Made a quick test video about angle grinder diamond metal blade.

[Tuomas]

As the title says.

I made a short test / comparison about the angle grinder diamond metal cutting blade.

It works, but personally i don't like it, if used free handed.
With stand it could be more useful, if you don't mind that it cuts much slower than abrasives.

Nice thing was that it actually performs quite similarly when used with 1250w Metabo angle grinder,
and with 700w Einhell circular saw. Circular saw runs less than half of the rpm of Metabo.


When using abrasives on that same speed, then its not so much slower at all.

Good things are that it makes less dust and sparks.

[Crusty]

I agree that abrasive cutoff wheels are the best choice for cutting metals. I prefer the Makita super thin wheels because they cut through steel quickly.

One application though in which the diamond wheels (and blades) shine is cutting rock. I have a Dewalt diamond rock cutting blade and it's just short of amazing how fast it cuts through granite countertop and it leaves a nice edge.

[Tuomas]

I agree that abrasive cutoff wheels are the best choice for cutting metals. I prefer the Makita super thin wheels because they cut through steel quickly.

One application though in which the diamond wheels (and blades) shine is cutting rock. I have a Dewalt diamond rock cutting blade and it's just short of amazing how fast it cuts through granite countertop and it leaves a nice edge.

Yeah. That's why i was amazed that this diamond blade didn't cut stone or tile nearly at all.

I had two of them and both are somewhat ruined.
First with the stone, second with stainless 316.

That's why i choosed to use Bosch multiconstruction wheels, because it also cuts stone. My intention was to compare that too.. but diamond blade lost all of its diamonds.

Cubitron 2 was choosed because it performs well with stainless 316, diamond blade overheated again.

So, i decided to leave those parts from the video. Allthougt, diamond blade was made for steel only.

[Ralphxyz]

Now you have to look at some carbide metal cutting wheels. I know they come for a circular saw don't know about an angle grinder.

[hemmjo]

I have been using LENOX METALMAX, abrasive steel wheels on my 4 1/2" angle grinder. For some situations, they work very well. As mentioned they make less dust and sparks on metal. I have used them for brick, block, mortar, stone, steel roofing, and some 1/4" steel bar stock. Of course there are lots of different kinds of stone, I have not has occasion to try granite.

It is a little slower that a good abrasive wheel for heavy cutting. It is unbeatable in a harsh environment where the smallest miss alignment will shatter a standard abrasive wheel. I use them on my DeWalt rechargeable 8,000 rpm, as well as my OLD craftsman corded 13,000 RPM. Of course it cuts faster on the high speed grinder but the durability for out of position work with the portable wonderful.

As will all tools, every feature has a trade off. I still carry both kinds with me on a job, but I use the Lennox most of the time.

[madokie]

yes the thin cutoff abrasive wheels do cut faster,but i do metal scraping in the USA,and i ,like some scrappers and plenty of other people have more time than money ,for me the diamond wheels are they way to go, no worries about wheels braking up and throwing pieces all over,,and u just get more cuts from the diamond wheel, however, i was using one to cut up some welded angle iron and channel and the diamond wheel binded up in the cut more than did the abrasive wheel,,just something to be aware of..these diamond wheel are now made in the USA,south korea,and china..dont know which is better..

[Ralphxyz]

On various metalworking forums I have seen warnings about using diamond on metals. Something about carbon on carbon gums up
so it was said to never touch diamond to metal, this was I "think" concerning grinding.

[jdurand]

Diamonds are carbon. Carbon burns when it gets hot. Steel will also absorb some amount of carbon.

[Ralphxyz]

jdurand, ??? so should you not cut/grind metal with diamond?

[jdurand]

You'll just wear the diamond down faster than you expected. Things like AO (aluminum oxide) are already oxidized and have nowhere else to go.

I seem to remember diamond is fine for LOW SPEED metal grinding where nothing gets hot, like knife sharpening.