Anyone ever cut a granite counter top?

[i4ni]

Need to remove a 1/4" off the end of a granite Bath vanity top and backsplash some butchers buried in sheet rock. I removed the vanity and separated the backsplash and will cut or grind them in the garage if I end up doing it myself. Looking for advice from someone who has successfully done this as in what tools you used and what to watch out for. Idealy a wet circular stone saw with the right blade would be the best choice but finding one to rent locally isn't looking good. Most granite stores I've contacted won't touch it so my options are getting narrower.
This will set in an alcove so the cut end won't need to be polished but i want a nice straight edge with no chipout's.
Because I'm only removing a 1/4" I can foresee a potential problem with cutting it off and breakage of the thin cutoff strip do to saw vibration possibly causing more problems, especialy chipout at the ends so I'm wondering if grinding might be a better choice? Any thoughts? Thanks

 

[Lassen Forge]

Slow, calm, easy, if you can keep the cut flooded with water so much the better... DO NOT get anxious, let the abrasive blade do the work. It will be slow, but the results are worth it

 

[cgrutt]

Haven't cut granite but have trimmed marble and quartz before with a 4" diamond wheel on a grinder.

 

[manwithtools]

Calling @rlitman

 

[jar944]

It's not that hard, just cut it dry with a diamond blade. And remember to safely squint.

 

[MoonRise]

Cut it with a 50 ksi waterjet cutter.

Cutting Granite using a Waterjet Cutter - TechniWaterjet

www.techniwaterjet.com

Or buy/rent/borrow a diamond blade and use it in the appropriate power tool.

That could be a wet tile saw of a size big enough to cut through the countertop.

Or an angle grinder or circular saw (usually used dry, because electricity and water and humans typically don't play well together) with a diamond blade, usually continuous rim. Mark out the cut, rig up a guide, let the blade do the work and don't force the tool, etc, etc.

Proper PPE is essential, as always when using tools.

The Surefire Way to Modify Granite Countertops by Cutting

You've heard over and over again that cutting granite is not possible. So, is it? Read on to find out!

www.archcitygranite.com

How to Cut a Granite Countertop

Cutting granite for kitchen countertops whether indoors or outdoors—is a DIY-able job. But there are some caveats to consider before getting started.

www.thisoldhouse.com

 

[i4ni]

It's not that hard, just cut it dry with a diamond blade. And remember to safely squint.

How much did you cut off? And did you cut all the way though in one cut? The 1/4" has me a little spooked

Haven't cut granite but have trimmed marble and quartz before with a 4" diamond wheel on a grinder.

 

[BrandonV]

Proper PPE is essential, as always when using tools.

Yup. You do NOT want to breathe granite in.

 

[rlitman]

Calling @rlitman

LOL, I was already reading this thread, but really, Lassen summed it up. Slow, steady, wet*, no forcing.

As for breaking off that little piece in the end, YES, that's possibly a problem, particularly in granite, which gets kinda chunky. Support the whole piece on a surface (cardboard or styrofoam on top of plywood works, and gives your blade room to not hit the wood) so the off-cut doesn't just fall, and start your cut from the front and from above, so any chunk you need to grind back (or worse, a chunk gets torn out) ends up hidden in the back and underside. Honestly, cutting 1/4" shouldn't be a problem at all, since the off-cut doesn't weigh anything. Splitting a big piece is much more difficult.

What sort of tool to you have to cut with? A 4" angle grinder will do the job, so will a scrap circular saw. Gotta know what's in your arsenal before I make too many recommendations.

* About cutting wet: cutting VERY wet with continuous water flow works great (with the water/electricity warning above). Cutting dry works almost as well, though is VERY messy. Cutting damp is terrible. A small amount of water turns the grinding dust into a slurry that lubricates the blade and stops the cutting action.

As for what kind of a blade... A continuous rim blade isn't designed to cut dry, but go slow and it'll be fine (even if this shortens its life) and poses the least risk. I first turned to turbo blades for dry cutting, because they run cooler than regular continuous rim blades, but they don't have slots to do all sorts of damage. They kind of work, but the outcome is much rougher than a continuous rim blade makes. Then again, hidden against a wall, either will be fine. Truth be told, with a steady hand, I'd now be as comfortable doing this with an interrupted rim blade in my 4" air grinder as I would with a turbo blade in my 14" electric. It's more about being slow and steady and not forcing the cut than ANYTHING else (going full circle here).

 

[i4ni]

Cut it with a 50 ksi waterjet cutter.

Cutting Granite using a Waterjet Cutter - TechniWaterjet

www.techniwaterjet.com

Or buy/rent/borrow a diamond blade and use it in the appropriate power tool.

That could be a wet tile saw of a size big enough to cut through the countertop.

