Hi, Paul,
I hope not to hi-jack your thread but, I have a question along the same lines.
Why sand between coats of polyurethane at all?
I seem to have good success with a wonderful finish by applying the coats of
polyurethane, allowing it to absorb into the wood and get fiarly well dry, and then
applying additional coats. After about 3 or 4 coats, I let that dry over-night and
apply the final coat.
The instructions on the can never made sense to me that it can be re-applied
WITHIN 2 HOURS but, if you don't re-apply that quickly let it dry for 72 hours.
That doesn't sound like quick drying to me.
God Bless! Spirithorse