PDA

View Full Version : DIY vacuum chucks.



Roger Davis TN
08-24-2018, 10:34 PM
Hello all, I have put together the Frugal vacuuming system except for the chucks. Could someone give me advice as to what kind of chuck works best. The 3 PVC pipes of different sizes, a face plate type or something better. I have three bearings and tubes, so I plan on using all parts. Just want to make air tight chucks that will hold bowls. Thanks, you guys are a big help. Roger Davis.

Dwight Rutherford
08-24-2018, 10:58 PM
I use PVC in various sizes. They work well for me.
Don’t know why they are upside down.

JKJ edit: rotated

392219

Brice Rogers
08-24-2018, 11:32 PM
I made the type of vacuum chuck that has a tenon on it and can be held by my regular chuck. So, it is a piece of wood with a tenon or one side and a groove for a PVC fitting on the other side. In the center is a bearing and tubing fitting held in place with 3 screws. I sealed the wood to minimize leakage. I had two sets of jaws for the regular chuck, so I made two different sized dovetail vacuum chucks - - a small one (2-1/2" pvc iirc) and a larger one (3-1/2" pvc iirc). The small one has 5 square inches of area, so if I'm pulling 24" Hg, that is 60 pounds of holding power. The bigger one gives me 2X area and holding power. So far, I haven't had any pieces that let go. But I take light cuts and am just shaping the "foot".

On the larger one I tried to get fancy and folded the foam on both sides. On the smaller one I just used silicon rubber to glue a foam "washer" to the lip. It doesn't look as neat but it works just as well.

The other day, I had a turning that was between the sizes of the two chucks. Neither fit right. So all I needed to do was to put a 6" disk of masonite (hole in the center) on the chuck and then put another foam pad on the other side where the bowl clamped on. Worked perfectly.

John K Jordan
08-25-2018, 12:06 AM
Hello all, I have put together the Frugal vacuuming system except for the chucks. Could someone give me advice as to what kind of chuck works best. The 3 PVC pipes of different sizes, a face plate type or something better. I have three bearings and tubes, so I plan on using all parts. Just want to make air tight chucks that will hold bowls. Thanks, you guys are a big help. Roger Davis.

I have some made from PVC couplers fastened to flanges with a threaded adapter to fit the lathe. If your lathe spindle thread is 1-1/4x8 tpi you could borrow a couple to try.

I think Doc Green's book "Fixtures and Chucks for Woodturning" has some ideas about making some. I don't remember, but he might have something on his web site too.

JKJ

Jeffrey J Smith
08-25-2018, 1:15 AM
You might consider the precision vacuum hub from JT Turning Tools. Been using one for about 7 years now. One hub, interchange 2” PVC adapters (2”, 4” and 6” are the three I use most often. Simple changeout with an o-ring seal. True up the adapter face, use a little 2mm closed cel foam for a seal and you’re good to go.
You can do the same thing with wood or mdf and a tap for your spindle and make your own, but this one was leak proof right out of the box and has seen steady use for several years without a problem. Its stayed trued up, too (as long as I remember to draw a vacuum before tightening the set screws). With the o-ring seal the set screws are a little like “belt-and-suspenders’ engineering
Not terribly expensive for what you get...

Paul Williams
08-25-2018, 2:17 PM
I use PVC adapters. 1 1/2 or 2 inches on one end and 1 1/2 to 4" on the other. I got some machinable plastic or nylon from surplus dealer. I turn a cylinder to fit one end of the adapter. Hold the other end in the lathe and true up the end and shorten it to be just a little longer than the thread on my headstock. Then drill and tap the nylon plug. Turn it around. Thread it on the headstock and shorten and true up the other end. I add thin sticky hobby shop foam for the seal. Relatively new to vacuum chucks so not a lot of experience with this method but so far they seam to work very well.

Thomas Canfield
08-25-2018, 10:20 PM
I would advise making an adapter to fit the bore of your headstock with one bearing, and then making many different size chucks with wood block tapped with Beale tap to fit your drive. That allows much more flexibility and very little cost.392233392234
This shows homemade adapter for Powermatic 3520B and Nova Comet II and some of the homemade chucks. I have chucks made in both 1" and 1-1/4" in about 5 sizes each including flat plates.

Dane Riley
08-25-2018, 11:30 PM
I would advise making an adapter to fit the bore of your headstock with one bearing, and then making many different size chucks with wood block tapped with Beale tap to fit your drive. That allows much more flexibility and very little cost.
This shows homemade adapter for Powermatic 3520B and Nova Comet II and some of the homemade chucks. I have chucks made in both 1" and 1-1/4" in about 5 sizes each including flat plates.

Second this. I made mine with a brass fitting and cut some groves for O rings392235

Roger Davis TN
08-26-2018, 12:23 AM
Thanks guys. This gives me some things to think about. Brice Rogers has a good idea of just placing a disk on the vacuum chuck to accomadate larger bowls. I do have a one and a fourth by eight lathe, John (Nova 1624-44).Maybe you could show me how the die works? I was thinking about getting one. The other ideas are not in my scope of knowledge. I am a novice turner. All of your ideas are appreciated even if I do not understand. Dwight, Jeffrey,Paul,Thomas and Dane, all are very helpful and hope I can return a favor someday. God bless all of you and I do enjoy Sawmillcreek. Roger Davis

Pete Staehling
08-26-2018, 6:51 AM
Roger and Dane, can you say a little more about how you fitted the adaptor to the bore of the headstock. It is a straight cylindrical bore at that point right? I am guessing it is just a snug friction fit? Seems like that would be fine especially with a couple o-rings fitted.

I like this idea. I have a dozen 1" x 8 tpi nuts that fit my headstock so I can get by without even needing to buy a Beale tap.

Thomas Canfield
08-26-2018, 8:10 AM
Thanks guys. This gives me some things to think about. Brice Rogers has a good idea of just placing a disk on the vacuum chuck to accomadate larger bowls. I do have a one and a fourth by eight lathe, John (Nova 1624-44).Maybe you could show me how the die works? I was thinking about getting one. The other ideas are not in my scope of knowledge. I am a novice turner. All of your ideas are appreciated even if I do not understand. Dwight, Jeffrey,Paul,Thomas and Dane, all are very helpful and hope I can return a favor someday. God bless all of you and I do enjoy Sawmillcreek. Roger Davis

Go to the Beale website and they show how to tap using the lathe. I have developed a method of using my drill press at slowest speed to tap my faceplates holding the faceplate with a strap wrench. Tap will engage the plate and lift it up off table and thickness of plates allow the tap to go through and spin. Much faster.

Roger Davis TN
08-26-2018, 10:55 AM
Thanks, I did. Looks easy. Roger

Dane Riley
08-27-2018, 6:47 PM
Roger and Dane, can you say a little more about how you fitted the adaptor to the bore of the headstock. It is a straight cylindrical bore at that point right? I am guessing it is just a snug friction fit? Seems like that would be fine especially with a couple o-rings fitted.



The O rings are snug. I do have a holder to hold the hose and provide a bit of pressure to keep it from falling out.