Vacuum Chuck Gasket

[Wyatt Holm]

Hello,
I have been working on my vacuum chuck and everything works fine except the rubber sealer. I first tried foam weatherstrip, It worked quite well, but it was to soft and the pvc pipe I am using for the drum shuck would mar the surface. Then I tried Neoprene from csusa It also worked but It was about 1/4" thick and too soft some my bowl would move. Mike Mahoney said plumbers gasket, I tried it also but it is too hard and does not create a good seal. So I sent a email to a rubber company because they have many neoprene and rubber sheet. What density would be about the right stuff? I think I would rather some soft rubber than the neoprene. I am open for advice.

 

[Rob Wallace]

Wyatt:

I have used the closed-cell foam (usually about 1/8" thick) that is sold at art/craft stores (Michael's, Hobby Lobby, etc.) that is used for various art projects. I almost always buy black, but it comes in a range of wild and exciting colors!!! It works pretty well and is fairly inexpensive. If you're looking for more "permanence", Craft Supplies sells gasket material for vacuum chucking by the sheet, but is it is somewhat thicker and a bit more costly than the craft foam sheets mentioned above.

Good Luck!

Rob Wallace

 

[john lucas]

I also use the craft store closed cell foam. I have used "0" rings but you have to make your chucks a very specific size. I now use some round neoprene foam gasket material but it does have some give to it. Most of the time it's not a big problem because it compresses pretty far.
I've also used truck camper gasket material. It's kind of messy to use and wears out with frequent use but you get a huge roll pretty cheap. The downside is it is only 2" wide. I sealed the joints with clear silicone rubber. I used this for years before finally looking for better gasket material.

 

[Vernon Oberle]

Packing material

I use the 1/8 inch packing foam from Uhaul or probable many other places. It's relativily cheap and easy to use with a little 3m 77 spray on glue. I learned this from David Lancaster if I remember right. I am still using the first package and have given some to friends. It dosen't last as long as the neoprene but I am more willing to change it when it gets worn.

Vernon

 

[Mike Peace]

I have also used the "Fun Foam" from Michaels. I use white. $1 a sheet for about 12" by 18". I believe it is more like 1/16". It is closed cell. I did not have good luck with the packing foam.

 

[hockenbery]

yet another Fun foam user Like John and Rob described.
We use the deluxe version with the self adhesive back.

I have a few chuck made from pvc I use the schedule 80 which is thicker
round over the sharp edges. Even with the round over the pvc will cut through the foam maybe 4-5 turnings. It is only a 2 minute job to replace the foam.

You have mastered the basics of vacuum chuck foam.
thick spongy foam gives the best seal but also a bit a spongy feel when you turn what is mounted on it.
Our Michaels has a thick and a thin. If you have to remount an old not with round piece the thick may do the trick.

wooden chucks we use for bowls and platter have a wider surface and the foam on them lasts through dozens of pieces.

Happy Turning
Al

 

[Wyatt Holm]

Thank You everyone. I am thinking about ordering a sample box from the rubber company if I can. What densities and thickness do you recommend?

 

[Steve Worcester]

I don't remember if they have minimums, but they have closed cell sponge with adhesive back. I have bought some before, but not this exact thing.

http://www.allstategasket.com/info_gasket_material_buy2.asp

 

[woodturner1951]

Tire Tube as gasket?

I have seen some threads and chuck construction pdf's that recommend the use of tire inner tubes as gaskets. Since these are readily available at tire repair shops, has anyone using or tried this rubber material? I have used neoprene, various closed cell foam materials and other materials with mixed results.

Still looking for the optimum material.

 

[john lucas]

As a bicyclist that is the first thing I tried. It is too thin. If your bowl happens to be perfectly round and your chuck is also then it will work. If anything goes awry it won't. That is the advantage of the thicker gaskets. You can get away with much more but you give up the rigidity.

 

[plamb]

Fun foam

I find fun foam from Michaels works very well. No movement when reverse turning. It was recommended by Al Stirt at Richmond Symp. I support his recommendation.
Peter

 

[Jim Keenan]

Go to the home center into isle with the ABS plumbing fittings. Look for the rubber end cap witht the hose clamp. Find the size that fits your piece of pipe, punch a hole in the middle,smear some silicone all the way around in the cap, put it on the pipe and tighten it down to cure. After curing, remove the clamp, put it on the lathe and true it up with abrasive. Works great!

 

[woodturner1951]

Tire Gasket

I agree with you about bike inner tubes. I was wondering about using the heavier truck tire tubes. I think I will hit the repair shop today, make a couple and report back next week on the success of this.

 

[Wyatt Holm]

I ordered a sample box of rubber from Rubber Cal. Most of their stuff is to hard and dense. But there were two pieces that looked like good candidates. I will try them out and see how well they work.

 

[williamwestbrook51]

leather

Yes I use leather as a gasket. I get the leather from your local automotive seat and headliner repair shop. They all have a scrap bin where they collect end pieces. It does not take very much leather to make a real good gasket seal for your gasket seal. I have used just about everything out there and find that this is the best.
I have sent along some pictures that show how I get the leather ready to shape and glue to the vacuum chuck. Hope this is helpful in showing another way to take care of the problem.

 

[pnwradar]

I went to the IT guys at work and asked for some mouse pads. They had a boxful of freebies from trade shows and computer vendors. Like the bear family porridge, some were too thick, some were too thin. Some are now in the shop, helping things spin.

-jon-

 

[ThePenSmith]

I also use fun foam, it is a great and inexpensive way to accomplish a task like this. I glued mine to glued up sets of MDF from lowes. I turned various sized bowls and lined the rim with fun foam and it works great...

 

[Joe Greiner]

I've used the craft shop foam for a jam chuck. Probably more compression than a vacuum chuck. It transferred some color to the wood, easy enough to sand away. Next time, I'll use white or a color with less contrast, or food film interface.

Joe

 

[john lucas]

Sometimes computer parts come packed in the perfect material. It is a white closed cell foam a little less than 1/4" thick. I made some chucks for a friend using that stuff. It works great. Glue it on with clear silicone caulking.

 

[n7bsn]

I had a can of spray-on undercoating that I tried, didn't work. Too hard, too thin and took too long to cure.

 

[Max Taylor]

I have just bought a scrap piece of thin, soft leather for gasket material. Slightly rough on one side turned out. Tried it out on a couple pvc chucks, works great. Plan to experiment more in a few days. Will post if it works satisfactorily. Cost was 4 frogskins, enough for 5 or six gaskets. Max

 

[woodturner1951]

Vacuum gaskets

I tried the heavier truck tube gasket and it works just fine for me. I also experimented with a closed cell neoprene, I got at harbor freight that is used to line the tool chest drawer bottoms, it worked equally as well. My favorite is still the thicker neoprene material.

I modified my chucks, homemade out of PVC or ABS, with a threaded hard maple bottom. I turned and inserted an MDF donut (about 1" wide) in the top of the chuck to give the gasket material a larger glueing surface. Instead of just the diameter of the pipe, the surface is now about an 1" wide and the the chucks work far superior now and I am drawing more than enough vacuum for my needs. I am getting a better grip here than from any of the commercial vacuum chucks that I have.

If anyone is interested, I will start a new thread on chuck design.

 

[Ed Koenig]

I stumbled upon this web site yesterday while searching for a supplier of neoprene foam. http://www.foamandupholstery.com/neoprene.htm

The prices seem very good to me for the size sheet. I think one sheet might last me forever! What do you think?
Be well.
Ed