> A message I read here recently reminded me: Has anyone had experience
> fabricating a custom form fitting seat using aerosol urethane foam in a
> plastic bag in a rough form and then sitting in the whole mess like a
> brooding hen, until it congeals about your gluts producing a perfect fit
> for your tush? I'm told that endurance car racers employ this method to
> combat 'lead butt' on their epic drives, and was reminded of the process
> when some aquarium hardware came delivered intact utilizing the same
> process. Anyone out there actually know how to do this? I await your reply
> of Sage of the Seat.

The problem with using the expanding foam directly is that it soaks up moisture, and it is not very durable. You can improve on the durability by covering the mold with a few layers of fiberglass cloth and epoxy resin, but the more layers of glass that you put on the tighter the fit is going to be. You could enlarge the seat area by removing an 1/8th of an inch or so of the foam to compensate.

Try to get in touch with Paul Stomski. He built a triple with cutouts where the cockpits should be so that the kayak could be used as an open cockpit design. He molded his butt in foam, using the method you've described, and, as I understand, sliced the mold into slabs, each 2 inches thick) with the intention of using those slabs as models for similar pieces cut from 2 inch thick sheets of closed cell foam (a generic equivalent to Minicell foam).

Here is a link to his post on this BBS on the launching of his boat. If you follow the links on that post you can get to his family home page and see some pictures. At the time he took the pictures he was using a different seat, though. His e-mail address is on the posting, too. Hopefully it still works, as it is about a year old.

http://www.guillemot-kayaks.com/KBbbsOld/3827.shtml

By the way, if you contact him, say `hi' for us.

Hope this helps.

Paul G. Jacobson