wrote in message
ps.com...
I am reading info on rubbing finish. There is one thing that I don't
quite understand. The instruction indicates that we should thin the
finish, let it hardened, and then rub the finish. This instruction may
be good for other finishes; but I am wondering whether this is
practical for poly. According to the instruction, the poly finish must
be thick; otherwise, when I rub the finish, I may run the risk of
rubbing through the top coat of the poly and revealing the line between
the top coat and the second last coat. But if I thin the poly for the
top coat, I will get a thin coat and I will have a high risk of rubbing
through the top coat. Something is missing here, right?

Is the idea of "thinning the last coat" more appropriate for other
finishes that one coat can melt with the next coat, and multiple coats
can become one thick layer?

Thinning the last coat is different that building up multiple layers for
rubbing out. thinning the last coat (or every coat for that matter) helps
the finish to smooth out and reduces the size of brush marks, thus making
the entire polishing procedure go faster and easier.

Manufacturers are making finishes thicker to comply with VOC regulations as
there is less oil or carrier to flash off to the atmosphere. By adding a
little thinner back in, you can get a better finish, even though more coats
may be needed.

Let that poly cure for two weeks before rubbing it out.