Cutting Granite Counters

[erkevin]

Actually Silestone. Here is my plan- I welcome comments.
I have to enlarge an existing cut-out for a new range install. Definitely has to be wider (2 cuts), but may also need to be deeper (3rd cut). I am going to use an angle grinder with a diamond blade. I am doing this as a dry cut, as there are no GFCI outlets nearby. As I cut, my wife will hold a vacuum hose near the rear of the blade to catch as much dust as possible. We are going to put up plastic in order to contain as much dust as possible also. We will have P100 masks on and eye goggles. I will do a shallow cut first as it will act as a guide for the complete cut. Cuts will be marked on painter's tape to protect from chips, etc. Fortunately, the rangetop has lips (overhang) so I do not have to be pretty or perfect in my cuts.
What have I forgotten?

 

[omni550]

I have no experience with Silestone.

Google found these. Perhaps there's a helpful tip or two here....

https://www.hunker.com/13402834/how-to-cut-silestone-countertops

https://www.thesawguy.com/how-to-cut-silestone/

http://www.nssurfaces.com/wp-content/uploads/2015/06/ManufacturingMachinery.pdf

Good luck.


omni

 

[erkevin]

The first two I have watched and studied. The manual, I have not seen. Thank you.

 

[RobbieB]

You can always make a portable GFCI with an electrical box and an extension cord. I'd go wet, my granite cutters did and have your wife on it with the wet shop vac.

 

[travelover]

You can always make a portable GFCI with an electrical box and an extension cord. I'd go wet, my granite cutters did and have your wife on it with the wet shop vac.

Yes, there are plug in GFCI adapters that just plug into an existing outlet. https://www.amazon.com/TRC-14650006...=gfci+adapter&qid=1567102201&s=gateway&sr=8-4

 

[erkevin]

OK, that may be a game changer. I did not know that they exist! Thanks guys (girls).

 

[travelover]

OK, that may be a game changer. I did not know that they exist! Thanks guys (girls).

You probably want GFCI outlets in a kitchen anyway. Relatively easy to replace an existing outlet.

 

[davebarnes]

I would just gut and reno the entire kitchen.
We did that because the microwave handle broke.
Hire professionals.
Blow that dough. ( https://www.financialsamurai.com/the-fear-of-running-out-of-money-in-retirement-is-overblown/ )

 

[CRLLS]

You probably want GFCI outlets in a kitchen anyway. Relatively easy to replace an existing outlet.

Alternatively, you can get a GFCI breaker and all the outlets on that circuit will be protected. That can be accomplished also by finding the 1st outlet in the circuit and wiring the rest in series with the GFCI outlet. If that 1st outlet is behind a refrigerator, it makes access difficult Usually there is more than 1 circuit in a kitchen requiring more than 1 GFCI if that is your desire.

 

[RobbieB]

I would just gut and reno the entire kitchen.
We did that because the microwave handle broke.
Hire professionals.
Blow that dough. ( https://www.financialsamurai.com/the-fear-of-running-out-of-money-in-retirement-is-overblown/ )

Hehe, microwave handle eh? Haha!

We did it because one of the wall cabinets (full of dishes) fell off the wall with a mighty crash not 5 feet from where my wife was standing.

Seventeen grand for the kitchen redo was cheap compared to what hospital time costs -

 

[omni550]

erkevin,

Another thought. Is it possible to take the countertop to a professional shop and have them do the cuts? If so, a quick call would get you an idea of the price.

omni

 

[erkevin]

The counters are expoxied-in and weigh a ton. I could have a pro come in and do it, but I kind of want the challenge. Yes, the house does need to upgrade to GFCI. For now, Home Depot has a portable GFCI that will get me through the weekend (I am on a timetable). I am going to do it wet to save on the dust (as well as good respirators)

 

[homestead]

Be careful vacuuming up close to the grinder. If you suck up sparks or red hot material they can lodge in the vac filter and catch the filter on fire.

 

[OldShooter]

One problem with cutting stone, particularly near the surface, is that the heat of cutting causes differential expansion in the stone and results in chips popping off on each side of the cut. (Yes, I know this from experience. )

I know nothing about "fake" stone countertop material but I would personally be very afraid of making a dry cut. If I was brave enough to attempt the cut at all I would use lots of water and go very slowly, stopping immediately if I saw any steam. A call to the manufacturer for advice might also be worthwhile.

 

[calmloki]

Was on the phone with an ex-neighbor mason a few days ago - he builds amazing things and makes many of his specialized tools. Currently replacing/rebuilding 100+ YO granite stairs for an Eastern Oregon courthouse and was telling me about having to do fluting and corbels on the rock and the tools he created - and more importantly for you, mentioned that the diamond blades went away too quickly and that he is using Remington Carbide blades to good effect. This material on various blades:
https://disstontools.com/product/7-remgrit-carbide-grit-circular-saw-blade-coarse/

Edit: when I've seen the mason cutting granite slabs or concrete slabs with a circular saw he made multiple shallow passes rater than trying to run a through-cut. Probably helps with the heating issue, but I'm not a mason and just report what I've seen.

