Chuck, my foam was imperfect. In order to blend in with society I have to make mistakes so nobody realizes I'm actually a terminator. So the foam stuck up around the edges and was in general a little too thick. With it bonded down, I was able to sand it and get it pretty good:
Note my sanding block is actually a piece of Hobie skin from the failed hull. It is flexible so I can follow the contour. It isn't perfect but I think good enough. I will probably flox a couple of edge gaps that are there, and whip some layers of glass on top. Perfect is the enemy of good enough.
At Sikorsky we used to do like you say - except everything was carbon prepreg, we had CNC machined molds, and CNC machined foam or Nomex core. We would pull the prepreg carbon out of the freezer, let it thaw a little, place parts in the mold, vacuum bag it, then stick it in the pressurized autoclave.
If I was going to vacuum bag glass I'd break down and buy some peel ply. That does a couple of things -
1) leaves the finish with a textured surface, suitable for bonding to
2) soaks up the excess resin
That silver AC tape is old but works good enough. We had one leak on the tape but just kept adding more until it went away.
Clever idea, making an inverse air compressor!
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Bryan in Poplar Grove, IL
Supercat 17, unknown year. Future project
Hobie 16, 1977 - died a spectacular death
https://youtu.be/Y7O22bp2MVA
Hobie 16, 1978 - current boat
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