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by almost_usual 2154 days ago
They don’t mention what kind of blade was used in the experiment? Interested if it was a diamond blade or a conventional blade.

When pausing the video it looks like a conventional cut off wheel.

1 comments

It's an alumina fiber reinforced blade, same ceramic as in the material. It's the most common grinding wheel material.

Diamond blades are not especially good at cutting. They only used when absolutely necessary, ie when your material is extremely hard. Diamond sublimates at low temperatures, it dulls quickly because of the fracture planes, and it's so weak and brittle that only tiny grains can survive being used to cut.

The alumina spheres they use are softer than diamond, but handle the cutting environment much better. Zirconia wheels handle cutting even better (up to 10x better) than alumina, but its softer. No idea what would be ideal.

Loading a power washer with some expensive abrasives would still cut this fairly quickly, and a thermic torch would cut it very quickly. Kind of requires you to not care about what's actually on the inside, though.

I use diamond metal blades because I don’t want my blade turning into shrapnel.