Thumbs wrote:
I'm re-flooring our basement with hardwood. It's about 600 sq feet, raised
with an old glued on carpet. I pulled up the all the carpet and a thin
layer of under carpet remains stuck to the half inch plywood. Removing
this layer looks to be like quite a painful task (I gave it a small shot
with a scraper). I'm thinking - forget it - I'll just lay down the
receiving paper directly on this under-carpet, then harness down my
hardwood from there. Should anyone talk me out of this? Do I have to
painstakingly remove this thin layer of under-carpet? I figure it's no
thicker than vapor retarder material that they sell to go underneath
hardwood floors... anybody?

A floor sander or polisher with a coarse pad should take off the
remaining foam .