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

Linseed oil is notorious for combustion, maybe you had some of that in there.

Any polymerization reaction is likely to be exothermic, and with the heat
contained as well as it is by fine dust or a tightly twisted rag, stuff can
happen. You're not safe because it's not linseed.

I'd let any finish cure well before sanding, even a "sanding sealer," which
is normally a thinned version of a finish.

"Gfretwell" wrote in message
...
Linseed oil is notorious for combustion, maybe you had some of that in
there.