OK, I got out the 60 grit (HD didn't have any 40) and took it down to
the wood. Don't know whether it was another few days of curing, or the
coarser grit, but it went much quicker and smoother than when I used
the 220. No plastic melting, etc.

So I need to do passes with 150 and 220, but does anybody have any
thoughts on wood filler? Should I just assume the deep grain pits are
full of Polycrylic and don't worry about it? Didn't worry about it
with the Polycrylic and it seemed OK.

Now I just gotta find the Varathane DWF Floors. HD didn't have it, and
neither did the local Ace hardware (except one 4oz can of gloss). They
had all kinds of Varathane products but not the DWF WB.

Gary