I also wear goggles and a face mask when I sand the cured mixture, because I don't want to breathe in any of the dust or get any of it into my eyes.
True that.A mask or respirator is actually a good idea for just about any sanding -- easier on the lungs if you don't inhale all that stuff.
-Kevin
Avoid microballons.
Use corn starch,it gives the same effect.
It's cheaper,safer, and easier to sand.
What are micro balloons?:shock: