cutting granite

[Roger Barga]

Is it possible to trim slab granite (1" thick) with a circular saw?

I purchased up a stunning granite slab remnant and wish to use this as a top for a sideboard. However, the cost to cut a usable top from this remnant is roughly equal to the cost of the granite remnant itself. A friend suggested it might be possible to do this myself using a circular saw, but I don't want to risk a crack or damage without first knowing whether it's possible to 'do it yourself'. Any advice would be appreciated.

thanks,
roger

[Rob Russell]

Roger,

The problem isn't just cutting the edge, it's likely also finishing the edge.

The stone places near us, for example the one we got our granite counter tops from, use water-cooled diamond impregnated saws to cut the big slabs. I don't know what they use for shaping the edges - whether those are diamond also or carbide.

If your sideboard would have a recessed slab, with wood edging around it so the edge of the granite doesn't need to be finished, you could get a diamond blade for your circular saw. That would be one dusty cut. I'd wrap the motor vent intakes with some cloth and wet it to keep the granite dust out of the motor.

Personally, I'd call a stone place and ask them how much they'd charge to cut the slab for me. If you're looking for a finished edge on the slab, that's the only way I can think of doing it, 'cuz I don't know how they polish the edges and that's not something I want to wet-sand by hand. You may also be able to find out from a stone place if carbide works to cut granite.

Just some thoughts,

Rob

[Mike Weaver]

I'd have to agree with Rob's comments, with one further suggestion... It might be possible to rent a suitable saw from your local "Rent All Mart" - that way you don't kill your circular saw. The diamond blades themselves are a bit pricey, IMO, for one cut and you might be able to rent the saw for less?

Anyway, if you can, please post pics - I have some pre-trimmed marble slabs that are destined for coffee and end tables..... someday, and I'd love to see what you're doing.

Cheers,
-Mike

[John Renzetti]

Hi, The only thing I can add to Rob's comments are that the company that cuts and polishes the edges will likely offer no guarantee that the slab won't crack while they are cutting it. With these natural materials there can be hidden fissures or other imperfections that won't show up until the fabrication work is started.
take care,
John

[John Hart]

I've found myself cutting a lot of rock...mainly for geological purposes...but I bought a table top tile saw with a diamond blade (sorta looks like a mini TS). Anyhoo, it cuts most anything, even granite and it's water cooled but the diamond blade has a tendency to chip the stone sometimes. I used my circular saw with a masonary blade a couple of weeks ago....It didn't chip the stone but did like to drift. Once I got my fencing figured out, it went pretty good. I finished the edge by tilting the blade and ran it along the edge. (even though you're not supposed to do that as it is unsafe ) My biggest gripe with the circular saw was that I couldn't pour water on the project while doing it. If I had to do it again, I'd rent the right tool as Mike suggested. HD carries that rental stuff too (4 hours for about $25).

[James Mudler]

http://www.diygranite.com/ and ebay has the polishing pads. Another trick is cut it, then spread expoy over the edges. Sometimes you can skip the polishing.

[Andy Henriksen]

I got a (I like to think) stunning peice of granite myself not too long ago and trimmed it up with a diamond blade on the circ saw. It worked pretty well, but I had a problem with the saw sorta riding up a bit, so the cut ended up not being a perfect 90* to the face. I tried to take about as shallow of a cut as possible too and did probably 10 or more passes.

Were I to do it again, I would be sure to put more downforce on the saw to keep the blade cutting in the correct orientation. For my intended app, the rough edge is fine, as is the slightly beveled edged, as I will be banding all around with wood (plan to make a bar top). On that edge, the wood will have to have a corresponding back bevel of a few degrees, to make up for the it.

It is, as other's alluded to, one of the dustiest things you'll ever do. Do it outside at all costs, no matter what a pain the thing is to move. And try to run water over the slab as you cut (easier said than done).

[Roy Wall]

We installed granite tops throughout our house 10 years ago.. We cut 1 1/2" slabs with the circ. saw and diamond blade..

Outside with a trickle of water from the hose......slowly - with a lot of downward force like Andy mentioned....

All the front edges were band with Corian...

[Neal McCormick]

I just had a new front sidewalk installed. The one step up to the porch is an old granite curb from downtown Cleveland. The granite had to be trimmed by about 6 inches across the length (about 5 feet). The guy doing the installation used a chalk line to mark the slab and then a Stihl concrete saw (gas powered). And the dust flew!! I know my local rental center will rent the saw and the blade to you. It might be cheaper, as mentioned previously, to buy a blade yourself. The blade my installer used cut through the granite without much difficulty.

[Frank Hagan]

I hired three installers to do a side job ... putting in a 'pull up' granite countertop in my kitchen (my SIL has too much money, so she decided her brown granite didn't match her new stainless appliances, so she ripped it out and put in black granite).

It was a job contractors didn't want to do because of liability, as they couldn't guarantee results. They were afraid it would break just from handling.

The guys I hired are the workers, and they do this all day long. They use a 4" grinder from HF. No kidding. They put masking tape where they are going to cut, draw a line, and hand hold the grinder with a diamond blade on it and pull it through the cut. I asked if the masking tape helped prevent chipping, and they laughed; it was just so they could see the line.

Where they made a butt joint, they "cheated". They cut on a slight angle ... 5 degrees maybe ... so the top was easy to grind down to match. They used the kind of grinding and polishing wheels you can buy on that http://www.diygranite.com/ site mentioned earlier. I would imagine putting a different edge treatment would be a different kind of thing, but they made it look easy.