Thread: New / Old Lathe Headstock Issue

In the lower right there is a link to the Nova Comet II parts schematic - check that item 22 the internal circlip is there.

Manual is lower left - page 22 explains removing spindle.

NOVA Comet II midi lathe : Teknatool International (freshdesk.com)

Big question is - is your Comet the same?

Given the moulding it doesn't look like it, but... if you remove the pulley, can you see bolt-holes anywhere for some form of retaining plate? Or possibly something like a circ-clip to hold the bearing in?

Thanks for putting this forward Mobyturns.. Unfortunately my shaft doesnt have the slot for a circlip or the ability to get to shaft while its in the headstock to put one one

Thanks Skew, Under the pulley is a position to tighten the grub screw in the pulley to hold it in place. Unfortunately it moves with the shaft when the bearing moves.

The groove for the circlip is not in the shaft but in the housing. It holds the bearing in the housing and the shaft pushes against it.

Do both bearings move when pressure is applied or is it just the shaft and the rear bearing? If it's just the shaft and rear bearing it seems like there might be an incorrect shaft in there as the sketch attached shows the shaft with a larger diameter flange sitting against the bearing and yours doesn't appear to have that.
If it's the shaft and both bearings then the circlip behind the front bearing is missing. If there doesn't appear to be a groove for the circlip to locate in then maybe the previous owner tried to knock the bearing out without removing the circlip, in which case they possibly broke the edge of the circlip groove off.

Headstock.JPG

Thanks Bohdan, I dont recall seeing a groove when I cleaned out the housing before I put the bearing back in but I will double check. I felt a slight glimmer of hope once I read your suggestion... I also see from looking at a few lathe manuals at work during my break today that this seems fairly standard, Perhaps I missed the groove... I will get a chance to check in Wed or Thurs after work. Fingers crossed its something simple like that.

Thanks Treecycle, both bearings move or at least the shaft moves on the first bearing and the second bearing moves due to the way it is housed on the spindle.

The diagram you showed looks like how the spindle should be. I hope to hear back from Technatool to see if they have a copy of a manual but I am not confident..

I will put it apart over the next few days and take another look now that I have a bit more knowledge.

I appreciate you and all of the other member taking the time to reply.

Originally Posted by Backyard Shed

Thanks Treecycle, both bearings move or at least the shaft moves on the first bearing and the second bearing moves due to the way it is housed on the spindle.

The diagram you showed looks like how the spindle should be. I hope to hear back from Technatool to see if they have a copy of a manual but I am not confident..

I will put it apart over the next few days and take another look now that I have a bit more knowledge.

I appreciate you and all of the other member taking the time to reply.

Don't rely on "customer service" from Teknatool, there ain't any. I had the variable speed unit go on my Nova Mercury several years back, and their response was its "an old lathe, we don't offer parts support." It was less than 6 years old at the time. Trend Timbers were more helpful but were in the middle of a relocation and due to that couldn't locate & access the two that their system said were in stock. They did follow up with me after the shift but could not locate the units. Try them, at least they offer service.

When I posted the Comet II info I knew that the headstock castings / designs were quite different, however designers are creatures of habit and tend to use similar designs on the fundamentals.

Contact Jim Carroll at CWS in VIC. Jim is a knowledgeable & helpful bloke, plus they sold Teknatool in the past. Also a sponsor of the forum.

This is the only picture I can find of that model and the headstock spindle looks the same as what you have without the flange so it appears there must be something missing inside. The diagram posted earlier is for a Nova 2 I now see which has a different design.

Spindle_2.JPG

The Nova 1624 has a similar head stock design, in the parts schematic (p27) look at items 38 & 45. There must be a circlip retainer to act as a thrust stop. I would suggest that item 45 - the Circlip External 72mm or its equivalent on the Comet 1 is missing.

NOVA-1624-Manual_June-2016_FINAL.pdf (teknatool.com)

That design is common across the TL1200, TL1500, 1624 etc so it is reasonable to assume the original Comet will share that lineage.

I agree, I think item 45 is the missing link.

Thanks for the replies.

It is correct to say that Technatool wouldn't be of any help. There reply was brutal.... We stopped supporting that model long ago.. Try google...

Only just getting home from work now so cant get to pull the lathe apart again just yet.

I really appreciate the knowledge shared with this. I have had mixed experiences with things like this so didnt know what to expect when i posted this issue.

I agree there must be a circlip at the rear if that's what the other older models have. When I pull it out I will take another look but it didn't feel or see a groove then i clean it it with a cloth before putting the bearing back in last time.

Seeing the photo was super helpful, I though I looked far and wide and couldn't find one. It rules out a lock not or similar missing from the front which was my bet.

I just got back from pulling the spindle and bearing out again.
Unfortunately, it wasn't as I thought and was hoping for. I will put this up incase someone comes across this thread at a later date as has the same issue.
There ins't a groove for a circlip on the rear or front housing. When the rear bearing sits all the way home at actually protrudes slightly from the housing so that double rules out a retainer of some sort at that end.
There is also no groove for a circlip on the spindle anywhere. The blue arrow in the picture shows where the bearing sits on the spindle and the groove where the other arrow is shows a groove for the pulley grub screw to sit.

Obviously, something is wrong somewhere but I dont think I am going to get an accurate answer anytime soon.

I am going to try a lock nut and a washer at the front end. I have a milling machine so I will make it as thin as i can so I leave enough thread for a chuck or faceplate. Fingers crossed that gets it going!!

Front bearing housing.jpgRear bearing housing.jpgSpindle.jpg