 

[RobbieB]

The guys that did mine used a water system they lashed up themselves. Very low flow and they held it by hand, wasn't attached to the tool

 

[Bamaman]

I had to do the same thing with my granite. The stove was just a little wider than the hole provided. I had the granite guys come in to work on my sink anyway, and they did the cut.

It's not rocket science to use a good quality grinder with a good brand of diamond blade. I use them all the time when cutting porcelain tiles when rehabbing bathrooms.

All the methods you've noted are solid. You have it down pat.

Forget about the GFCI circuit. In a kitchen, the chances are that the first socket in the circuit is already a GFCI unit. Unless working close to water, it's not an issue.

 

[pb4uski]

I'd hire pro for something like that.

 

[GalaxyBoy]

Seems like it would be cheaper to replace the nearest outlet with GFCI instead of buying a GFCI extension cord, or better yet, the first outlet on the circuit so that all downstream outlets are protected. Then again, you can use the cord for other purposes.

 

[HI Bill]

I would splurge on a wet saw such as the Dewalt DWC860W 4-3/8-Inch Wet/Dry Masonry Saw ($179 on Amazon with a diamond blade). I would also get a GFCI extension cord/adapter. Maybe cost you $200 total, and then use a wet-dry vac to keep it somewhat tidy. I would not cut dry.

Here's one tip from the www:

How to Cut Silestone Countertops

1. Attach a 4 1/2-inch diamond cutting wheel to the arbor of a 4 1/2-inch angle grinder. ...
2. Fill a 1-gallon plastic container. ...
3. Cover the area you need to cut with masking tape. ...
4. Pour water on the marked pencil line. ...
5. Move along the cut -- cutting the line 1/32 to 1/16 inch deep with each pass.

 

[RobbieB]

Good luck!

I would hire a pro too. What's the cost gonna be if you really screw up?

And your "dry cut because no GFCI" plan indicates you don't know what you're doing.

 

[Koolau]

No expert here, but keep in mind that some granite counter tops contain (very) significant levels of radioactive materials. It would be rare for this level of radioactivity to be dangerous to inhabitants. However, cutting the material could well spread particles which could later be inhaled. I'm telling you way more than I know, but my suggestion would be to investigate safety precautions which go beyond ground fault detection (and even your very wise use of respiratory protection.) Best luck and YMMV.

 

[davebarnes]

No expert here, but keep in mind that some granite counter tops contain (very) significant levels of radioactive materials.

Very true. You are not an expert.
The OP is planning to cut a synthetic quartz countertop.

 

[gerntz]

Actually Silestone. Here is my plan- I welcome comments.
I have to enlarge an existing cut-out for a new range install. Definitely has to be wider (2 cuts), but may also need to be deeper (3rd cut). I am going to use an angle grinder with a diamond blade. I am doing this as a dry cut, as there are no GFCI outlets nearby. As I cut, my wife will hold a vacuum hose near the rear of the blade to catch as much dust as possible. We are going to put up plastic in order to contain as much dust as possible also. We will have P100 masks on and eye goggles. I will do a shallow cut first as it will act as a guide for the complete cut. Cuts will be marked on painter's tape to protect from chips, etc. Fortunately, the rangetop has lips (overhang) so I do not have to be pretty or perfect in my cuts.
What have I forgotten?

The professionals. I'm not risking the granite. Then I'm not a craftsman of any kind.

 

[Telly]

I renovated our kitchen about ten years ago. We used high-end Silestone. Silestone was only installed through a Silestone-approved installer. Cutouts were done by the installer outside, using dimensions from our new sink and cooktop installation instructions. They used the method that HNL Bill listed. The water was in a large squirt bottle. The cutting operation was similar to me cutting brick or concrete with a masonry diamond circular saw blade. Shallow, then deeper and deeper each pass. Does not take an excessive amount of water, I'm assuming cutting Silestone uses the slurry method just like masonry.

The cooktop cutout, initially looking OK, was really a bit akilter, so I needed to trim a bit on two diagonally opposite sides. I used a carbide drum in a drill, was slow going but OK. Would not want to expand two complete sides that way

A suggestion... Our cooktop (and I assume most would be the same) on a ~25" deep countertop, does not leave a whole lot of "meat" left in front of and behind the cutout. The front countertop edge is reinforced by the doubling layer to get a thicker exposed edge, but the rear does not. Even though the cooktop's surface will hide the cuts, I would not "overcut" the corners of the cutout. "Overcut" meaning overshooting the end of the cut on purpose to get the blade to drop through, due to circular blade vs. a vertical cut face desired. Could cut the last bit with a rod blade in a hacksaw.

A true work of art would be to stop a little short on the cut, and use a small diameter carbide drum bit in a drill to give a radiused fillet. Not much chance of a crack ever propagating from that! But would need to check guts of cooktop to verify clearance in corners.


Portable GFCI - I made one with a 4" steel duplex box, GFCI outlet, plastic outlet face plate, cord clamp for 1/2" knockout on box, and a 3-wire cord with molded-on male plug. Cord like that readily available, like cut off unneeded end of an old computer power supply cord, cord off an appliance, cheap short extension cord, etc. etc.