About 3 days ago I used a 1/4 sheet sander to flatten some cabinet doors
after applying sanding sealer. Last night I emptied the dust collector bag
into the empty trash can, about half an hour latter I smelt burning and saw
that the small heap of wood dust I had emptied had started to smolder with a
very heavy smoke. Attempts to grind out the embers failed and I ended up
emptying the dust outside.

I mention this on this newsgroup as this is the first time I have had this
sort of problem and I have been an active woodworker for almost 40 years. I
am assuming the problem was due to the sanding sealer dust, though it was a
water based product I guess that the residual chemicals reacted when exposed
to air. The wood was hard maple and the amount of dust was about 1/4 cup,
the container was a plastic box which contained no other material.

A warning to the unwary.

Any comments would be appreciated.

Bernard R