Hey Mongo..concrete counter question..
Hey…
Finally getting ready to make the counter-tops…(I know, it’s taken me awhile to get there). I can’t seem to find a form for my sinks. Was thinking of making templates with a few layers of thick plywood….glue and screw together….but what to do with the edges? Cover them with something that will allow form to release and be smooth. Any ideas? What other options are there?? As for fixture holes, pvc with different widths an opening to accept a basin wrench. Any help is greatly appreciated. Seem to be a bit nervous about starting my first ones. They are going in a flip house, not mine.
Replies
Fu Tung Chen, the concrete countertop guru, makes most of his forms from melamine and covers any exposed wood with clear packing tape. His book is worth the money if you are planning to do concrete counter tops.
Kevin Halliburton
"Do you see a man skilled in his work? He will serve before kings; he will not serve before obscure men." - Solomon
Thanks Kevin...I actually took Chengs workshop...The problem being, they have there forms all worked out, and currently don't carry them, but they said they will soon. I just needed to get a handle on other ways as opposed to having to buy the forms. And thanks to breaktime.....that doesn't seem to be a problem.
Beck
They're going to sell forms?
Wow.
I'll be even more suprised if people buy them.
Remember, this ain't rocket science. However, it does require a bit of forethought, accurate measuring and layout, and attention to detail.
From the looks of their web site they sell just about everything. Hey, this is America - people here buy their salads pre-made for crying out loud.
Buy the way, thanks for all the excellent info in this thread so far. I'm bookmarking it for future reference.Kevin Halliburton
"Do you see a man skilled in his work? He will serve before kings; he will not serve before obscure men." - Solomon
I'd like to do the same.....how to bookmark? (I swear there are things I CAN do......I'm just not sure what they are currently)
Go to the first post in this thread, right click over the number in the upper right hand corner (41520.1) and select "copy shortcut" from the pop up menu. Right click over your browser address bar and "paste" the shortcut into that bar then hit "Go." This will insure the page that gets bookmarked is this thread, not the one you clicked on when you first opened Breaktime.
Now go to the top of the screen and click on the "Favorites" menu and select "add to favorites."
It's not the shortest route but it's one of the easiest to follow.Kevin Halliburton
"Do you see a man skilled in his work? He will serve before kings; he will not serve before obscure men." - Solomon
"...people here buy their salads pre-made for crying out loud."
<g>
Where are you able to get gloss laminate? I am in the boonies, with some basic lumberyards near by, and the nearest homecenter is Lowe's, one hour drive. The nearest Depot is two hours. The stuff I see stocked at Lowe's is not gloss.
Never been to Lowes, HD carries it in stock. Local lumberyard will special order it, but again, I'm looking for the cheap stuff. I get it at HD. If they have sheets where the edges are dinged, that's even better at 50% off.
Melamine gives a good smooth surface, it's certianly usable.
You're right about melamine. I've used it, but it has the same surface texture as the matte satin stuff that Lowe's stocks. I will try Depot next time I ferry across.
For vibration, I have tried a random orbit sander on the bottom side (didn't work), and a big flexwand vibrator of the kind used when pouring foundation walls, just touched it to the form bottom. That was kinda violent.
I've a little 1/4 hp 1725 rpm Dayton motor sitting around doing nothing. If I figure a way to mount an eccentric weight on the shaft (I was just thinking of some lagscrews and duct tape), how should I use it with the form?
Instead of attaching it to the form, where you might get uneven, or localized vibration...or worse yet, it might shake the form apart...I mount mine to the table that supports the form.
That way, as the table shakes, it vibrates the entire form on a fairly even basis.
Some people have reported success using a bladeless sawzall to whack the sides of the form.
Years and years ago, I used to use a hammer.
Yea.....I hate to even tell you what I paid for the "mixen's". Since these are my first ones, and I am eyeball deep in a total remodel of this house, I wanted to go the easy way. So, pick a color, type in sq. footage, and "POOF", you get all the mixen's for your counter. After this, though, I'll be creating my own as I learn and figure stuff out. As for the Formica colors, I'm sure folks just think, "he's got more money than taste....and it appears he doesn't even have money". Good thing you go to a big box....Many folks with the same "problem". As for Cheng selling forms....have you seen his Tea Tasting room??? Obviously he's strapped for cash....NOT! Beck
If the sinks are drop-in, detailing the edge really doesn't tmatter. It can be a bit rough, as the drop-in sink will cover it up. In this case, depending on the shape of the sink, you can form the sink rim out of 2-bys (if close to rectangular), or from layers of ply (if oval). If 2-by, you can leave the edges as is. If ply, run tape around it to act as a release so the mix doesn't stick to the rough edge of the ply. If you wrap the sink blank in a couple wraps of 1/8" packing foam, or foam sill sealer, then tape over the foam, the "give" of the foam will make it easier to remove the sink blank from the cured countertop.
