrete around 5,000 psi. Add fiber and consider the thickness of the top and then choose metal reinforcement. My tops are usually only 1 3/4 thickness. I feel if you put 3/8 or more of rebar in that thin a cross section, it weakens that area--a control joint basically. I have seen cracks show up in a perfect grid where the rebar is. I use 'pencil rod' which is like 1/4 thick. And I only put it in the long axis of the counter. I believe the strength of the concrete, cured properly and minimal metal is good. Thin remesh would be as far as I would go in a 'thin' top.
If I was doing a counter with a lot more thickness 2 1/2" or more--I'd go for more metal.
i've read the whole thread and may have missed it but could you explain the cubic ft box you were talking about earlier? the whats, whys, how's The mix that Mongo passed on by volume--rather than cheng's mix by weight--is where the box comes from. If you really want to know how many cubic feet of rock you've got, build yourself a plywood box 1x1x1 foot, dump in your material and see. I used the box to transfer measured qtys of sand into 5gal buckets mark them in graduated form so it was easier to measure out material. You'd be surprised--takes two nearly full buckets for your cubic foot.
Find the excel spreadsheet 'concrete counter calculator' in the thread for cubic foot of counter broken into materials required. One generous poster with a better handle on excel reworked that for me--looks good.
also if you don't mind, and i'll understand if you do, but how much do you charge? and how sq ft, linear ft etc....also any tricks for getting the nice simple small vanities?
I just add materials and labor, plus some OH and profit tacked on. Not very specific-just hours/days. Each counter is different with features adding more time--grinding and polishing can add a lot of time. Especially if you have to fill a lot of voids and grind again. A small vanity top is 350$ to 450$ usually.
i screwed up kind of and have full size large kitchens to do for my first real test. i'm nervous I did exactly the same and the product was no where near what I can produce now. I wish I'd had this thread then! I was armed with Cheng's book and that's it.
My advice again is to try building a few samples all the way thru and see what you get. Post as you go with questions and surely we can help you along here. Also--how LARGE are the slabs you're going to be doing? One big mistake I made was a peninsula counter about 5'x5' that I could not convince the owner to split in two slabs. It took four of us to place it and was NOT FUN> and of course it was only 1 1/2" thick and cracked all over. Character, right?
Good luck! Hope to see your progress!
whats your opinion of the diamond mesh vs rigid 4" vs rebar? it looks like you're a rebar man. This all depends on the thickness of the top. The mix--bagged mix or scratch mix--that you're using should be giving you cured concrete around 5,000 psi. Add fiber and consider the thickness of the top and then choose metal reinforcement. My tops are usually only 1 3/4 thickness. I feel if you put 3/8 or more of rebar in that thin a cross section, it weakens that area--a control joint basically. I have seen cracks show up in a perfect grid where the rebar is. I use 'pencil rod' which is like 1/4 thick. And I only put it in the long axis of the counter. I believe the strength of the concrete, cured properly and minimal metal is good. Thin remesh would be as far as I would go in a 'thin' top.
my 1st one i months ago i used the rigid 4" grid with a few rebar pieces long ways with a cheng mix. i hate the idea of paying cheng an arm and a leg for a simple cheap mix i could do myself. my CT will be between 1 3/4" and 2". the molds are made and solid and every side is perfectly flush with each other. much better than my first attempt which was a freeby job to get the experience. i'll look for pencil rod at a masonry store....its definitely not at the HD here.
The mix that Mongo passed on by volume--rather than cheng's mix by weight--is where the box comes from. If you really want to know how many cubic feet of rock you've got, build yourself a plywood box 1x1x1 foot, dump in your material and see. I used the box to transfer measured qtys of sand into 5gal buckets mark them in graduated form so it was easier to measure out material. You'd be surprised--takes two nearly full buckets for your cubic foot.
Find the excel spreadsheet 'concrete counter calculator' in the thread for cubic foot of counter broken into materials required. One generous poster with a better handle on excel reworked that for me--looks good.
grabbed the excel sheet as soon as i saw it, i've looked for something like this for a while and finally...i got both but wasn't sure about the second one until i saw an approval by you which you just did. theres absolutely no where locally to get the additives. i've seen them a while back at the depot but not anymore for whatever reason. everyone seems to use a different kind and it seems that there's several different kinds within one name i.e. pazz250, pazz 254, pazz350 etc... whats a good fiber and reducer to use (model #)? also should the first layer (the actual top of the counter) be fiber free?
