View Full Version : how best to cut cultured marble?

Rockstar Dave
08-22-2006, 06:13 PM
Hello all,

I have a 25" wide cultured marble sink that has to fit in a 24" niche. I've had some people tell me cut it with a circular saw with a fine carbide blade, others say use a handsaw (hacksaw?) for more control, and another said to use a belt sander. Anyone have any experience or preferences for one way or another? Thanks so much for your help.

Dave in PA

08-22-2006, 06:38 PM
You won't be able to cut it straight with a hacksaw. Do you have a router?

Will the edges be covered with anything? THere is often a lip on the edges to help keep water from rolling off.

Strap a straightedge to the bottom of the thing and use your circular saw.

If you have a belt sander, you could use that.

Do a search here...someone did this a few months ago (search is in the blue bar near the top).

08-22-2006, 08:59 PM
I would try a circ. saw with a diamond blade. You may need to cut it wet, but I'm not sure how to do that. I'm sure many others here can help you.

08-23-2006, 05:57 AM
Almsot any saw will cut it. Your problem is really how to make a straight cut. I use a SawZall with a fine blade and proceed slowly. A belt sander afterwards will smooth the edge. An "abrasive" wheel such as a diamond blade will melt the material, and clog the blade.

Designers Marble in Woodinville WA


Rockstar Dave
08-23-2006, 06:10 AM
Hi guys, thanks for the quick replies & helpful advice.

In reply to some of your questions -

the sink will butt up against walls on either side. This is a really small bathroom. The vanity/sink is in a sort of niche that is just under 24" wide. (I bought a 24" vanity and had to take it apart and reassemble it in the niche, because it wouldn't fit through the space assembled!). The walls are moisture-resistant sheetrock with the good moisture-resistant primer and paint.

I don't own a router, but I know someone that does. I like the sawzall idea, gotta go pick up some fine blades.

Thanks again!


08-23-2006, 07:07 AM

You may want to make a template first. It is often necessary to take a little off each side to get a good fit. As you found with the vanity, everything that should be is not always square.

I would use a circular saw or a router, if using a circular saw, tape the cut line first. Use a straight edge to run the saw or router along. Use a mask, and do the cut outside.

If you use a router, it is safest to use a bit with a shaft larger than 1/4 inch.


Rockstar Dave
08-23-2006, 07:27 AM
Template sounds like a good idea. How would you do the straightedge? Maybe clamp a piece of wood to the sink for the saw to run next to?

Thanks again,


08-23-2006, 09:14 AM
A good straight board works fine, offset to bring the blade where you want it.

The trick is to get the fit where a small caulk line will fill the gap equally all around.


08-23-2006, 07:31 PM
An "abrasive" wheel such as a diamond blade will melt the material, and clog the blade.

Is this true? A diamond blade will melt cultured marble?:confused:

08-24-2006, 02:03 PM
I would use a high toothed carbide, but see what some of the other guys say. It is resin so heat will melt it.

Don't forget the finished surface is mm thin.


08-24-2006, 02:08 PM
A diamond blade like used for tilework, is basically microscopic diamond dust. It cuts by grinding more than what we think of cutting. It would quickly clog up with a thermoplastic material. A carbide wood blade stays sharper longer, and would make a clean cut on cultured marble. A new good quality wood blade would do it too, but might get dulled some.

08-25-2006, 05:52 AM
IF the 24" cabinet would not go into the space assembled, then you also have to cut the top slightly undersized so it can be tilted/twisted in.