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Part 1
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From
James Bodnar's Combat Page (A vacuum system for RC planes/gliders) Continuous run vacuum pump for vacuum bagging.
My Dad found the perfect thing. It is a brass valve designed to bleed air out of natural gas lines for natural gas fireplaces. From there, it goes to clear 3/8 tubing to the vacuum bag. On the right side of the pump is the pressure side. The pump has oil in it. As it operates, a little of the oil flows out the pressure side. To fix this, that white bottle on the top of the pressure line is a reservoir. The bottom of the bottle (pointing upward in the picture) has holes drilled in it to let the air out. As the air and oil come out the tube into that bottle, the air slows down, the oil separates from the air and stays in the bottle as the air escapes out the bottom of the bottle. When you shut the pump off, the oil runs back into the pump. We've run this pump for as long as 48 straight hours with no problems. It did get slightly warm so we put a household fan on low pointed at it. The pump works great and is so quiet, you hardly know it's running. Now, you may ask, what am I vacuum bagging? My combat wings of course. I found a great place for inexpensive Fiberglass, Kevlar and Carbon Fiber fabric, West system epoxy, and peel ply. It is called the John R. Sweet Co. It is a nice sized business that got its start from supplying canoe and kayak enthusiast with composite materials. He now caters to Model enthusiasts too but at a signifigant savings compared to those other places. I'm using a two inch wide piece of 5.7 ounce Carbon Fiber on top and bottom of the thickest part of the wing, a layer of 1.7 ounce Kevlar from there forward then a piece of 2 ounce fiberglass over the top and bottom of the wing. Put on your epoxy, squeegee it off and put it in the bag for two days. Voila.
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Here's
what it is... It is the pump out of a small refrigerator. We had a fridge
that didn't have any freon in it so we disassembled it. The best place
to find a pump is at a appliance repair or appliance second hand shop.
If you get the whole fridge, please recycle the freon, don't just cut
the lines. I don't want to get skin cancer because you depleted the
ozone. Let me explain how this contraption works. It creates pressure
on one side and a vacuum at the other. On the left it the vacuum side.
We bought a brass fitting with a 1/4 compression ring on one side and
male 1/8 pipe threads on the other. It screws into a T-coupler. One
side goes to the fuel pump/vacuum gauge, the other goes towards the
vacuum bag itself. But, before it gets to the bag, we need a way to
regulate the pressure. Without it, the pump would draw max vacuum (around
27 inches of Mercury I think) and would crush the foam in the vacuum
bag. 
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