strange fruit

Posted by Tom S on Feb 13, 2007

All,

After a couple weeks of not making much progress (but I wasn't just eatin' cheetos and watching the tube; there was a trip to Corpus Christi thrown in there - whooping cranes, white-tailed hawks, black-bellied whistling ducks!) I got around to making the end pours on my CH18 last night. I'd read a post on here some time ago from an engineer who had added ground up styrofoam to his end pour mixture to lighten it and that sounded like a good idea so that's what I did. About 50% by volume styrofoam that had been run through an old blender until it was roughly the size of lentils. There were a few fines and there were a few larger crumbs, but I tried to pick out any obviously larger pieces. Anyway, it seemed to work well enough, although the styrofoam is so light it wants to stick to everything due to static electricity and I'll be cleaning up stray bits for months. When I came in this morning, however, I found that the material had "risen" and overflowed the end pours like cake batter with too much baking soda. It's a real mess, as you can see in the accompanying photos (the two at the top of the page are the ones from today's incident; the others were posted weeks ago). Since taking the photos I've been able to take a reciprocating saw and carefully slice off the largest portion of the excess but I've still got a couple hours of cleanup work with my Dremel, scrapers and sander to restore the outside of the hull to any semblance of its prior state.

I just wanted to make everyone aware of this phenomenon. I'm pleased with the material - the piece I lopped off is hard but very light - so I think the concept is a good one for keeping end pours light while accomplishing the original purpose of strengthening the ends and tieing them together. But something in the mix (heat from the epoxy?) caused the mixture to swell and overflow the cavity and the resulting mess is more than I bargained for. If any of you know what I did wrong, I'd be pleased to hear it.

Tom in Cape Charles


http://www.flickr.com/photos/77032278@N00/?saved=1

Replies: