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Greg McClurg
12-14-2020, 10:06 AM
I picked up a gast vacuum pump, model 0523-V191Q-G582DX, which I would like to use for a vacuum chuck system. I know nothing about vacuum pumps and my searches have not given me the information I'm looking for. Even checking the Gast website I can't find a manual on this specific pump. First is this an appropriate pump for a vacuum chuck system? If so can anyone share how to set this up and wire it correctly? Thanks for any assistance.

Greg

447072447071447073

Kevin Jenness
12-14-2020, 11:16 AM
447079447080That's an excellent pump for a vacuum chuck. Green is ground, the other two terminals are for the hot and neutral lines of a 110 volt circuit. A inline switch or switched outlet and a dump valve on the connection through the lathe spindle is all you really need (I am assuming the pump has an intake and exhaust filter not pictured, if not you should add them). A vacuum gauge is nice to have.

You can buy a chuck system such as Oneway or Holdfast offers or make your own. I used a Holdfast chuck adapter to connect through the spindle and made several chucks with a Beall spindle tap, wood and schedule 40 pipe.

Keith Outten
12-14-2020, 11:26 AM
https://www.joewoodworker.com/

Joe Woodworker's web site has kits you can purchased to make a really nice vac system. I purchased one of his kits for a small gast pump that I use in my shop. The Gast pump web site is where I got the information to convert my pressure pump to use as a vac pump, not every pump can be used for vac service.

John K Jordan
12-14-2020, 6:28 PM
https://www.joewoodworker.com/
Joe's web site has kits you can purchased to make a really nice vac system. I purchased one of his kits for a small gast pump that I use in my shop. The Gast pump web site is where I got the information to convert my pressure pump to use as a vac pump, not every pump can be used for vac service.

+1 on Joe's stuff and info. He is a helpful and pleasant person if you need to call. I bought a pump and all the fixin's from him.

This link is to his vacuum chuck page: https://www.joewoodworker.com/veneering/vacuumchucking.htm

JKJ

Greg McClurg
12-14-2020, 7:41 PM
Thanks all for the information. To wire up the pump I assume the ground goes to green, neutral to silver, and hot to copper? Hooking the pump up to the system I would connect the vacuum hose to the "in" and put the muffler on the "out"...correct?

tom lucas
12-14-2020, 7:50 PM
https://www.joewoodworker.com/

Joe Woodworker's web site has kits you can purchased to make a really nice vac system. I purchased one of his kits for a small gast pump that I use in my shop. The Gast pump web site is where I got the information to convert my pressure pump to use as a vac pump, not every pump can be used for vac service.

Bought my kit from Joe too. I priced out the parts separately. Cost was about a wash. So I just bought from Joe. I liked Joe's filter the best anyway. I think there are plumping diagrams on Joe's website too. Or somewhere easy to find on the web. Vac pumps are very simple. Just figure out which port is suction. Add your filter, bleeder valve, and vacuum gauge to it and you are good to go. Easiest switch is an inline switch rated for the in-rush current of that pump. Label say 6.2 Amps max. So I would use a switch rated for 10 amps or more. You can buy power cords with in-line switches. Label says terminal 1 is ungrounded (high side). So that would be your black wire. white on terminal 4. and green attached directly to the chassis (that big green screw).

Kevin Jenness
12-14-2020, 8:17 PM
" I would connect the vacuum hose to the "in" and put the muffler on the "out"...correct?"

Yes. It is a good idea to have a filter on the suction side to keep random stuff out of the turbine chamber. As you can see I have some gauze or similar in the mouth of my bleeder valve too.

Brice Rogers
12-15-2020, 1:02 AM
I have a Thomas vacuum pump and I relied on the "schematic" from the frugalvacuumchuck guy (google it). I went to the local auto store (Autozone) and finally found a clear universal gasoline filter. The schematic shows the placement of a 1/4 turn shutoff bleeder valve which make set up much easier (partial vacuum while you are centering everything, and nice to release a piece after you shut off the pump). It is also nice/essential to have a vacuum gauge. I also made a plug so that when the system is not in operation, I can plug the suction line to keep shavings out of it.

I bought some "sealed" bearings from VXB IIRC and while they are fine bearings, they are "non-contact" (semi) sealed bearings. They leaked so bad that I could only draw 5 inches of Hg. I bought some great bearings at a reasonable cost from Bob, the frugalvacuumchuck guy and can draw a great vacuum.

For tubing, I first tried the clear flexible vinyl tubing and it collapsed under vacuum. Then I switched to the somewhat stiffer poly tubing that is a bit milky colored. It works great and worked with all my fittings.

Greg McClurg
12-15-2020, 10:44 PM
Thanks everyone for your assistance. I got the pump wired up and running, and have ordered the items to complete the setup.

Peter Blair
12-16-2020, 9:44 AM
I have and use this pump. I likely have the paperwork I got with it if you want I can dig it our and send copies to you. Great pump for my vacuum systems both on the lathe and for producing a vacuum when I'm using cactus juice.
Oops I forgot to mention that I put an inline filter with a valve infront of mine so I can 'sneak' up on the vacuum I want. Sometimes the item I want to hold is thin and all I need is a little suction until i get my tailstock it place.
As well when pulling vacuum for cactus juice the container could bubble over if I pull the max right of the bat.

John K Jordan
12-16-2020, 5:28 PM
A bleeder valve at the lathe is a necessity, not only to bring the vacuum pressure up slowly but to limit the maximum vacuum. Too much vacuum on a larger piece that with thin walls can cause it to crack and implode. The pump provides a constant vacuum and the bleeder valve wastes some to reduce the vacuum at the piece.

JKJ

Kevin Jenness
12-16-2020, 6:28 PM
That's a good point, John. When a form is under the level of vacuum a rotary vane pump with a good seal can generate it is subjected to over 10 psi. The area of a hemisphere is 3 x pi x R squared, so a bowl on a 6" vacuum chuck could have nearly a half ton of pressure on it. Anyone who has had an inadequately braced form implode inside a vacuum bag knows what you are talking about.