Replies

1. 
   RichMast | Aug 25, 2003 04:43am | #1

   yup.  I have only seen them on television shows showing stone countertop fabrication.  A quick web search led to http://www.granitecitytool.com which had diamond router bits. I'm sure that there are special routers used with water cooling, which you would definitely want to check out considering the cost of the bits at over $100.

   Hope this helps.  Rich.

2. 
   HeavyDuty | Aug 25, 2003 04:52am | #2

   Definitely. That's what they use to work on granite. I think they do it dry though, special router for sure. For a computer controlled machine, they probably do it wet. Let's hear from some granite fabricators.

   Tom

1. 
   luvmuskoka | Sep 07, 2003 08:02am | #7

   My wife sells stone. I'll post some pics of the operation later in the week. You should see the "waterfall" dust collection system.Ditch

1. 
   FastEddie1 | Sep 07, 2003 04:34pm | #8

   My wife sells stone.  Ok, a second question...  HO wants something a little different for the kitchen island counter.  Limestone is (relatively) plentiful around here, so I was thinking about using a slab for the island, thinking I could probably shape it with my grindr and appropriate blades and wheels, then sand & polish the top and apply a good stone sealer.  Any idea if the limestone would work for a counter?Do it right, or do it twice.

1. 
   MarkH128 | Sep 07, 2003 04:51pm | #9

   Limestone counters are quickly gaining popularity around here. Good luck trying to make one yourself, but I think it may be possible.

2. 
   luvmuskoka | Sep 07, 2003 07:10pm | #11

   Granite is now in line with solid surface, cost wise, so of course it's becoming more and more common. Which is a good thing... and.... a bad thing.

   Good thing:  They can't do kitchens fast enough.

   Bad thing: They're now pressured to find the next best thing.

   I've watched them cut and finish limestone....or rasp, is more the term. A huge chisel hangs over a giant steel bed, which is motor driven, and moves the slab back and forth under the chisel. Each pass takes about 1/32" of an inch off the slab. To cut a bevel on the edge of the slab, the chisel is positioned at the appropriate angle.

   It definitely doesn't look like something you could do yourself, unless you were making small pieces.

   Ditch

   Edited 9/7/2003 12:11:34 PM ET by luvditchburns

1. 
   FastEddie1 | Sep 07, 2003 07:52pm | #12

   Never let ignorance get in the way of determination.

   Well, the fact that they shape limestone with a rasp tells me that it could be done in my garage/shop/backyard.  I was thinking about getting a slab from my local stone yard, then cutting it to shape (an arc)  and finishing the edges with an abrasive masonry wheel and various grits of silicon carbide in a belt sander.  I guess my question to your SWMBO was...is the limestone durable enough for a kitchen island counter?

   Do it right, or do it twice.

2. 
   luvmuskoka | Sep 08, 2003 04:44am | #15

   O.K. Here's my wifes take on limestone tops. It chips easily. It requires more maintenance than granite, something most homeowners neglect soon after they start using it. Lack of proper maintenance will also lead to staining.Ditch

3. 
   HeavyDuty | Sep 07, 2003 07:53pm | #13

   Limestone backsplashs and counters are the in things right now, especially with those old world look kitchens. It's much softer, in look and in term of hardness than granite. Just watch out that they stain quite easily so a good sealer is in order.

   Tom

   Edited 9/7/2003 12:54:06 PM ET by TOMCHARK

4. 
   migraine | Sep 07, 2003 07:59pm | #14

   I know that one of my fabricator buds uses some carbide router bits on limestone.  But, I don't know if they can be used on all types of limestone.  I haven't tried it yet, but soon..

5. 
   KARLSTER | Sep 08, 2003 07:31am | #16

   I have put in limestone countertops.  The thing I couldn't get the homeowner to realize is that her limestone is going to chip, stain, scratch and show all of her usage patterns.  She was determined that through care and maintenance she would keep it looking like brand new.

   What is so silly is that the "Old World" kitchens that she is trying to emulate are so beautiful and have so much character because they show all the scars of decades of daily use.

   No sealer will protect the more porous limestones from absorbing spills.  In fact it can be detrimental to apply a totally impervious coating to the limestone as the stone will get softer and degrade due to a process I don't fully understand.  Bottom line is the stone has to "breathe".

