William R. Watt wrote:


still the vacuum on the suction side of a vacuum pump is not limited by
atmospheric pressure, even when connected to a vacuum bag set up for resin
curing. all it means is the pump is creating a vacuum greater than
atmospheric pressure and could be run at a lower speed. imagine a vacuum
pump strong enough to suck the resin, hull, and all right into the pump.
can't do that at atmopheric prssure.

That is why a lot of carbon spars are vacuum bagged inside a
pressureized and heated autoclave. Supprising how much you can squish a
carbon fiber layup at 100 psi. :-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com