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Hi All,

I am starting to get the itching to put together a vacuum press setup. So whats the consensus on the usefulness of such a set up, and what advise would you lend to someone fixin to put one into use.

Thanks
Rob

oh yeah-if you have any pictures of your setup that would be awesome.

I use vacuum clamping very rarely, cause I hate the noise of my continously running compressor, so it sits there . I have a myriad of other clamps. I bought it thinking boy oh boy I get lots of uses. It works, but I prefer to clamp by hand.

I don't own one. If I did more veneer work, I might consider making the leap. Any of the other vacuum clamping tasks I can think of are easily done other ways, so I just haven't bothered.

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Jim Hansen

I find that I use vacuum more and more in the shop. Like Ernie, I don't like the sound of a compressor running all the time, so I built one of the "Joe Woodworker" cycling venturi pumps. It has a tank for holding a reserve of vacuum and only lets air go through the venturi when the tank vacuum drops below a threshold. The compressor rarely kicks on. I use this unit for vacuum bagging--I vacuum bag veneers onto fingerboards/peghead overlays (Its nice not having to deal with all of the veneers slipping around when I'm gluing to the neck, so I do that part in advance). I also use it for applying backstrapping to banjo necks. Works much better than any mechanical clamp I ever tried.

I also have a little piston type pump that I use for clamping. It runs full time, but it's quiet. I make custom clamps for various jigs in the shop (mostly for CNC work, but I use them for hand work too) by routing a 1/4" slot in the shape I need and then pressing foam cord into the channel to make the clamp. These are great for holding fingerboards when I'm inlaying and engraving in particular. I can chuck one of these jigs up into my engraving ball and it really holds things solid.

I've posted some pictures here on the forum of my backstrap vacuum bagging as well as some of my clamps. I'd really have a hard time living without a vacuum system in the shop any more...

Dave

I have a vacuum setup and I like to use it to glue bacing on the top and back. The noise doesn't really bother me. I use this setup instead of a go bar deck. Seems to work well for me...

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Interesting-
Thanks for the responses.

@sdsollod- What size bags are you using for gluing the bracing? Do you have to make any modifications to make sure that the back glues to the radius of the braces?

Thanks again-

any other input would be great.

Rob

Just over a year ago I made a Joe Woodworker set up with vacuum tanks and a mac valve etc so the pump does not need to run all the time. It also has a foot pedal valve switch so you can hold the work piece in position with both hands while being clamped and the only vacuum lost from the system between clamping operations is that which was in the lines 1/4" between the foot valve and the project.



I have really only used it for clamping as in holding things in position whilst routing etc and I like it a lot. I am certain I will get much more from it if I bothered such as bridge clamping and such and even have the alloy bridge clap with membrane all set to go. But most all of the work I have done since I built the rig has been repairs, and in that application, to re-glue a bridge it takes more time to seal up the pre-existing bridge pin holes securely than the clamp would save.

Its a fantastic thing though for holding your guitar on its side when working on bindings etc so for that function alone it was worth building it...I do have a large bag to do some veneer work later but have not unpacked it to date.

Oh yeah..I've put casters on it since that image was taken...makes a good upgrade.

Cheers

Kim

I have used vacuum clamp system since 2005 and working in a shop that uses it. Since then never looked back and prefer it much more than go bars.

I initially used the vacuum compressor from LMI, but not with good success. Since I bought a larger unit I from Joe Woodworker and at a better price. I guess if using an air compressor one would have some noise in the shop on occasion as it recharges or whatever it does. But in one can build the system Joe does and not have that problem or less of it. I don't use an air compressor system and I don't have any noise problems at all. My compressor is in a cabinet and I have a switch to to turn it on and off and only have it running when doing braces or bridges. I have not built the rig that Joe has on his site. Also I use 3/8 nipple and hose and not 1/4". I have gone back and forth on drilling holes in all the sides of the tubing. I used to use the LMI rubber, but now use the stuff Joe sells. Again, get more and for less money. I now have the thin stuff on and not a problem with tear and easier to put on the frame. I have used several kinds of closed foam seal for the bottom of the frame, but now settled on the stuff like Joe sells, but can't remember if bought it from him or not, but I think I did. It comes in a large roll and unless one makes a bunch of presses, it will last for years. Much better seal than stuff from big box stores and used for weather sealant