Or an angle grinder or circular saw (usually used dry, because electricity and water and humans typically don't play well together) with a diamond blade, usually continuous rim. Mark out the cut, rig up a guide, let the blade do the work and don't force the tool, etc, etc.

Proper PPE is essential, as always when using tools.

The Surefire Way to Modify Granite Countertops by Cutting

You've heard over and over again that cutting granite is not possible. So, is it? Read on to find out!

www.archcitygranite.com

How to Cut a Granite Countertop

Cutting granite for kitchen countertops whether indoors or outdoors—is a DIY-able job. But there are some caveats to consider before getting started.

www.thisoldhouse.com

I have a Ridgid Tile saw but too many variables to use it in my opinion
Thanks. I guess It's just me and the old Porter Cable skill saw. Probably should cut from front to back to prevent chip out in exposed front? Top up's OK I'm assuming?

 

[Youngandfree]

Notch the drywall and push it in.

 

[dave*99]

I used an old circular saw with a $20 diamond blade. I attached a short piece of brake line to the saw to feed water to the blade. This was connected to a plastic hose siphoning water from a spackle bucket.
Saw was plugged into a GFCI and I posted my son at the plug and told him to pull it if I started twitching.
I clamped a straight edge to the granite and made several clean cuts. The granite was sitting on a foam insulation board.

 

[rlitman]

I have a Ridgid Tile saw but too many variables to use it in my opinion
Thanks. I guess It's just me and the old Porter Cable skill saw. Probably should cut from front to back to prevent chip out in exposed front? Top up's OK I'm assuming?

Yep. You can put a layer of painter's tape on the top to prevent scratching against your saw base (even the saw bade is smooth, stone dust will get under it pretty quickly). The only problem with a circular saw is the blade is turning backwards for this job. If you can cut against a straightedge, one option to fix this is to do a shallow scoring cut before doing the full pass. That way, the up-lifting side won't tear out the top so much as it would otherwise.

Wear a dust mask, cut outside and have someone else (also with a mask) use a vacuum to collect as much dust as possible. Dust will push the saw and blade around, so keeping it clean and dry when dry cutting really helps.

 

[i4ni]

LOL, I was already reading this thread, but really, Lassen summed it up. Slow, steady, wet*, no forcing.

As for breaking off that little piece in the end, YES, that's possibly a problem, particularly in granite, which gets kinda chunky. Support the whole piece on a surface (cardboard or styrofoam on top of plywood works, and gives your blade room to not hit the wood) so the off-cut doesn't just fall, and start your cut from the front and from above, so any chunk you need to grind back (or worse, a chunk gets torn out) ends up hidden in the back and underside. Honestly, cutting 1/4" shouldn't be a problem at all, since the off-cut doesn't weigh anything. Splitting a big piece is much more difficult.

What sort of tool to you have to cut with? A 4" angle grinder will do the job, so will a scrap circular saw. Gotta know what's in your arsenal before I make too many recommendations.

* About cutting wet: cutting VERY wet with continuous water flow works great (with the water/electricity warning above). Cutting dry works almost as well, though is VERY messy. Cutting damp is terrible. A small amount of water turns the grinding dust into a slurry that lubricates the blade and stops the cutting action.

As for what kind of a blade... A continuous rim blade isn't designed to cut dry, but go slow and it'll be fine (even if this shortens its life) and poses the least risk. I first turned to turbo blades for dry cutting, because they run cooler than regular continuous rim blades, but they don't have slots to do all sorts of damage. They kind of work, but the outcome is much rougher than a continuous rim blade makes. Then again, hidden against a wall, either will be fine. Truth be told, with a steady hand, I'd now be as comfortable doing this with an interrupted rim blade in my 4" air grinder as I would with a turbo blade in my 14" electric. It's more about being slow and steady and not forcing the cut than ANYTHING else (going full circle here).

I guess my 7 1/4 P/C skill saw will be the guinea pig and dry cutting the method . Will probably do it outside with a strong fan to help with the dust. Blade yet to be determined because I have a brand new diamond here somewhere. I have no idea what it be so if I have to buy a better one thats what I'll do along with the rest of your recomendations. Thanks alot

 

[Firstram]

I guess my 7 1/4 P/C skill saw will be the guinea pig and dry cutting the method . Will probably do it outside with a strong fan to help with the dust. Blade yet to be determined because I have a brand new diamond here somewhere. I have no idea what it be so if I have to buy a better one thats what I'll do along with the rest of your recomendations. Thanks alot

Plug the saw into a GFCI protected outlet and cut it wet! Dry cutting really *****!!!!!

 

[i4ni]

Notch the drywall and push it in.

Thats the way it was and was cracking around the mud. It was just too tight a fit to get it out so I ended up having to remove the sheetrock to free it enough to get it out.

 

[manwithtools]

Plug the saw into a GFCI protected outlet and cut it wet! Dry cutting really *****!!!!!

