SPECTANGULAR!

I have a 3/4HP 90VDC motor and variable controller for it on the shelf.

Now I know what I want to build with it.
:-)

I will make mine so the entire thing tilts over sideways 90 degrees so it acts like a little edge sander - very nice when you can see the curve the small wheel is putting in things.

I really like your reversible platen/roller assembly. Great idea.

Marksburg:
I like the idea of timing belt tensioer pulleys - $20 or les new on Ebay.
:-)