> Ray's page is what got me interested in the process. But in all the other
> kayak pages I have never heard of anyone else using it. I suspect that the
> cost of the equipment might make it cost prohibitive if you are making
> only one or two boats.

The cost of the vacuum pump is a lot, but in the grand scheme of things, I don't think it is "prohibitive." (It's cheaper than a decent table saw, for instance.) I bought a Gast pump capable of pulling >20"Hg last year on Ebay, thinking it would be useful both for FRP projects and for veneering. I have yet to set it up with pipe fittings, a regulator valve, etc--and I haven't even spent enough time yet to figure out how to attach an electric cord to the motor. So I can't offer much expertise.

As for prices, I found a couple places on the web that had complete kits (motor, pump, fittings, valves, vacuum bag, bleeder ply, etc.) for around $200 or $300 dollars. I can't remember now which places sold them, but it might have been Aerospace Composites and Aircraft Spruce.

I also bought a ton of books from Amazon/Barnes & Noble about using composites, and they generally had a discussion of the vacuum bagging process, but not in the boatbuilding context. West Systems has a pamphlet on vacuum bagging, too, and it does deal with boats.

I think the way that vacuum bagging maximizes the fiber-to-resin ratio is by pulling everything in the bag tight against the mold (female or male). There is no room between the fiberglass/kevlar/carbon/etc. cloth and the mold, so any resin must be filling the weave or above the weave. If it is above the weave, it is soaked up by the bleeder ply, which has been pulled snug against the cloth. I may be totally talking out of may @$$, though, so maybe someone else can enlighten us.

--Will