In encaustic workshops I have taken, the instructor said only to use natural
bristle brushes--not synthetic. We always had a can of (hot) melted paraffin
on hand and would dip our brushes in it. This would remove most of the
beeswax/damar/paint mixture from the bristles.
What are you using to fuse layers of encaustic? Propane torches? A griddle?
Encaustic is fun, but the fumes from the beeswax, oil paint, torches, paint
thinner, etc. are so dangerous. What do you do about that?