Grinding wheel for cutting concrete

[dwasifar]

I need to cut a short drainage groove in a concrete curb. Angle grinder seems like the logical tool.

But when I search for concrete grinding wheels for an angle grinder, I only find cup wheels that are designed for surface grinding, and nothing that's intended for cutting.

Any reason I can't just use ordinary metal grinding wheels, if I don't mind using up the wheels? The cut only needs to be about 3/4" wide by a foot long.

EDIT: Found a couple of masonry cutting wheels with another search, but I'm still curious if I can grind with the wheels I have.

 

[Dave455]

You need a cutting disc, not a grinding disc.

Search on “masonry cutting disc” or “stone cutting disc” and you should find what you need.

In practice, you have a choice between conventional discs


Or diamond discs


Even though I cut masonry or concrete infrequently, I much prefer the diamond discs to use, even though they are costly.

I have no idea what happens when you try and cut concrete with a metal cutting disc, but my gut feeling is that it’s not going to work well, if at all.

Given that the main risk is the disc shattering, and the cost of the correct disc is minimal, I see no reason not to use the correct tool!

Unless you need a less common size, there should be no problem getting hold of these.

 

[neophyte]

Abrasive wheels for cutting stone are usually made with Silicon Carbide grit, not the Aluminum Oxide usually used for cutting and grinding disks for steel.
There are sometimes combination wheels that contain both Silicon Carbide and Aluminum Oxide for use on both concrete/stone and steel.

Nowadays diamond grit wheels are mostly used for concrete.
A steel wheel should be safer, since it is unlikely to fracture compared to an abrasive disk, and the diamond grit should cut longer and better, while maintaining wheel diameter.
There are also diamond Combo wheels meant for cutting everything from steel to masonry.

 

[no704]

HF has the diamond wheels pretty cheep. I have a 4.5” and a 9”. Cut a channel about 5’ long with the 9” and a HF grinder with a slow water trickle. Made a mess but worked great.

 

[Bert_]

The 4 1/2" diamond cutting wheels are cheap and very handy. I got one a few years ago and find I use it semi often.

 

[DHCrocks]

Definitely get a diamond wheel. I used the Dewalt 4-1/2" one on my grinder and it cut so much cleaner and faster then the abrasive type. They also last longer and do not wear away and get smaller in diameter.

 

[geojag]

Diamond all the way! It is dirty work, a shop vac can make it less dirty.

 

[dwasifar]

Thanks guys.

 

[jonesg]

concrete needs diamonds, hose it down and keep it wet.
If you don't keep it wet you'll needs new bearings for the grinder, I wouldn't use my milwaukee, buy a cheap wen or ryobi.