These are the sanding blocks I fabricated for the sanding work I did on the roof. I have power sanders, of course, but rarely used them for two reasons - 1) The blocks allow for even sanding with no dips and swells, and 2) the blocks don't get dust all over my shop like a power sander does, even when used with vacuum system. Oh, and 3) the use of the blocks provide a nice upper body workout.(winking smile emoji here)