Or, you could buy a cheap cordless saw and cut it wet that way.

 

[rlitman]

Plug the saw into a GFCI protected outlet and cut it wet! Dry cutting really *****!!!!!

Dry cutting makes an enormous dust cloud, and the fan would help a little, but a vacuum on the saw's dust port (if it has one) can help a lot more (you can even tape some cardboard over the big guard opening to keep the dust in). If it's a plastic saw that's double insulated, then yeah, GFCI should make wet cutting safe enough.

I'm not sure what's worse for your saw, the dry dust or the wet... I don't think I'd abuse my nice magnesium PC like this, but a $15 garage sale orange plastic Skill, sure, why not.

 

[engineer2]

I've done it with a 7" diamond blade using my table saw. For safety reasons I plugged the saw into a GFCI and had the wife hold the garden hose dribbling water. Dried the saw off afterwards. No harm done.
I didn't own a tile saw back then, but nowadays I would just use my tile saw with a helper and/or a roller table. It'll do a 24" cut.
Another way is to use a 4-1/2" grinder with a diamond blade and clamp a guide to the piece.

 

[jar944]

How much did you cut off? And did you cut all the way though in one cut? The 1/4" has me a little spooked

That was 6" off one side and a couple feet off the other.

These just needed a trim.


The center bridge on this one needed about 1/4" off the length and the the cut squared up along with a notch in the back cut. Same cheap skill circular saw cut dry and a continuous rim diamond blade.

 

[finn]

I have done a couple on vanity backsplashes with a cheap ($12?) HF 4” grinder and a $20 diamond wheel. Messy, but no problem.

More recently, I bought a cheap wet saw off CL. Nicer to use, since it has a water bath. That setup cost $20. I think you can rent a nicer one, but it seems I have used the wet saw quite a few times.. Almost enough that I wish I had bought a nicer one.

 

[i4ni]

Dry cutting makes an enormous dust cloud, and the fan would help a little, but a vacuum on the saw's dust port (if it has one) can help a lot more (you can even tape some cardboard over the big guard opening to keep the dust in). If it's a plastic saw that's double insulated, then yeah, GFCI should make wet cutting safe enough.

I'm not sure what's worse for your saw, the dry dust or the wet... I don't think I'd abuse my nice magnesium PC like this, but a $15 garage sale orange plastic Skill, sure, why not.

Thanks, that reminds me I've got a Ridgid worm drive I took a chance on in a closed box store returns auction that was a bust. It actually looks like it spent it's whole life doing just what we've been talking about,lol. I'll dig it out and see if it's got enough life in it for one more cut

 

[Sturgeon]

It's dusty work, visquine off work area and liberally spray cutting area while cutting. Easier on the saw blade and helps to minalize dust. As mentioned straight edge ++++.

 

[u3b3rg33k]

Yup. You do NOT want to breathe granite in.

Dry cutting makes an enormous dust cloud, and the fan would help a little, but a vacuum on the saw's dust port (if it has one) can help a lot more (you can even tape some cardboard over the big guard opening to keep the dust in). If it's a plastic saw that's double insulated, then yeah, GFCI should make wet cutting safe enough.

I'm not sure what's worse for your saw, the dry dust or the wet... I don't think I'd abuse my nice magnesium PC like this, but a $15 garage sale orange plastic Skill, sure, why not.

If you don't like getting lung cancer, another vote for a REAL respirator (P100) with a silicone seal, and wet cutting.


something like that. apparently counterfeits are a thing if you buy on suspect websites.

 

[Zeke]

When I see these tile, block. brick and solid surface hacks cutting dry I want to slap them upside the head. Out on a farm maybe. Use a stream of water, stay on high and dry ground and use the GFCI. You won't have any trouble with today's plastic double insulated power tools.

Don't let the detritus dry inside the saw or grinder guard. Clean it out with water and a toothbrush. Take the guard off it is a circular saw. Spray it down with WD40 when clean and blow off. Your tool will look like it never cut stone. Dry cut and it will eat stone dust. Not good for it or you.

 

[i4ni]

I have done a couple on vanity backsplashes with a cheap ($12?) HF 4” grinder and a $20 diamond wheel. Messy, but no problem.

More recently, I bought a cheap wet saw off CL. Nicer to use, since it has a water bath. That setup cost $20. I think you can rent a nicer one, but it seems I have used the wet saw quite a few times.. Almost enough that I wish I had bought a nicer one.

I'm way too shaky anymore to use a grinder for this critical of a cut. I've got a brand new Ridgid Tile saw that I bought at the same auction as above that someone returned that other than having alittle drywall mud on a couple spots doesn't appear to have ever been used. With that said I think using it would turn into a sideshow of problems trying to cut the vanity itself but would probably be ok to cut the back splash.