I just add materials and labor, plus some OH and profit tacked on. Not very specific-just hours/days. Each counter is different with features adding more time--grinding and polishing can add a lot of time. Especially if you have to fill a lot of voids and grind again. A small vanity top is 350$ to 450$ usually.
cool, i thought i screwed up and still probably under bid a little but i just eye-balled it and quoted $1,500 per house. it worked out to be about $40 a sq ft so i lucked up but know i could have gotten more. granite here can go for $55 a sq ft and up so better to get the job than not and the quantity helps out.
nervous I did exactly the same and the product was no where near what I can produce now. I wish I'd had this thread then! I was armed with Cheng's book and that's it.
My advice again is to try building a few samples all the way thru and see what you get. Post as you go with questions and surely we can help you along here. Also--how LARGE are the slabs you're going to be doing? One big mistake I made was a peninsula counter about 5'x5' that I could not convince the owner to split in two slabs. It took four of us to place it and was NOT FUN> and of course it was only 1 1/2" thick and cracked all over. Character, right?
Good luck! Hope to see your progress!
thanks, i'll post updates. i'm doing 1 house at a time and the first one has to be right to get the other 3 so...i'm extremely happy with the molds. my first one had inconsistent sides and i didn't make enough concrete to fill flush with the top of the sides. huge learning experience. the first one will not be profitable at all but i'll have all the tools so the the other 3 should almost be complete profit (yeah me) appreciate all the help.
something that may be of help because i haven't seen it listed anywhere yet, instead of caulk for the corners where the different melamine meets i use plastilina, its a modeling clay that is oil based and doesn't dry. the local concrete CT gurus all use it instead. you can get it at the local art supply stores and also and extruder which can give you a strand of clay in the shape of a triangle which creates a beveled edge. you can also take a clay shaper ( not sure about the name but the wooden handle thingy with various metal shaped wire bent around allowing you to cut out a specific shape i.e square, round etc.) also the plastilina is great to fill in the corners of the front side to eliminate sharp corners. i've seen this done several ways but this seems the best. i was going to use another method (pvc cut into 1/4 sections and then sand the edges paper thin so they end up flush) until i ran across this. the clay is the way to go. any way thanks again
obviously you'll use the same molds for each house and new set of counters and that's thinkin wayy ahead--and thus the modeling clay for corners. That's a great idea. I'll do that if I ever re use molds. Right now I just throw them in with all my re-wood--what gets made into pellet fuel.
That quikrete mix that has the additives in it also has the fiber. I think it works good there b/c it's already in the mix, and very consolidated. I haven't had good luck when I've added my own. Always clumpy and yes, shows up in the surface of the counter if you grind and polish.
I didn't really check that excel spreadsheet #2. As long as the math matches the first one, it's right. (looks wayy better too)
I'll be interested to see what u come up with!
i'll salvage as much material as i can (i hate waste) but i'll still need to template each kitchen individualy. they're all a little different. some are 26" deep and others closer to 28" and i can't remember the last time i've seen a solid and true right angle in construction these days. i guess thats an extra benefit of the clay but with the extruder the nice consistent edges, re-usability of the clay itself, multi functional use of it (also builds up a rounded corner) and sculpt-ability its a no-brainer. at least i'm sold on it but i guess since i've never used it before i can't be to sure about. i'll let you know asap how it worked. i'll be pouring samples tomorrow, fingers crossed. one last question, mongo sent me a 12 pg guide that is absolutely fantastic and explains everything the books didn't. pretty much since reading it i've gone from nervous to rather confident. it answered all the little things that i couldn't find elsewhere. anywho....in it he list his formula as:Per one cubic foot, same ratio:
Cement - 24.4 lbs
Sand - 0.50 cu ft
Stone - 0.65 cu ft
Water - 1.33 gal (varies…I use admix and plasticizers, too…more on that later)the only thing not 100% clear to me is in the water amount listed above, does that amount include the admixtures or is that before and you have to adjust from there? he goes into it a little more but i wasn't sure if thats including the admixtures or not so.....i'm asking. i'm guessing its before and i'll have to adjust depending on what admixture i get. thats what i'll go by unless i hear otherwise so no biggy i guess. thanks again. this is gonna be fun
Edited 12/17/2008 2:40 am ET by zynmaster
"mongo sent me a 12 pg guide......."
