Some time ago, I built a vacuum pump reservoir using the design and parts for the Vacuum Press at http://www.veneersupplies.com/ . I had to make some changes to allow me to use 240v. It was pretty good, but it would only hold about 17" Hg and it would recycle about every 5 minutes. ie a lot of leaks. It should be able to hold about 20"Hg for about 20 minutes at least.
While there is not a great need for a vacuum pump in the structural elements of the RV-10 (At least I hope not), I know it will come in handy for internal fitout. It is also great for getting bubbles out of pots of resin quickly. I use the Resin Infusion Catchpot from EasyComposites as a vacuum canister http://www.easycomposites.co.uk/products/vacuum-bagging/professional-resin-infusion-catch-pot-small.aspx when I am not doing infusion.
Well today I rebuilt it, adding new hose clamps to some reworked fittings. At the completion, I ran a vacuum test. With the new hoses, it held 21" of mercury for more than 1 hour with no sign of any drop in vacuum at all... Not much leakage which is great news. Big improvement.
