vacuum pump requirements

[Charles Bouchelle]

What are the specs I should be looking for in a vacuum pump for making a vacuum chuck?

[Gary Conklin]

Charles, can you expand upon what it is you are looking for? Are you looking for vacuum? Fit? Not sure what it is you need....:confused:

[Charles Bouchelle]

I am thinking about making a vacuum chuck set up,but I don't know what the specs should be when looking for a used pump on ebay.

[Ryan Baker]

Something like 2.5-4 CFM, 25-30 in Hg should be adequate. If you can find a used Gast for a good price, that would be ideal.

[Steve Schlumpf]

In addition to what Ryan recommended - I would also suggest a rotary vane style of pump simply because it is supposed to be quieter.

Good luck with your build! If you have any questions - ask - as there are a number of folks who have built their own systems!

[Don Geiger]

You need a pump with at least 4.5 CFM flow at atmospheric pressure. The 1/4 h.p. ones sold in popular woodturning catalogs just meet this requirement. The purpose for the flow rate requirement is because sufficient flow is needed to overcome losses that will exist in leaks around fittings, gaskets etc. and there is almost always flow through the wood since wood is permeable.

Carbon vane pumps are well suited for our applications in wood turning. If you find a used one that runs, the vanes are easily replaced and are failry inexpensive to buy.

I opted for the 3/4 h.p. Gast because it has over 8 CFM of flow. I've acutally found situations where I needed two pumps hooked to the same line in parallel to overcome the flow through very permeable woods.

Don Geiger

[Doug Wolf]

I'm not a big fan of Harbor Freight but when a friend couldn't find a surplus GAST pump like I used on my Vacuum system he bought a http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=98076 and it works as good as my GAST, plus it's 120 Volt instead of 240.


Here's a picture of my friends system. He's getting 24" Hg at 5000 ft elevation.

[Gary Conklin]

The Gast 523 that I use has served me well so far. It is also the one that I commonly see used. Though Tom is selling another model that is being reviewed well.