New vacuum pump setup

[Mike Minto]

Was wanting to try vacuum chucking, so after thinking about it for a while (and reading that Larry Marley uses the same pump) I bought the 110 volt HF 2.5 cfm pump (in the store with a $74 online price match). I have a very simple setup - if anyone sees problems with it, please let me know, but all I am using is the pump, homemade chucks, a vacuum gauge (Northern) and a pressure relief valve (really not needed with this setup, as the pump bleeds air - and some oil, I think Mr Marley said, so the pump has to run continually - does the Gast version?). Have no worries - my gauge shows a whopping 28 on the vacuum scale with a very good seal at the headstock - if it is true, I for one am impressed.

[Richard Madison]

Mike, Hope you have a filter upstream of the pump intake to keep sawdust or whatever out of your pump.

[Mike Minto]

Actualy did at first, a Husky filter, but it won't stop leaking - must be a bad one - will be stopping back at the Depot tomorrow a.m. to return it. Can anyone recommend a good inline filter? thanks, mike

[Steve Schlumpf]

Mike - vacuum chuck systems are amazing when it comes to finishing off the bottom of a turning!

Your system really works well if it can pull 28 hg! That is impressive! The relief value plays an important part with your system - that is to regulate the amount of vacuum at the chuck. Don't know what size chucks you have - but with the same amount of hg - the pressure at the chuck goes up dramatically with increasing size. You can use the relief value to regulate the hg and prevent excessive pressure from destroying your turning. No set rules that I am aware of - but I usually run my system at 20 hg. So far it holds everything well and doesn't overtax the pump. Oh, I use a Gast 523 and it does run continuiously.

[Mike Minto]

Steve, thanks for the info - I believe I'll keep and experiment with that relief valve, haha. I have only made a couple of PVC chucks using ash tapped with the Beall tool, one about 3" and the other about 1 1/2". Sealed with RTV and silicone caulk. Re the gasket, I bought some thin (around 1/8") closed cell material at Wallyworld. I'm currently turning an Eastern Cedar crotch, will finish on the vacuum and show pics/tell stories when completed. Again, can anyone recommend a good air filter for my system? thanks, mike

[Steve Schlumpf]

Mike - without knowing what size diameter of vacuum hose you are using - it's hard to recommend exact filters. Surplus Center, online, is where I bought mine but depending on your setup, may be able to get by with an in-line fuel filter. The filter I am talking about uses a paper filter, has a 1/4" inlet/outlet and usually is for off-road vehicles, 4-wheelers, etc. I picked mine up at WalMart in the automotive dept.

[Mike Minto]

Ah, thanks again. My vac hose is 3/8" - I'll look at WM soon. Mike

[Steve Schlumpf]

Mike - just to show what I used for intake air filter: http://www.surpluscenter.com/item.asp?UID=2009031516480984&item=4-1565&catname=air

I used the inline fuel filter to filter the air at the relief valve.