If the sink is an undermount, then the sink edges will be exposed and they'll have to look purdy. I line the edges with gloss formica. Actually, I line the entire mold with gloss formica. The formica is cheap, $20-$30 a sheet, and can be reused several times.
Formica gives a primo finish surface. Much smoother than melamine and other materials, and that means no grinding or polishing.
Do the plumbing holes as you mentioned. Don't forget the relationship between the thickness of the countertop and the length of the threaded nipple on the plumbing fixtures. If the top is 2" thick and the nipple is 1-1/4" long, you won't be able to thread the nut on the nipple. In that case I make the plumbing stubout that you'll screw to the form look like an upside-down wedding cake.
I'll try posting a few pics later.
#8 shows a somewhat close-up of the form frn an undermount sink. Since the edges will be exposed, it's wrapped in formica that was contact cemented to a 2-by frame shaped with a bandsaw and beltsander. You can also see two "wedding cake" stubouts for plumbing, one for the faucet, one for a soap dispenser.
#9 is an overview of the form. The large rectangular cutout is for a cooktop. Unfaced,m since the cooktop is a drop-in and the edges will not be exposed.
#10 is the form being filled. As shown there's about 3/4" of mix in the form, then the hardware cloth and the rebar were installed. Total thickness will be 2".
Wanted to add a note:
Regarding pic#8, with the undermount sink form. You can see that the INSIDE of the sink form is open, and that it was assembled with screws.
You probably already figured it out, but after the slab has cured, simply back out the screws and take the pieces out one by one.
Makes it much easier than trying to remove a solid form surrounded by concrete.
Or, if you go the stacked ply route, you can later cut the ply out with a jigsaw or something similar by sectioning it out in peices.
And what is your method for getting all the air out of the concrete, so as to get zero bubble holes?
Use a plasticizer which does a couple of things...it improves the flow characteristics of the mix, which means fewer trapped bubbles from the start. It also allows the mix to flow better with less water, which means a stronger slab.
I vibrate the form with an old washing machine motor. Mounted an eccentric weight on the motor, so when the motor operates it shakes the table.
Big thanks for the info and pics. I think I'm ready....(course' sitting here sippin' on a cold beer might have something to do with that.) The formica....? Thin sheets....what is it placed on top of for strength? Ply? I like the idea of no polishing/grinding, although I did just buy a nice 7" wheel.
Will not only do these, but will learn how to post pics as well. Once again thanks, and I would bet you'll be hearing from me again. Beck
You can place the formica on top of a sheet of 3/4" ply, and place the ply on top of a sturdy table, or WELL SUPPORTED sawhorses, or a torsion-box table...whatever you choose, as long as the ply will be flat and properly supported.
To screw the rim to the base, screw through the ply, through the formica, up and into the 2" rim. Screw about avery 4"-6", and if you want, before you screw, run a bead of caulk between the rim piece and the formica bed. The caulk is to prevent liquid from the mix from seeping out of the form. Normally not required with a tight form, but it's good insurance.
I tried several materials for the form. A cheap sheet of gloss formica provided an absolutely glossy, dead-flat, mirror-like surface in the final slab. After uncrating, let the slab dry a bit, as it will still be a bit moist. Then if it's too glossy, take the surface down a tad with abrasives to get a honed or matte look. I don't mean grind...you just need to add enough scratches to reduce the reflective properties. Even fine-grit paper on a ROS will do that on somewhat fresh concrete. Again, the goal is to add microscopic scratches, not physically grind material off the surface.
The worst thing about using formica? I buy the cheapest sheets of gloss formica I can find, based soley on price. As a result I end up at the register with some pretty funky color combos, with people at the register wondering what poor person hired this fool to do their kitchen countertops?
I'll try another rough graphic regarding form construction...and I emphasize "rough"<g>:
This is the only pic that I can't seem to open. Tried everything, but no go. Strange, as everything else opens fine. Will be out of town for a few days, (Funeral) but will be back on board Monday or so. Appreciate all.....actually starting to get excited about starting them. Am assuming ROS is an orbital?? Beck
It's a MS.pub graphic with cross-sections of typical form construction, so you may have to download it in order to open it. Not sure.
If you still can't view it and you want to, email me with your home email and I'll email it to you. Can't do it through Propsero's email link, as they don't allow attachments.
Can't emphasize enough doing a few samples to work out the bugs before you tackle the 'big one'. Every little bit helps, and you;ll get a few stepping stones for the garden for your efforts.
You got it, ROS = random orbital sander.
I'm leaving today as well, be back Tuseday then out of town again Thursday.