Thank you all, I'm glad you like 'em.
Wayne, I ain't buying 'em, but I wish I could sell some of them
Bob, I made that vent system with some old swimming pool hoses and a shop vac.
I put all those hoses together (about 12') I put my shop vac outside and ran the cord and hose through an old dryer vent down into my basement. I rigged the hose up so it's positioned just below my knees while i'm sitting on a bucket. While I abrade, I be sure to abrade right in front of the hose. It pulles all the dust outside and even while I'm knapping, all the tiny dust particles are pulled down and away from my face by the slight suction the hose creates. It may not be perfect, but it's enough to make me feel better about things.
The key is...get the vac outside. That way, you don't have to hear it and it blows it's exaust outside. I reckon those silica dust particles are so small the filter system on a shop vac won't catch it all.