About Vacuum Forming

[Denster]

Particle. I see your problem. The screw in the end of the tube opposite the vacuum gauge needs to be backed out to about 3/4" and locked with the nut. Without going into a long detailed explanation of why it is there it is not needed for our purposes so back it out an lock it down.

I also presume that you have the red handle at 90deg to the air filter when you start the pump and only turn it in line with the filter to release the vacuum.

Small holes in the bag can be fixed nicely with a piece of duct tape.

[particle]

Thanks Denster - I'll give that a try. I was never sure what that little brass thing was for, so good to know it's not needed! I actually never actuate the red lever. I never noticed it doing any good, so I just leave it alone. I always just figured I got a faulty pump, but once I figured out it wasn't holding suction, I'd already thrown all the packaging away and couldn't send it back.

[electrathon]

I have pretty much the same system and it works well. I find I'm running low on the pump oil. Does anybody have a good source for the "High Vacuum Oil" for the pump? I don't find it at Harbor Freight (where I got the pump). Is there an automotive equivalent?

Any shop that sells air conditioning parts will have oil. It is a mineral oil like was used in the old days with R12.

[supercub]

Any shop that sells air conditioning parts will have oil. It is a mineral oil like was used in the old days with R12.

Thanks, found some at NAPA.

[Dwight]

I got mine from McMaster Carr, . . .

Remember that name, . . . write it on a stickey note, . . . don't lose it.

Other than groceries, . . . I don't think there is much they don't carry for the mechanical / working world.

Sometimes they can be a bit on the pricey side, . . . but they have supplied stuff for me since somewhere back in the early 90's.

AND, . . . if you order it before 4 in the evening, . . . you can look for it the next day. I used to marvel at that when their nearest location was Chicago, . . . I'm just north of Columbus, Ohio, . . . I had it at 10 the next morning when the big brown UPS van backed up to our door.

May God bless,

Dwight

[Denster]

I second what Dwight said about McMaster Carr. If they don't have it no one does.

[Jaymack]

What do youy use for the valve on the vacuum bag?

[triage1998]

I have the exact setup as Particle. Thanks to Eric for the wonderful thread about a year ago. Its a pricy setup but my holster look better than they ever have with his setup

[Dwight]

What do youy use for the valve on the vacuum bag?

I don't. My pump goes directly to the bag, . . . no valve, . . . no filter, . . . just a 3 foot long section of black rubber gasoline hose.

I keep my bag clean on the inside (as much as I can ), . . . always put the holster a ways away from the intake, . . . and I use a rod or something that channels the air from the holster area back to the pump intake.

Turn on the pump, . . . form, . . . turn off. Maybe slightly re-position the bag or the gun or the holster. Turn on the pump, . . . form some more (detail type stuff), . . . turn off. (Repeat as many times as necessary for that particular piece of work)

All has worked well so far.

About 5 seconds after I turn the pump off, . . . the vacuum will break, . . . and air will start migrating back into the bag.

May God bless,

Dwight

Edited July 27, 2013 by Dwight

[hestes]

Here is the platen I made. Ignore the string - I don't use it anymore. I just butt my dummy gun up to the platen - that allows enough air gaps to keep sucking air out of the bag.

So you put it in the bag with your holster to create some space to allow for more air to be pulled out? Is that all that is for?