 

[duneslider]

It all depends on how perfect you need this to be. I have done lots and lots of trimming with grinders and diamond blades, and yes mostly with dry blades, really not that big of a deal. Holding a vacuum near the cut will get almost all the dust that is made.

However, I also have a small 4" wet circular saw that works great for this sort of thing too. Just clamp a board on the piece for a guide and you should get a pretty nice cut. I wouldn't cut this inside the house (wet or dry).

 

[finn]

I'm way too shaky anymore to use a grinder for this critical of a cut. I've got a brand new Ridgid Tile saw that I bought at the same auction as above that someone returned that other than having alittle drywall mud on a couple spots doesn't appear to have ever been used. With that said I think using it would turn into a sideshow of problems trying to cut the vanity itself but would probably be ok to cut the back splash.

Probably need to construct some sort of larger table to insert the saw in. That would stabilize the large countertop.

 

[cgrutt]

How much did you cut off? And did you cut all the way though in one cut? The 1/4" has me a little spooked

I've done several bathroom vanities and kitchen backsplashes etc. 1/4" should not be a problem you can leave line and grind up to it if you want to.

 

[jonesg]

I used an old circular saw with a $20 diamond blade. I attached a short piece of brake line to the saw to feed water to the blade. This was connected to a plastic hose siphoning water from a spackle bucket.
Saw was plugged into a GFCI and I posted my son at the plug and told him to pull it if I started twitching.
I clamped a straight edge to the granite and made several clean cuts. The granite was sitting on a foam insulation board.

can't be done, its not possible they all said.
i did the exact same thing using nicop copper tube and 1/4 clear hose, gravity feed water to cut a concrete floor.
dewalt diamond blade. Very little dust, mostly slurry, saw never got wet.

 

[BrandonV]

When I see these tile, block. brick and solid surface hacks cutting dry I want to slap them upside the head. Out on a farm maybe. Use a stream of water, stay on high and dry ground and use the GFCI. You won't have any trouble with today's plastic double insulated power tools.

Don't let the detritus dry inside the saw or grinder guard. Clean it out with water and a toothbrush. Take the guard off it is a circular saw. Spray it down with WD40 when clean and blow off. Your tool will look like it never cut stone. Dry cut and it will eat stone dust. Not good for it or you.

I had a company install a couple hundred square feet of concrete pavers.

I offered them 3M respirators they refused saying they got too hot.

I don't know how you can do that everyday and not get sick.

 

[i4ni]

Probably need to construct some sort of larger table to insert the saw in. That would stabilize the large countertop.

I havent ruled it out yet.

 

[Old Man Roger]

I didn’t read the whole thread, but it sounds like it might be easier to move the vanity a little?

 

[i4ni]

can't be done, its not possible they all said.
i did the exact same thing using nicop copper tube and 1/4 clear hose, gravity feed water to cut a concrete floor.
dewalt diamond blade. Very little dust, mostly slurry, saw never got wet.

I've ground concrete wet no problem.

 

[i4ni]

I didn’t read the whole thread, but it sounds like it might be easier to move the vanity a little?

No it sets in an alcove

 

[i4ni]

I had a company install a couple hundred square feet of concrete pavers.

I offered them 3M respirators they refused saying they got too hot.

I don't know how you can do that everyday and not get sick.

I worked with an old boy years ago that alls he did for years was saw concrete and he sounded like he had a bowel of gravel for breakfast everyday. He died from either that or his life style. "Good Ol Bear" Super nice guy.

 

[i4ni]

I've done several bathroom vanities and kitchen backsplashes etc. 1/4" should not be a problem you can leave line and grind up to it if you want to.

Thanks

 

[Walkers]

I cut and polished my kitchen island. I just used a 7-1/4” diamond blade in a circular saw. Clamp a guide to it if at all possible. Also protect the top fully. Blue tape would work fine, otherwise you will have a dull line that is hard to get out from the shoe vibrating on the top.

 

[nadogail]

I have a $10 Harbor Freight Angle Grinder that spins a $40 carbide disc that does a nice job on concrete. It will also cut granite to size.

 

[dcg9381]

I "just" did this, I had some left over slab for the house and dad wanted to cut up some of it for a bathroom at his place.
Basically bought a wet makita saw/blade, and went at it. No fancy edge on it, just straight cut. Polished the 90 degree edge eventually. It looks like tools cost <$200 and that's for the blue-ish brand.

Honestly, what got us, slabs have fractures in them, so you really need solid support, we had to make one additional cut when a corner came off..


I live on a "border state" so there's a big difference in the companies that are contracting the labor to the people doing the labor. Small job, I'd be poaching guys from larger install jobs. Around here, they arrive with the tools and an F-150 and would do what you need for a few hundred dollars (if that).

These were the slabs (spare) that I gave him to cut up: