Best blasting media for aluminum?
 

I have quite a few aluminum pieces that I'm looking to clean up before install (engine block / pan, accessory brackets, control arms, etc..) and trying to find something that won't profile the metal too much. Today I tried some 80 grit black diamond, but even at low pressure I feel it's too harsh. Unfortunately it's the least aggressive media I've been able to find locally. Anyone else have any success blasting aluminum?

I've always had great results with glass bead. It leaves a frosted look to the aluminum parts.

That's good to hear. I found a place across town that has both glass bead and walnut shells. I plan on picking them up and doing some testing.

I tried the walnut first and found it didn't work well. The pieces bounce off of the material and don't have the tooth I was looking for. When I switched to glass, it was smooth sailing.

I use the finest grit sand they sell and it looks shiney.

I use Glass beads.Really give's a nice finish w/o the use of paint.When you come to pick up your subframe bring a pc. and I give you a sample.:thumbsup: Scott

What grit glass are you guys using? Turns out that the finest they have is 80 grit.
Which brings up another question... is it the grit or the hardness of the blasting medium that I should be most worried about? I can order in white aluminum oxide down to 220 grit.

Scott, Thanks for the offer. If I haven't found something that works before then I'll take you up on that. I have a lower A-arm that has a small section I tested today. It'd be interesting to see a comparison on the same material.

Rhino, check local Harbor Freight or Northern Tool, usually they have blasting media, although HF has ridiculous prices on media compared to the rest of their products,it might help you in a pinch.

I would try walnut shells or plastic, anything coarse will leave surface finish prone to get dirty quick and PITA to keep clean