Powermatic Vacuum Chuck Question

[seebs0945]

Hi All,
Need some advice as to how I should adapt my Powermatic 3520B to accept a vacuum system. I already have the pump from my previous lathe but the adapter I have was mounted into the handwheel and held there by a set screw. The 3520B does not have this recess in it's handwheel. I am sure that some of you have done this. Any advice would be appreciated.
Thanks

 

[Jim Keenan]

See the last post on this link
http://www.aawforum.org/vbforum/showthread.php?t=731&page=2

 

[57_T-Bird]

Hotglue fix ?

> 3520B does not have this recess in it's handwheel.

I once used hot melt glue to attach a circular block to the handwheel.
Then it was turned round and and also turned to accept the vacuum adapter.

T-Bird

 

[john lucas]

I had a machinist friend drill my handwheel to fit the bearing system I use for my vacuum pump. I simply put a piece of closed cell foam in the opening and then insert the bearing assembly. It stays in place quite nicely. I do cut a center hole in the foam.
Before this I used a lamp rod assembly to connect everything but this required removeal for other projects and you to unscrew the thing. The large rebate in the handwheel is much better and faster.
I'll try posting the jpg on here so you see how I build the bearing assembly and the lamp rod assembly.

 

[john lucas]

I had my handwheel bored to fit a simple bearing assembly. I used to use a lamp rod assembly that works well if your lathe spindle has holes or leaks the vacuum. I put a gasket made of a think piece of closed cell foam in the handwheel rebeate to seal the bearing. This works extremely well and is quick to remove. I don't see why you couldn't just glue a piece of MDF that has been well cealed with lacquer of some other finish, onto the hand wheel and then bore this for the bearing. If I remember correctly I had to put some clear silicone cauling on the inside of the handwheel when I re assembled it to stop some leaks.
The bearing assembly is simply a Nylon barb to screw thead adaptor. I buy a bearing with 1/2" hole and then force the theaded adaptor into the bearing with some epoxy. I have also used brass barb to thread adaptors but you have to turn the brass thread down just a hare to make it fit the bearing.

 

[Turnedoutright]

Shop made vacumn adapter

See my post at www.Turnedoutright.com Vacuum Adapter.
I am using this with three lathes:

• Mini jet
• Large jet
• Stubby

Perhaps it can be adapted to a Powermatic as well. Except the bearing (McMasterCarr) everything came from hardware store.

Donnie