WHAT!!! WHere's mine!?
;-)
Yes, that's the mix. As to water. I think there you have a good guideline. Once you know what you are looking for, water is a 'by eye' sort of thing. WIth countertops, you want a stiffer mix with less water in it--less shrinkage, but I htink that the cheng rec. for a 'lumpy oatmeal' mix leads you to concrete that's almost impossible to vibrate well enough to avoid voids. Especially if you're not vibrating with a specialized tool. THey use a big stinger to vibrate the whole table and that appears to work well for them. I go far wetter than 'lumpy oatmeal.'
I use my rotary hammer on 'hammer' under the cribbing or table that's holding up the mold. Best thing I've found. (if you didn't pick that out of the thread)
Why three layers of Melamine on the back edge?
Waters,I have been wanting to make a concrete countertop for ages but I have procrastinated and postponed for the longest time on the feeling that I really don't have a good grasp of the steps involved in the process. That said, I must say that I have learned more from this one thread than I have from the two Cheng books and several magazine and internet articles combined. While I was reviewing the entire thread, it dawned on me that you should be compiling the process, trick/tips, and FAQ's from other readers in one good PDF style book that others could download. I don't even see any reason why Taunton shouldn't be paying you for this info and publishing a book ("for pros by pros") combining articles from you, Mongo, Ponytl, etc. I would be first in line to buy that!If you don't mind, I looked at you Excel file and modified it to be more applicable to a beginner fabricator making only one top at a time. I'm no CC expert nor am I an Excel expert so I hope you can look it over and make sure it is accurate. I was most confused on the pigment ratio so I attempted to add that but not sure if I used the proper calculation (ratios always confuse me).Thank you so much for the great thread, I wish you were around my area so I could buy you a beer.GK
Thanks for the vote of confidence and fixin' up the spreadsheet! I don't even remember if that thing's really right...
I'd love to do an article.
Thanks,
Pat
Those are the sides I haven't screwed to the mold yet.
I do that last so I can deal with the sink and faucet knockout first.
Easier to caulk things, and you can just wipe the sawdust from drilling holes right off the mold instead of going for the vac.
Your efforts look great.
There's also a company called Vetrazzo (http://www.vetrazzo.com) that makes a similar cementitious/glass product. Probably pricey, but might be an option if you don't want the extra hassle.
Beadex all purpose joint compound (in the 1st form picture)
Never seen that....regional thing?
Yeah, one local yard carries beadex.
I like it good--except the bucket is flimsy-er than sheetrock brand's. If you like buckets... Their hot mud is wayyy better too IMHO.
That is beautiful work!......Thanks for taking the time to photo & post the whole thread. You mentioned that you don't like the templates that are usually furnished with undermount sinks. When you make your own, what kind of exposure do you shoot for?
Usually tracing the inside of the bowl will give you no exposure of the sink--or, the counter overhanging the sink by 1/8" or 1/4" This gives you some 'slop' to work with when you set the counter, which is good. In tracing this sink bowl, I used a regular pencil att. to the end of a dowel, which traced the bowl pretty 'close.' If I can get my hand in there, like with a kitchen sink, I'll use a constr. pencil which would reduce the size of the knockout, and overhang the counter more.
A lot of the templates that come with sinks, like 'blanco' for instance, will expose that beveled part of the top flange of the sink. This sucks for 'slop' for one, and also I think it's a much more functional detail when the counter overlaps the sink so that when water runs down the counter it drops straight into the sink instead of running to a lip on the sink, then down into the sink...
Cheers,
Pat"Research is what I'm doing when I don't know what I'm doing..."
Now's the time you need some muscle.
This top is small enough that two guys can handle it. I've made them large enough, 1 in particular that 4 large dudes (well, 3 large dudes and me) nearly collapsed to carry it 50'.
Be ready. Put a couple scrap 2x4's on the floor in front of the cabinet to set it on to you can rest, or revise your plan. Did I mention you should talk over your plan? Also, if you need to move the counter a subst. distance, upright is best.
Lift the counter, resting the bottom edge on your thighs and about the midpoint of the counter on the edge of the cabinet top. Now slide upward as far as you can and flop it on down. Watch your fingers.
Now you can shove the sink around if needed.
Congrats! It's there.
