Grinding aluminum, what wheel?

[cgallery]

Need to grind some aluminum. My angle grinder came w/ a sort of general purpose wheel that loads with aluminum REAL FAST. Do places like Home Depot or Lowes sell wheels that are better for aluminum? I've head of people using cubic zirconium, but that sounds like it might be kinda pricey.

TIA!

[Tom Slick]

not only does a regular grinding wheel load up fast but it can explode when used with aluminum!

the type of disc that has flaps of sand paper looking material laid down on them, called a flap disc.




you can find them at home depot/lowes/ace hardware.

60 to 80 grit should work well for you.

[WayneJ]

HF also sells those flap discs
Wayne

[LCHIEN]

I have been told that using the regular grinding wheels with aluminum is a strict no-no. They can explode or fly apart when the aluminum loads it up.

[cgallery]

Thanks everyone for the warnings of the dangers of aluminum and grinding wheels! I was at the BORG today and picked-up the appropriate wheel.

[sacherjj]

The worst account that I heard about was posted somewhere on the web with pictures. The dad ground a bunch of aluminum on hit normal 6" or 8" grinder. Later his son cam in an needed to grind steel. This ignited the aluminum dust (basically thermite) and gave him 2nd degree burns about the face, hands, etc.

[LCHIEN]

http://www.ind.carborundumabrasives.com/Media/Documents/S0000000000000001045/Safety%20-%20Bench%20Grinding%20Wheels.pdf

[Stytooner]

I generally cut, sand or route aluminum. No grinding. This keeps the aluminum dust out of my steel dust and vice versa. I don't care to be building dormant but potential flammables in the shop.
I do sand some steel too, but make sure I clean up between the two.

[leehljp]

While an over simplification, thermite is basically steel/iron and aluminum powder.

One of the factors that the twin towers collapsed was the fact that the initial impact dislodged most of the insulation on the floors of the impact; the aluminum of the plane meshed with the some of the steel beams and girders, the high temps of the fuels helped in the reaction but once the aluminum and steel combination started burning . . .

[cgallery]

I'm having trouble finding the appropriate wheel that will fit my 4" RA grinder. The ones at Home Depot are 4-1/2" and have a different hub.

I've tried finding the correct ones at McMaster but their online catalog doesn't specify which are safe for aluminum. We order stuff from them pretty routinely, so does anyone know a McMaster part # for a 4" aluminum-safe grinding wheel?

Or any other local sources?

TIA,
Phil

[Tom Slick]

try your local welding supply if you want to buy local. your options are limited with a 4" disc. any of the flap disc style are safe for aluminum because they don't load up. it's the hard grinding wheel style that are dangerous.

I would use something similar to a McMaster p/n 4745A42.

[scorrpio]

Care to describe the project in more detail? I find aluminum is far easier to work using carbide tools. I had great results with a router. You just need to take lighter passes.