My system is based of one by Bob Garrish (a member here) and bought from Bob. After mine was messed up in a move, I asked him if it OK to use his ideas and then built one. Mine is aluminum 1" square tubing. I would note if doing this, make sure your welds at the mitered corners are will sealed. I eventually put in the closed foam stuff used on the bottom of the frame in the mitered corners, but I am not a good welder and had some pin holes. The foam closed it up tight. I guess one could use putty or other stuff, but I used what I had in the shop. It doesn't take much of a hole for a leak that will mess you up. I use 1" aluminum angle to secure the neoprene or whatever the stuff is that makes the clamp. I do not have a base that is attached to the top, but I am working on that. Now I use an old base I had and sealed with shellac and epoxy. I get 22 to 26 Hg ( I think is the measurement) of pressure.

Using this I put the braces in for about 15 minutes and then clean glue. I then turn on the system for another 10 minutes or so. Probably don't have to do that, but just a habit from old shop. I have not had any glue failures due to the system, and when have had a problem, it was due to the adhesive I was using and concerned about prior but like an idiot used it anyway.

My bridge clamp is acrylic I bought from Bob when he first made and sold them years ago. I don't know if Bob still makes and sells these things, but if he does and one is looking to buy, I would highly recommend his rigs.

I am not saying vacuum is the best, but for me it is. The boss made up a rig in his shop and then didn't use it and continues with go bars which he likes better. To me vacuum is faster and easier to use, but to each their own. If I could figure out a way to use this kind of system for gluing on the tops and backs, I would give it a try. But that is a deep press. I use this for both new builds and repair work, particularly on bridge stuff.

Looks to me like I should check out this joe woodworker vacuum clamping. Good to learn new ways of doin things.

For bracing, once you go vac, you never go back!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I use a vac bag for bracing. I think it is a good way to go.... I use the QVP NuMatic. It WILL run with a small pancake portable...but not really well. I now use a 30 gal Craftsman, to better results.

Dave Nichols at Custom Pearl Inlay, uses the same rig, in constant use for years now.

I once called the QVP guy at 9pm one night , he was very gracious, and helpfull. Nice people, product, .....been around for a long time.

How do you use your compressor to generate a vacuum? Do you connect a hose to the air inlet, or do you use a venturi?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Rob, Sorry for the delay. I haven't checked the OLF in a few days...

Some folks may consider my setup kinda crude... I made a simple frame with MDF and glued a sheet of plastic over it. I put weather stripping around the frame. I have a (I think it is medical grade) used vacuum pump from ebay [I can't remember the name right now, but it was pretty cheap ~ $50.] I run tubing to a nipple that goes through the plastic. I place my top or back with the braces I have applied glue to on top of the appropiate radius dish, which I sealed with epoxy - then place the framed plastic on top, place clamps around the frame and radius dish to ensure a good seal, and draw the vacuum. The vacuum pulls the top or back into the radius dish and applies the pressure needed to clamp the braces tight. ...Piece of cake!

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Here's another vote for vacuum clamping of top/back braces. If you do double/laminated sides or double tops it's a must have IMO.

Great Info everyone-
Thanks for the tips and advice...

Second that!! Although to be honest I have never tried any other way.

Here is a pic of my vacuum press in action. The frame is 1x2 birch... don't recommend this, its kinda weak. I will use something stronger next time. Frame to hold the rubber on is some mahogany I had laying around. Rubber is the thick stuff from LMI. Not sure where the foam seal is from as Rick Davis was kind enough to give me some that he had left over.

Currently I am using the venturi from LMI but am going to switch to a dedicated vacuum pump as soon as finances allow as the compressor running all the time is annoying. I just use the top of my workbench (its is smooth flat and non porous) as the bottom. Got the basic design off the Joe Woodworker site. Works great.

One note... I have a double sided radius dish. If you have one of these make sure you brace underneath the dish before applying the vacuum. Otherwise the pressure will flatten the dish out a bit and you will not get the correct radius.

Can some one post the specs they use on the dedicated vacuum pumps ?

is this good / even though I don't know what it means -

Capacity up to 4.40 cfm / 124.65 l/min
Vacuum to 29.0 in.Hg / -982 mbar

are there any suggestions as to what specs we should look for ?


Found my answers on joe Woodworker -

from his page -

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It's this new idea from recent decades that everyone gets a participation award. - MUX