Now the faucet and drains go in. A single-hole faucet is really the way to go with a solid, thick counter like concrete. They usually have a very long stem and 'cup' shaped spacer/washer that will fit nicely under the counter (did I mention above that you should cut away the substrate around the faucet and sprayer for plenty of room to work below?)
If you have a 3 hole faucet like this one the plastic nuts that come with it take up a lot of room and will leave you with no space for your supply hoses. If you need to gain yourself some real estate on the faucet stems, thin conduit locknuts fit 1/2" IPS and will do the job.
On this counter I've extended the faucet stems and held the faucet itself in place with two couplings and two nipples. There are also some nice washers that the plumbing supply houses have that can help with this. Everything here snugged up nice with no leaks. Probably should have used brass tho. instead of galv.
Lastly, the 3/4 plywood substrate will now show under the counter. There are two ways around this. IF you're having/building a new cabinet, have the cabinetmaker hold the face frame 3/4 above the carcass to you can drop the substrate down behind it and it will be nice faceframe all the way up to the counter.
The other way is to put a strip of something over it. Here, as there's a copper inlay in the counter, I used a strip of sheet copper I got sheared off at the metal shop.
Thanks all for the input and interest in this thread. I learned a lot myself, zeroed in on the BT'ers that know this better than I do, and hopefully helped along a few aspiring dirtbags to build their own counters!
Cheers!
Pat
"Research is what I'm doing when I don't know what I'm doing..."
Nice work and nice thread. I'm gonna start experimenting.http://grantlogan.net/
But you all knew that. I detailed it extensively in my blog.
Next I have a vanity counter over a hammered copper sink.
Gonna do white portland and broken beer bottles, ground and polished.
That will be an experiment!
"Research is what I'm doing when I don't know what I'm doing..."
Next I have a vanity counter over a hammered copper sink.
Gonna do white portland and broken beer bottles, ground and polished.
Ewww. Pics please. I like the broken glass concept.http://grantlogan.net/
But you all knew that. I detailed it extensively in my blog.
Why couldn't you make a backsplash (maybe an inch thick) separate from the top and adhere it to the wall w/ caulk and caulk the joint. The mesh that is used for stucco would hold that together probably.?.? I would think that if you were gentle with handling it that it should work. Any ideas?
Great and inspiring thread
Dustin
Yeah back in the thread either Mongo or Ponytl said they'd had success with backsplashes. Also monolithic pours where the backsplash is integrated with the top.
I tried once and failed, and had it from another guy that he couldn't get 'em to work that long and thin...
But I think I will try again.
I think that if the piece is not moved AT ALL for a good long time in the mold, it should reach full strength and be good to go.
I would be nervous about laying it flat to grind and polish though.
I'll try it.
One of my next concrete adventures is about 50 of these molds so I can pop out some pavers for my own projects too...
http://www.designs-usa.com/Tile%20Pattern%20Paver%20Concrete%20Molds.htm"Research is what I'm doing when I don't know what I'm doing..."
I noticed that you used steel couplings under the sink. I don't think you are supposed to do that.
Maybe someone else can chime in on the use of steel there.
Recently finished my own front stair.
Used the same techniques to cast the stair treads and side lintels.
The treads are ground and polished but then finished with a clear garage floor epoxy with some silica sand in it for traction.
My daughter 'helping' to tear off the old stair... she's almost six now...
Cheers!
Pat
Those look great!
Wow, thanks so much for this ongoing thread- I've learned alot reading through it!
I am planning to cast my own concrete ctops for our new kitchen and have a few Q's you may be able to answer.
I built the cabinetry for 1.5" thick ctops, and no room for plywood underneath! I do plan to install ledger boards on the wall to support the back of the concrete. Any problem with this?
reinforcement suggestions for a 1.5" thickness?
My largest section of ctop is about 8 feet long X 28" deep, and would have a 20" X 30" cutout near the center for a cooktop. At 1.5" thick, this would be around 300lbs. I'm worried about the weight and having it break near the cutout while we move/set it. You talk about splitting the top into two pieces if it is 'large'...at what size would you make it a two piece?
I see that melamine is the standard mold material, however I'd like to use 3/4" fiberboard leftover from the cabinetry since I have an abundance of it. Is there a mold release agent that would allow this (I'm thinking several coats of shellac perhaps)?
