You should never use sand in a blast cabinet. First, when sand hits something hard it fractures and the resulting crystalline silica can give you silicosis. Read this for an overview: https://www.osha.gov/OshDoc/data_Gen...-factsheet.pdf. Second, sand is rounded and makes a poor media. Better yet is coal slag. It is sharp, doesn't give off silica, and is relatively inexpensive. It goes by several names, but one is Black Diamond and I get mine at Tractor Supply.

But, I do use some glass bead for things that are softer than steel, like aluminum. And, I use walnut hulls on aluminum as well.

 

Yeah I've seen Black Beauty, I'm thinking that's the same thing.

 

Yes, I've seen it as Black Beauty as well. Goes for about $8 for 50 lbs and does a good job.