# Simple vacuum adapter Jet 1642 or PM3520b



## TimR (Jul 18, 2017)

Well, the title implies specific to these two, since I've only made one of these and originally for a Jet 1642, circa 2009.
I'll start with how first made for my Jet.

Since these lathes have a thru bore on the spindle, I looked for a way of not having to mess with the extra tube as used on some setups. If I recall, the Jet has a 5/8" stub when the aluminum cylinder hand wheel is removed. 
I started by drilling out one end of a block of hard maple to accept that stub...pretty sure 5/8". The other end was drilled and counterbored for a R8-2RS bearing I had. The OD is 1-1/8, ID is 1/2". 
Use a 1-1/8" Forster or turn on lathe to a depth 1/16" or 1/32" shy of the bearing width. Next, counterbore with 7/8" Forster. Only need to go maybe 1/16" - 1/8" deep, this is relief for the bearing inner hub to not be rubbed.
This way you can use a couple screws and washers to hold it in place, see pic.

Finish boring thru with 1/2". 
If this drilling doesn't make sense, I can try to put together s sketch.

I think the barbed fitting is 1/4", not sure. Take the bearing to a hardware store and find a fitting that will just fit into the bearing or require minimal grinding. I hold mine in place with JenWeld. 
The rubber washer is the O-ring type of washers used on garden hoses.

Ok, so what's with the copper pipe sticking out the end?? When I replaced my Jet with the PM, I discovered the hole in the hand wheel hub of the PM was just a bit bigger than the stub on the Jet...and a piece of 1/2" copper pipe is 5/8" od ,so I just glued a piece in the adapter and left a couple inches to insert in the PM. 
Is this setup completely leak free...hell no. 
If you think it will come out when in use, think again. You have to really pull on it to remove with pump on, even though it so easily slipped on. The leakage is so minimal as to not be a problem for me. Put your vacuum chuck on, and in 5 secs this is ready to go.
I've used this for 7-8 years...works a charm.

Reactions: Like 1 | Way Cool 6 | Creative 2


----------



## Wilson's Woodworking (Jul 19, 2017)

That looks like it should work great. What are you using for a chuck?


----------



## TimR (Jul 19, 2017)

Wilson's Woodworking said:


> That looks like it should work great. What are you using for a chuck?


Get one of these Beall taps, and some mdf and PVC fittings...and some self adhering foam rubber. Closed cell best, but not an absolute reqt

Reactions: Like 1


----------



## Wilson's Woodworking (Jul 19, 2017)

My late has a 1-8 thread and I work in a machine shop so the tap is no problem. The foam comes from a job we cut some seals for so I am covered there.


 

 
Now to get some PVC and fittings for the back end and get to work.

Reactions: Like 2


----------



## Sprung (Jul 19, 2017)

Tim, thanks for sharing! I've been wanting to get a vacuum chuck, but the cost was putting me off and I was having trouble finding info on making my own. Your posts here give me everything I need to make my own setup.

Reactions: Like 1 | Agree 1


----------



## TimR (Jul 19, 2017)

Here's a sketch of the vac adapter...adjust to suit other lathes. (revised at 7:43PM 7/19 to show missing info in text regarding PM3520...and that should be PM 3520b)

Reactions: Like 1 | Informative 1


----------

