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View Full Version : One step closer to finishing my vacuum chuck. I made a rotary adapter!



Joshua Dinerstein
02-19-2010, 1:39 AM
Following the in the footsteps of many here I have been working for oh... the last year on a vacuum chuck system. It has only taken that long because within weeks of buying my pump and parts my wife and I had a baby. Katie being my first I had NO CLUE!!! how much time and effort she would take. Worth it to say the least but other things had to take a back burner. In the last week I finally got around to trying again.

Following a picture and an explanation from Don Orr I made my own rotary adapter.

I got some Corian samples from a local store. These about 2"x2" and 1/2" thick. They were highly polished and had been written on. I didn't think glue would hold something that highly polished so I put my sanding wheel onto the lathe with 2 quick swipes, one on each side, with an 80 grit disk it was now nicely roughed up. I put some CA glue on the top surface of one piece and while quickly trying to decide how to smooth it around/out without glueing a brush to the surface I just took a second and tried to do a thorough smearing. It worked very well.

Once all 5 pieces of Corian were sandwiched with Glue I wrapped it in a paper towel. No purpose there except CA glue was getting EVERYWHERE. :) I then got out a double screw wood clamp, great for getting large even pressure across across 2 parallel surfaces and a HF special to boot. I let it cure over night just to be sure. CA glue should cure much faster than that but I wanted to be sure.

This last Sunday morning I started working on the turned and made it into a round cylinder and the cut the recess for the double sealed bearing and brought in the sides just enough barely slipping into the hand wheel of my Mustard Monster. All in all it took me about an hour to turn. Mostly because I have never worked with Corian before and it took me a while to figure out how to get clean cuts on it.

I then, again follow Don's comments, turned down a HF hose barb on the lathe so that it would fit inside of the bearing. This was remarkably easy especially after the corian. I cut 2 shallow grooves on other end for some O-rings. The one mid-way down is smaller than the one at the base. That was so that it would just barely slip in. The larger one gets drawn in and seals tight once the vacuum is applied.

I test it and it works perfectly. Almost no pressure stops the barb from rotating even at high speed. I then followed this up by making a tapped wooden faceplate as the core of the mounting system. As soon as that is done I will be ready to use it. It is glued up and trued up. I just have to mount the foam I bought.

I am at the moment not sure of the best way to attach the closed cell foam to the surface of the faceplate. Anyone have any suggestions? Elmer's white glue? Wood glue? CA glue? I was just planning to use some wood glue but will change up if someone has another suggestion.

Fun stuff working on this one! And not to shabby for about $2.64 in materials. The most expensive part was the bearing. OK so I had to buy 10 of them and have 9 left but who's counting and overall costs are just a tad more... but I will find a use for them at some point.

Joshua

Richard Madison
02-19-2010, 1:58 AM
Looks good from here Joshua. Might want to make a few more (9 bearings left) for some friends, for a nominal fee of course. Just a thought.

Dale Miner
02-19-2010, 9:26 AM
I used a thin spread of white silicone RTV (bathtub caulk) to attach the foam. It retains moderate flexability when cured.

Later,
Dale M

Steve Schlumpf
02-19-2010, 10:16 AM
Nice work Joshua!

I did not attach the closed cell foam to the chuck. Instead, I cut a small X in the middle of the foam and hold in place between the chuck and turning when lining it up. Once vacuum is applied - it is not going anywhere! This way - should the foam get ripped, dirty or need to be replaced - I am not messing with any glues and simply grab another piece of foam.

steven carter
02-19-2010, 10:35 AM
Joshua,

good job on the rotary adapter, looks like it should work just fine. I use the foam with adhesive on the back, it doesn't want to hold all that well on the inside of the drum, but says in place enough that I don't have any trouble using it.

Steve

Chris Stolicky
02-19-2010, 11:32 AM
Nice adapter. I was working on one with my FIL a few week back and it is definitely a more thrifty way of handling the task (I purchased an adapter). I now kind of wish I had made my own.

As for the foam, I simply do what Steve does and haven't attempted gluing anything.

Bernie Weishapl
02-19-2010, 11:41 AM
Great looking adapter Joshua.

Jon Finch
02-19-2010, 12:06 PM
looks great. 3M Super77 spray adhesive works great for gluing down foam.

Joshua Dinerstein
02-19-2010, 4:46 PM
Interesting. That is why I love posting here. I often get new and different perspectives on things. I had planned to glue it down so it was fixed in place. I had planned that... just sort of because. I read these posts and stopped and really thought about this latest assumption.

I had been planning everything up to and including using J roller to really get it down onto a solid glue bed. I am dropping all of that entirely.

I think that I would still like to tack it down in just a few spots so that I won't lose the foam in my shop when not in use. But now just a few drops in the right place, probably in the middle near the drilled hole, should be sufficient. then if I ever have to change the foam it should be easy.

I have to go and try to find something larger somewhere. What I bought was 2 12"x16" sheets. My wooden faceplate is 16" in diameter. so I need some larger sheets to get a solid circle out of. Either that or to make some smaller faceplates of different shapes.

Anyone have a source for getting larger sheets from?

Thanks!!
Joshua

Thom Sturgill
02-19-2010, 7:46 PM
A flat plate is good for bowls with even rims, but a vacuum chuck really shines when used for irregular items. I have a set (2.5",3",4",6") pvc pipe joints mounted to threaded MDF plates with the thin closed cell craft foam attached to the rim. I have mounted HFs and NE bowls on them. Larger is better as you get more force, the small one is nearly too small and requires very light cuts, but then I'm using one of those venturi effect vacuum units.

Joshua Dinerstein
02-22-2010, 1:32 PM
A flat plate is good for bowls with even rims, but a vacuum chuck really shines when used for irregular items. I have a set (2.5",3",4",6") pvc pipe joints mounted to threaded MDF plates with the thin closed cell craft foam attached to the rim.
These are on my list. I have the PVC couplers purchased and sitting at home. I don't have the wooden faceplate blocks threaded or turned yet but I will do so soon. One piece at a time. :)

Thanks for point these other varitions out.

Joshua