nova lathe vacuum adaptor SUCCESS! WIP

[Woodmonkey]

Anyone know where I can source a vacuum adaptor to fit a Nova lathe? The part is listed in the manual but a trawl of the net only brings up US sites, wondering if it's available anywhere in UK?
Cheers

 

[bobham]

The rotary adaptor for vacuum chucking that Teknatool used to sell for the Nova lathes was intended for use with a shop vac as the vacuum source rather than a vacuum pump. To the best of my knowledge they no longer sell that piece. They don't list it on their website, anyway. It was a very simple piece that was basically just a short length of 1" O.D. thick walled pipe with one end turned down to a press fit in the inner race of the bearing. The outer race of the bearing was sized to fit the recess in the outboard hand wheel of the lathe. There were two holes bored and tapped in the side of the stub of pipe that stuck out from the bearing. One of the holes was used to anchor the vac hose on the pipe stub and the other provided a bypass air flow to avoid dead heading the shop vac. The original bearing from Teknatool was an NTN 6004LB. When my bearing finally seized after 5 or 6 years of use I was able to replace it with an SKF 6004 2RSJ that I purchased locally. I still use mine on almost every bowl I turn.

I would think that any machine shop could make up the pipe stub very easily for a reasonable cost, but I have never looked into it.

You can see a bit more of mine in this video: https://www.youtube.com/watch?v=YBgGm7xIfQ0
and I show the bearing replacement in the latter half of this video: https://www.youtube.com/watch?v=3mFl3dxV6xM

I don't know how the adaptor could be made to work with a vacuum pump based system but I am sure it could be cobbled together somehow. It works surprisingly well with just a shop vac as the source.

Take care
Bob

 

[gregmcateer]

Thanks for that info, Bob - I'll mark it for future reference!
Greg

 

[duncanh]

I never had any success with the official Nova adapter and made my own using bearings, wood and copper pipe. It was permanently attached to the hand wheel.

I may still have the official adapter if I can find it (and that's a big if) you can have it

 

[gregmcateer]

Duncan,
Would you be kind enough to put up a picture and dimensions of the one you made?
That would be really helpful.
Many thanks in advance,
Greg

 

[Woodmonkey]

Bob - thanks for that, yes it was just my shop vac I was hoping to use. I had a feeling it might have been discontinued due to the lack of search results. What do those long numbers refer to, is there some sort of international standard for bearings?

Duncan - that's a kind offer, if you can find it that would be great, otherwise some more detail of how you constructed your own would be really helpful.

Thanks men.

 

[gregmcateer]

What do those long numbers refer to, is there some sort of international standard for bearings?

Seems to be, WM;

http://www.qualitybearingsonline.co...x-42-x-12mm/?gclid=CIvIwrSPg74CFWXnwgodzlAAGg

Looks quite do-able, even for a klutz like me...

 

[bobham]

Hi, Duncan:
Were you using the Teknatool adaptor with a shop vac or a pump? I can see that it might be easier to start from scratch if you are going to use a pump but the Nova adaptor seems to work well for me using a shop vac and 1 1/4" hose. I do recommend boring the bypass air flow hole in the vac hose to keep the vac from dead heading. I originally did not and it only took about a year before my shop vac wore out. It was, admittedly, and older and cheaper shop vac already before I started using it for chucking, so it may have been ready to die anyway, but I did not notice any difference in the grip of the vacuum chucks after I bored the ~1/4" bypass hole.

The shop vac will certainly not develop anywhere near the degree of absolute vacuum that a pump will develop, so you do need to keep your expectations reasonable and maximize the surface area of the piece that is actually under vacuum.

Take care
Bob

 

[Woodmonkey]

So just to clarify, the bearing mentioned in the link above should fit exactly into the recess in the handwheel of the lathe? It's just tight enough that it stays in by itself? Then I need a short length of pipe closed at one end, which will fit tightly inside the bearing, with one hole for the hose and one hole as a bypass? Doors it matter what the pipe is made of?
Cheers

 

[gregmcateer]

So just to clarify, the bearing mentioned in the link above should fit exactly into the recess in the handwheel of the lathe? It's just tight enough that it stays in by itself? Then I need a short length of pipe closed at one end, which will fit tightly inside the bearing, with one hole for the hose and one hole as a bypass? Doors it matter what the pipe is made of?
Cheers

I would love to know as well. Though WM, I think you may have mis-read or mis-watched Bob' video - The pipe isn't closed at one end - it has to be hollow to allow the air through. What I THINK it means is maybe swaged(?) over at the end so it stops the pipe slipping out form the bearing.

But what do I know!?!

Bob / Duncan - Please enlighten us.

TIA

Greg

 

[finneyb]

Some guy called Paul Hannaby has an article that looks useful http://www.woodworkersinstitute.com/page.asp?p=2156

Brian

 

[gregmcateer]

Some guy? Some guy!?!

The famous Paul Hannaby is a member here and on the WWI forum. Top man and a good teacher, (despite the poor student!).

