Air ereasing grit

[Chris333]

I'm buying one of these air powered grit blaster erasers. I want one to hit etched brass parts with to help paint stick better. I also would like to try it to clean up Shapeways FUD. So the question... What size grit should I be buying to try these things?

[C855B]

No firsthand experience here, but in my travels I keep running across recommendations about using baking soda for blast-etching models. FWIW.

[Kisatchie]

I've painted untreated brass with Scalecoat I paint with excellent results. I just sprayed the brass during the summer in my garage, closed all the doors, and let the heat cure the paint. It was bulletproof.


Hmm... there may be a
joke here somewhere,
but I'm not seein' it...

[wcfn100]

I use baking soda, but it's a mess.


Jason

[peteski]

I use baking soda, but it's a mess.


Jason

I use Badger version of a mini sandblasting gun with aluminum oxide abrasive. It creates a mess too.

Using any kind of powered abrasive through a mini sandblasting gun will create a mess.    That's why the real sandblasters are usually used inside a sandblasting booth.  I use mine in a large plastic storage container partially, covered with a heavy clear plastic film'

[wcfn100]

I have one of those clear inflatable round booths you stick your hands in.  I can't really see much after a couple minutes. 

Jason

[Chris333]

Well I guess baking soda is always handy.  I'll try some 240 grit as well.

[Scottl]

Smaller particles will erode less material based on their mass.  240 is probably a good start, but plastic like Shapeways FUD may need a finer grit like 400 or 1000.  Baking soda grains are also softer than alum oxide, so for a given size range it might be less aggressive.