Need for vacuum guage?

Re: Need for vacuum guage?

Mike Schwing from Md.

>You need a vac gauge. You'll get to know what kinds of pressures things can and cannot take. Snugging/centering a piece of work requires light pressure, then when you finally get it, crank it up. Thin walled work needs lighter pressure, etc..

You at least need some way to "gauge" how much pressure is being applied to the outside of your turnings (thats how the vacs work - air pressure pushes them onto the drum). Whether it be in a hand crank that you get to know well, or an actual gauge is up to you.

Re: Need for vacuum guage?

Bill Howatt

>IMO it is silly to use a vacuum chuck without a guage. How do you know what the vacuum is inside the chamber? You should have a valve that permits you to bleed a little air into the vac chuck so you don't pull maximum vacuum on large thin pieces - it will break it.

You can find guages for $10 or less.

You should also have some kind of a filter on the inlet to keep small garbage from getting sucked into the pump and possible ruining the vanes or other guts.

Bill

Re: Need for vacuum guage?

Lyn J. Mangiameli

>IMO a vacuum guage is essential for safety as well as assisting in matching the vacuum level to the workpiece. I deliberately place my vacuum guage very close to line of sight when I am turning to be able to recognize any unanticipated drop in pressure. Not infrequently hidden flaws, vacuum induced transport of wetness or finishes out of the wood, or excessive thinning of areas will result in a vacuum leak that was not present when the workpiece was mounted. If you can't detect those as they occur, you can end up in a world of trouble from continuing to assume the mounting force you started with is still what you have to work with.

Re: Need for vacuum guage?

Mark Kauder

>My reasoning exactly, Lynn.

Mark

Re: Need for vacuum guage?

Frank

>Thanks to everyone for a quick response. So my next question is what's the best source, and what should I expect to pay?

Re: Vacuum guage

Mark Mandell - Gone Round In Jersey

>McMaster-Carr, No. 3941K53, 2-1/2" guage , $9.00.

M

Re: Vacuum guage

George Balock

>I got the exact gauge and it has been working well for a year and a half now.

Re: Need for vacuum guage?

Fog Tanner

>You really need a quage to tell if you are getting leaks and to let you know what kind of pressure you are putting on the wood. I ordered my guage from Surplus Sales along with some 1/4" brass fittings. I picked up a brass valve, braided hose and more brass fittings from a local hardware store. You can use 1/4" iron and save quiet a bit of money - just doesn't look as good. You need some way to bleed air into the system to regulate the vaucm. Of course if you don't feel the need for a guage, you can always close the valve until the bowl starts getting sucked into your chuck and then back off a click or two :-)

Be sure and use a braided hose that will not collapse. I tried some hose that colapsed, which I thought was OK. I picked 3" hg by switching hose. Went from 23"hg to 26"hg, allowing me to really pull the bowl into the chuck..

Re: Need for vacuum guage?

Frank

>Thanks again to everyone who responded. this helped a lot, and I've ordered a gauge and bleeder valve. looking forward to putting it all together.

frank

Re: Need for vacuum guage? *LINK*

bill noble

>a vacuum gauge is a good thing to have so you know how much force you have holding the item in place. I sell them for $3 each. (note, I also sell vacuum pumps (used) and faceplates). you can find out information on my web page, www.wbnoble.com. There is also a rather lengthy article there on vacuum pumps and vacuum chucking.


Bill Noble's web page