: Some hardware/machinery stores sell a set of 3 toothtype brushes
: (for abt $5), where each brush has a different bristle type:
: nylon, brass and stainless steel. The stainless steel bristles
: are really fine and will scratch out a fair proportion of the
: tiny holes with the white dust.

: In my case however, I have a bad habit of pounding the brush into
: the resin at difficult areas and therebye foaming the resin
: which leave hundreds of miniscule bubbles that pinhole on
: sanding. The effective technique for those (like hundreds and
: hundreds and hundreds of them) was the brush mentioned above and
: to tape a syringe needle onto the end of an airhose and the
: finely directed air just blows the holes clear - the fine holes
: require attention one by one, but it works. I've used both an
: air compressor and a salvaged fridge compressor for the air with
: equally effective results.

Unless the air compressor is truely oil free I'd recommend to not use it, doesn't take much oil to make an awful mess with epoxy or for that matter varnish.

Bill H.