After reading all of the suggestions, I like this one best. I would make only two changes.

1) Either do away with minicell padding, or replace w/ thin (1/4") neoprene from old wetsuit. Drill 3/4" ventilation holes (or punch them w/ punch make from emt conduit pipe) to keep from sweating between backrest and skin.

2) Use contact cement to laminate two bucket walls for thickness if extra strength is req'd.

> I use a section cut from a 5 gal. plastic bucket,it has the rigth
> cuvature.Aproximatly 6-8 inches wide.Two bolts hold from the sides
> of the boat. It is lined with minicell foam carved to fit the contour
> of the back