   My slab supplier maintains that the French never seal their limestone counters. They just throw a big housewarming party, spill red wine, olive oil, butter, etc all over the countertops, pass out drunk and clean it up the next morning.  The brand new limestone looks nothing like it did the day previous as it is covered with stains, scratches and blotches.  After a few hundred meal preparations the counter has its own unique and beautiful patina that will easily hide a spill or scratch as there are so many already their ahead of it.

   I can't imagine trying to surface a slab.  I just buy 2 cm thick slabs for around 7 dollars a square foot and cut them to shape and do any edging.

   I recommend you use a 7" silicon carbide disc rather than a belt sander.  I use a pistol grip makita sander with a porter cable fiberglass backer pad but you could use a 7" angle grinder as well.

   Good luck, Karl

1. 
   gbwood | Sep 08, 2003 10:40am | #17

   not the best pics, but here is a limestoned kitchen

   
3. 
   KARLSTER | Aug 25, 2003 07:38am | #3

   I have a selection of diamond router bits I use for edge profiling granite.  I run them in a Flex (marketed by Porter Cable) router.  The router costs around 1250 dollars and the bits start at 350 dollars but I have paid up to 650 dollars.  This is the least expensive water fed router I am aware of.  Some outfits market a Porter Cable 3hp woodworking router retrofitted with a water feed but I have never seen one in operation.  The diamond abrasives typically run between 6000 and 9000 rpm.

   Concrete is so abrasive that it would quickly eat up the matrix in which the diamonds are suspended.  In other words, routering concrete would wear out the router bit far faster than any granite worker ever would.  Granite is very hard but not abrasive.  In some cases it is necessary for granite fabricators to run a diamond abrasive against concrete every so often to wear away the matrix suspending the diamonds and expose fresh "sharp" diamonds.

   I saw someone mentioned Granite City Tool.  Their prices are as cheap as anyone for diamond abrasives unless you compare them to Harbor Freight (they don't sell diamond routers, just saw blades, burrs, drums, etc).

   What specifically would you hope to do on concrete with a diamond router?

   Karl

1. 
   FastEddie1 | Sep 07, 2003 05:57am | #4

   Just thinking.  During the planning stage of the remodel, HO asked if the floors could be stained.  We didn't go that route, but I was wondering if we had, would she have wanted a pattern cut in the floor, and would there be an alternate to using a diamond wheel or however it is done, because my interpretation of the typical method is that curved lines are difficult.

   Do it right, or do it twice.

1. 
   BillHartmann | Sep 07, 2003 07:43am | #5

   I saw on one show where they had a thick steel stencil and they used needle scaler to "etch" the concrete and remove the stain.

   After the stencil was removed he used a small flex shaft grinder to finish up where the "bridges" where in the stencil.

2. 
   KARLSTER | Sep 07, 2003 07:49am | #6

   I am getting a little outside my area of expertise addressing concrete questions(I am more familiar with cutting/shaping/polishing granite) but I would try to find a way to cut the pattern with a circular blade.  I don't know what kind of radius you want in your curves but you can get dished 4 to 5" blades that might help with tighter radii.

   The only diamond router bits that I see with any potential for doing a lot of lineal footage are 1" in diameter so you won't get very fine lines going that route.  These bits are also designed for high horsepower CNC machines.  There are a lot of diamond electroplated bits for die grinders and they might cut finer lines but they won't have much longevity.  Harbor freight has a surprisingly diverse selection of diamond abrasives of relatively cheap quality but adequate for most experimental projects. 

   One diamond abrasive they sell I whole heartedly recommend to other stone fabricators is a set of 3/4 by 1" and 1 by 1" diamond drums for about 7 dollars.  I put mine in a drywall cut out tool and it is hard on the bearings but it gives about an 80 grit finish and I don't know of any other tool that will grind that tight a radius in stone.  They last surprisingly long as well even cutting dry.

   Sorry I don't have any bright ideas on the concrete patterns.

   Karl

4. 
   Egg | Sep 07, 2003 06:01pm | #10

   Try this one as a source.

   http://www.masterwholesale.com/mw/mwi_router_bits.html