making new lathe spindle

For reference: Here is a typical 1" bore taper roller bearing.

Outer diameter is too large ... although I believe there are also 'slim' versions available for things like motorcyle headtocks, so all may not be lost.

Alternatively, consider my Plan_B instead.

MichaelG.

Graeme,

Our last posts crossed in the æther

If the bore is as good as you think, then please ignore my previous suggestions ... it should be quite possible to plate and grind the spindle.

MichaelG.

Edited By Graeme Whitfield on 23/02/2015 22:55:12

I don't think it would need a heavy preload, but I do think it's important for the headstock housing to be stable & rigid to resist loading which would now be borne mainly by the front bearing. I just wonder if that design could possibly move far enough under load to allow the rear bearing to 'disconnect' from its race.

Most taper bearing assemblies are within tubular or box shaped housings for rigidity I think.

Martin.

Here is the spindle, its just the larger area that is worn.

Options are, try and make a new one.

Get it ground and plated.

Get it turned down and sleeved.

I have no idea, but my gut feeling is sleeved would be cheaper to get done than plated?

.

This style is usefully a litle smaller.

But re-working the spindle definitely looks like the easy option.

MichaelG.

Edited By Michael Gilligan on 23/02/2015 23:13:53

Cant add a link, but bicycle ones in 40mm internal are only 52mm external and 7mm wide.

It's probably all moot anyway if going the plate/grind route, but if considering rolling bearings, is there a reason the preload must necessarily 'bridge' the two headstock ends? Far better surely to have two bearings in the 'working' end back to back, preloaded against each other, plus a 'floating' bearing at the other end. Rather as per Figure 2 here.

Edited By Bikepete on 24/02/2015 16:55:58

It doesn't look like there is an easy way to accommodate adjustment of preload in the OPs Drummond lathe by using design No2 of your link, but I thought something similar to design No4 would have been the most likely candidate to stand a chance of success given the existing layout.

Martin.

That is a lovely little lathe and I think worth the effort to bring her back to life.

I would have the spindle machined/plated/ground or see if there are any local machine shops that have thermal metal spraying capability such as High Velocity Oxygen Fuel. It can often be less expensive than chroming.

I would then have the head stock line-bored for the appropriate bushings instead of tapered roller bearings.

Hans

Fig. 4 is the bearing arrangement on many small lathes, notable mini lathes and on the X-series mills.

Taper rollers typically need very little preload.

Neil

At least you have got a sprindle and bearings. My first lathe, a very old Drummond, came with the bare headstock, the seller saying that it would be an easy task for a professional turner to make and fit the missing bits. Anyway, I made them myself. I will not go into detail but the bearings were tapered in the headstock and as I did not have any bronze of a suitable diameter, these were turned from steel and bored out to take bronze sleeves. These were shrink fitted and reamed before splitting. This setup lasted me for many years and was a great introduction to the hobby.

Your lathe looks great and I hope you have as much joy as I had with your first projects.

Graeme,

Are they going to bore the headstock for some bushings?

By all means polish the steel and iron surfaces that are intended to be left bare... and if it were me.... I would paint it black as that is the fitting colour for this era.

https://www.youtube.com/watch?v=Gs1SOu7APnU

Hans

Posted by Graeme Whitfield on 25/02/2015 12:28:02:

I went to second precision grinders today, one of tje many benefits of being in sheffield is there are LOTS of engineering firms, they were friendly and knowledgable. Quoted me ?60 so I left it with them. I think they took pity on me
Left them the headstock too do they can fit the spindle to the bore.

.

Excellent news, Graeme

MichaelG.

.

P.S. "I think they took pity on me" ... Did you take that dog do the soft-eyed look for you ?

Edited By Michael Gilligan on 25/02/2015 14:44:20

Edited By Graeme Whitfield on 25/02/2015 14:58:12