2

I've picked up a 27"x27"x2" piece of marble countertop off the street. I'd like to clean it up and use it, but I'd also like to trim it down.

I don't mind doing it myself, but want to make sure I'm doing it right. I've seen posts saying a diamond blade for my circular saw will do the trick.

Am I correct that the following approaches are reasonable?

  1. Marble/masonry continuous rim diamond blade
  2. Multiple shallow passes
  3. A trickle of water from a hose (plus a GFCI outlet or extension cord)
  4. Protecting the surfaces of the slab from chip out with tape/foam board

Anything not right there? Anything I'm missing? Should I not attempt this?

Thanks!

  • Is your cut edge going to be visible/touch-able? Your ideas are sound (but for the fact that you'll do harm to your circular saw), but they won't get you a nice finished edge. – Aloysius Defenestrate Apr 20 at 18:53
  • what are you trying to cut? – DMoore Apr 20 at 19:01
  • @AloysiusDefenestrate do you mean harm to my saw or the blade? Should I scrounge up a cheap circular saw I don't mind sacrificing? (I expect to have to do a lot of polishing, fwiw.) – Tim Apr 20 at 19:10
  • 1
    @Tim -- the saw bearings suffer from both dry dust and slurry. They just aren't made for that kind of abuse. So, yes, I'd use a saw you aren't very fond of. (And the blade will probably survive a few more cuts like this, but they are consumables.) – Aloysius Defenestrate Apr 20 at 21:54
3

I have cut one inch granite and it went very well with one exception to your list. Make the cut in a single pass or you will have lines on the cut face. You can use a good circular saw because the small water flow will stop essentially all dust; there will be some water spray that contains fine particles but no problem. I have cut cinder block dry and that needed a "sacrificial " circular saw. Breakout was not a problem when going slow at the end of cut. What I did for water was use a gallon bottle with a 1/4 vinyl (aquarium) hose with a clamp or valve for control; then you can make the mess anywhere.It requires little water and it will run down the cut groove to the blade.

| improve this answer | |
  • I really suggest using duct tape in the middle of your cut line to reduce chipping and cracks on the top. – DMoore Apr 21 at 20:08
0

Marble is fairly easy, both to cut and to clean up after cutting (basically wet-sanding to remove marks) as it's a comparatively soft stone.

People do use water with saws not made to be used with water - I tend to think that's a bad idea, but you make your choices. Dust control is important for your breathing and your saw's bearings if using a power saw - depending on the cuts you actually need to make, a "grit-edge" hacksaw blade (manually driven) offers a low dust/noise/expense approach, or you work outside with a shop vac sucking up a much of the dust as possible, or you rent a wet saw for a few hours...

Personally, I have cut a lot of tiles (harder than marble) with a dry diamond blade in an angle grinder. My "nice" circular saw managed to die anyway (time for new brushes, OK! Wait, not the brushes - you want a new armature? Have you looked at the price of a whole new saw?) without being abused that way, (the angle grinder is still kicking) and my "new" circular saw came from Habitat for Humanity's "Re-Store" at a price were I'd not be so worried about replacing it if need be. You make your choices.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.