I would like to acid-stain the finished ctops in an adobe color. Should I just use standard gray portland for the mix? Any special considerations for acid staining?
If see there are bagged mixes sold at our bix box stores, specifically for ctops. Quikcrete is one of them. Any you recommend if I were to go with a bagged mix?
With winter coming, I may be doing this project in the house. Wet polishing will be an issue. Is dry sanding an option?
Thanks for all the examples!
Shawncal--You're welcome! I'll answer your questions best as I can in your text below. (used to be able to do that with italics but I don't see that option any longer???)Wow, thanks so much for this ongoing thread- I've learned alot reading through it! I am planning to cast my own concrete ctops for our new kitchen and have a few Q's you may be able to answer.I built the cabinetry for 1.5" thick ctops, and no room for plywood underneath! I do plan to install ledger boards on the wall to support the back of the concrete. Any problem with this?
>>>Yeah, that might be a problem. Your ledger must be perfectly straight (or match the counter you cast! and then the leading edge of the cabs will do the rest of the work. Therefore the face frame and boxes are it for support. You might consider 'letting in' a piece of stout angle across the fronts from the top to provide support and tie everything togetherreinforcement suggestions for a 1.5" thickness?
>>>Look back in the thread and you'll see that I rec. 'pencil rod' from your masonry supply. It's a 1/4 thickness metal rod. At that thin the counter really just needs to be 'pinned' together in the lengthwise axis. If it's going to break it will break front to back, not the long way. Use pencil rod, or nothing for a counter that thin. Anything thicker and you'll just be putting a 'control joint' in your counter where you can expect it to crack. Use the very rich mix described in the thread or buy bagged mix of 'high early' or 5,000 psi type concrete.My largest section of ctop is about 8 feet long X 28" deep, and would have a 20" X 30" cutout near the center for a cooktop. At 1.5" thick, this would be around 300lbs. I'm worried about the weight and having it break near the cutout while we move/set it. You talk about splitting the top into two pieces if it is 'large'...at what size would you make it a two piece?
>>>> you want to make this counter in one mold, and split it at the sink. Make a knockout for the sink that goes in your mold--read back on how to do this, you can trace the inside of the bowls thru the drain hole (s) or use their template. Then put two dividing pieces of aluminum or plastic in the mold at 'nice looking' places on the sink and you'll have two pieces that can be carried around and set separately. The counter will break at the thin sink pieces otherwise--when you carry it, or after it's set anyway, so this is the way to do it. Cheng's book outlines this too.I see that melamine is the standard mold material, however I'd like to use 3/4" fiberboard leftover from the cabinetry since I have an abundance of it. Is there a mold release agent that would allow this (I'm thinking several coats of shellac perhaps)?
>>>> That would work fine. I would use water based urethane. Easy, dries fast.I would like to acid-stain the finished ctops in an adobe color. Should I just use standard gray portland for the mix? Any special considerations for acid staining?
>>>acid staining is sort of against the grain of precasting tops. Acid stains etch the surface of the concrete and you get rough surface. I would color your mix instead. You can get pretty brown with grey portland mixes. (Not 'pretty' like cute... I mean 'very'.)If see there are bagged mixes sold at our bix box stores, specifically for ctops. Quikcrete is one of them. Any you recommend if I were to go with a bagged mix?
>>>>Yes there are two I like. Quikcrete and Sacrete I think both have mixes that are good. Lowe's carry's one or the other that is actually labeled by Cheng as good for cc counters. White bag, blu lettering. Used it and it's good, but actually bags were inconsistent--couple bags were very rocky, no fines. Mix'em all and you're good. The other is home depot -- orange bag 'crack resistant 4,000 or 5,000' That's the good stuff. Has fiber too. Either of them is made better for tops with a water reducing compound added. Get this by going to your cement batch plant and begging a mason jar of the stuff off them. (bring the mason jar)With winter coming, I may be doing this project in the house. Wet polishing will be an issue. Is dry sanding an option?
>>>Cast them in the house, then bring them OUTside for the finishing process. Wet or dry you don't want that kind of mess in the house, period. Dry is an option, but only suggested if you want to polish the cream surface and not expose any sand or aggregate. Wet allows you to remove much much more material. Have fun!
If you have more questions, post here --with pictures preferably and i'd love to weigh in. as I'm sure others would too.
Cheers,
PatThanks for all the examples!