Seriously, though. Thanks Brian for posting the link - I have read it and it is useful and detailed. I just hadn't realised it's possible to use a normal shop vac, so was keen to find out about this cheapo way.

Greg

 

[Woodmonkey]

Aaah thanks Greg, just watched bobs video, makes sense now

 

[bobham]

The Nova hand wheel that was on my DVR had a threaded hole for a set screw to snug on to the outer race of the bearing and lock it in place. The outside diameter of the bearing was a very good slip fit into the hand wheel recess, but I wouldn't attempt to use it without the set screw. I have turned wooden pieces to fit the hand wheels of the lathes I have now and made recesses in them to fit the bearing. I have bored and tapped a hole in them to lock the bearing in place. Wood is not the best material to use for that because seasonal movement makes the hole tight at some times of the year and a bit sloppy at other times, but it is what I had available at the time. If I run across some kind of plastic in large enough section I might change it out.

There are actually three holes in the side of the pipe stub; two on one side and one on the other. I have no idea what the third hole is for. I use the two adjacent holes for my retaining bolt and bypass air flow.

Take care
Bob

 

[gregmcateer]

The Nova hand wheel that was on my DVR had a threaded hole for a set screw to snug on to the outer race of the bearing and lock it in place. The outside diameter of the bearing was a very good slip fit into the hand wheel recess, but I wouldn't attempt to use it without the set screw. I have turned wooden pieces to fit the hand wheels of the lathes I have now and made recesses in them to fit the bearing. I have bored and tapped a hole in them to lock the bearing in place. Wood is not the best material to use for that because seasonal movement makes the hole tight at some times of the year and a bit sloppy at other times, but it is what I had available at the time. If I run across some kind of plastic in large enough section I might change it out.

There are actually three holes in the side of the pipe stub; two on one side and one on the other. I have no idea what the third hole is for. I use the two adjacent holes for my retaining bolt and bypass air flow.

Take care
Bob

Bob,

Thanks for the clarification. In your earlier post you said;

"..a short length of 1" O.D. thick walled pipe with one end turned down to a press fit in the inner race of the bearing."

I assume copper plumbing tube up to the job? and where you say "one end turned down", do you mean reduced in diameter to fit the bearing, or do you mean the end is turned over forming a lip at the end of the pipe?

Sorry to be a pain!

Cheers

Greg

 

[Bill Mooney]

Have a word with Simon Hope who should be able to help.

 

[bobham]

Hi, Greg:
I'm sorry, but I have spent the last hour trying to upload some pics and cannot access my web site for some reason. All of your questions are answered in the video liniks I previously provided. The pipe is THICK WALLED so there is enough meat to tap threads. Picture a 1" diameter solid bar with a 1/2" hole bored lengthwise through it. The walls are at least 1/4" thick, so no, copper pipe tubing would not work. One end of the 1" diameter pipe stub is reduced in diameter for a 12 mm length to fit into the 20 mm center hole in the bearing. Here is an old picture of the assembled adaptor:

You will need to watch the video ( https://www.youtube.com/watch?v=3mFl3dxV6xM ) to see it without the bearing installed. I believe it is about the 6 minute mark where I got the old bearing off.

Take care
Bob

 

[gregmcateer]

That's great, Bob. Thanks for the clarification.
Greg

 

[gregmcateer]

Have a word with Simon Hope who should be able to help.

Bill,
Thanks for that
Greg

 

[Woodmonkey]

So I made a vacuum chuck today, it was really easy and only took about an hour and it seems to work great. Here's how I did it if anyone's interested...

I got hold of the bearing linked earlier in this thread by Greg, and a piece of 20mm steel tube from b and q, total cost for both about £12. I cut off about 3" of the tube and it was a nice tight fit into the bearing. I used a vise to press it in there.

I then turned a small piece of wood to round and with a forstner bit in the tailstock I bored out the middle to 20mm. The outside was turned to a slight taper to plug into the end of the vac hose adapter. I could've avoided this step if I could've found some thicker walled steel pipe but I could only find it sold in 3 metre lengths. The wooden sleeve was then epoxied onto the pipe and I drilled a 5mm hole through the wood & pipe as a bleed for the vac to avoid over heating. I will drill another hole through the vac adapter into the wood and put a screw in just to ensure it can't pop out during use. The bearing fits perfectly into the hand wheel on the outboard of the head stock and is secured with a grub screw.

Then I turned a disc of mdf on a face plate and super-glued the rubber to it (from an old mouse mat... don't think she's noticed its gone yet shhh!) A hole through the middle and that's it.

Tried it out on an unfinished fruit bowl that's been waiting for months to be finished and it worked a treat. I could just about pull the bowl off the chuck pulling very hard (probably about as hard as you would to pull it from some cole jaws).

Thanks to everyone who offered help and advice on this, particularly Bob with his very useful videos. 5 Bonus points if you can name the wood.....