Dreadful Shrieking from the old gal.

[DanClarke]

She's making a terrible racket (the lathe, not the missus).
It's a 66 YO Boxford AUD
It seems to be coming from the intermediate shaft pulley stack.
The stack spins on the shaft that is bolted to either side of the cabinet.
Adding oil through the button-oiler oiler on the end of the pulley stack is not really improving matters, but the oil is managing to get spread in a vertical line up the back of the cabinet.
I guess whatever bearings there are/were in there are now shot.
I have not taken the shaft out ever, but I cannot find any AUD clips on YouTube with the same earlier mechanism as mine to glean any hints & tips from.
Does anyone know what type of bearing I am likely to find in there and if they are still available?

TIA. Dan.

 

[RWD3M]

It's not just a belt slipping is it Like a fan belt does on a car?

 

[dave h 2]

I take it you have found the lathes.co site? It's where this came from.
They look to be Plummer blocks

 

[DanClarke]

I take it you have found the lathes.co site? It's where this came from.
They look to be Plummer blocks

View attachment 480425

Thanks Dave. Sadly, mine is the earlier version with the pulley stack spinning on a stationary shaft. No plummer blocks.
The shaft ends are bolted to the opposite sides (L & R) of the cabinet. It's just the pulley stack that "spins". That lter arrangement is much more sensible indeed.

Mine is as per the drive systems page on Lathes.co.uk
"Early under-drive lathes had their countershaft-spindle bushes pressed directly into the material of the motor platform itself, with the belt-tensioning handle mounted externally on the left-hand side of the cabinet. With the handle so temptingly placed many owners were inclined to use it as an unofficial (and dangerous) substitute for a clutch."

"In 1960 the countershaft was modified: the shaft diameter was increased to 0.75" and, in 1966, further improved when the shaft was increased to 1-inch diameter, the bearings fitted to removable brackets, the belt-tensioning lever repositioned within the cabinet base and the access door (like the educational versions) provided with a micro-switch that stopped the motor should it be opened by even a fraction of an inch."

 

[DanClarke]

It's not just a belt slipping is it Like a fan belt does on a car?

Sadly not.

 

[DanClarke]

Thanks everyone.
I am going to take it all apart this week (weather permitting, because I have to sit on the concrete floor with the garage door open).
Pictures of the "as-is" and pulled out assembly will be posted, It might be a simple job. we shall see.
I am sure it will be fixable, I cannot imagine Boxford's did not foresee a need to replace the bearings.

Dan.

 

[Seadog]

They're a standard ball race. A right pain to do, though. If you've the original V-belts fitted it may be time to invest in some link-type belting.

 

[DanClarke]

They're a standard ball race. A right pain to do, though. If you've the original V-belts fitted it may be time to invest in some link-type belting.

An ache in the ballrace eh? V-Belts were all changed last year, so should be good for my remaining lifetime. The headstock T-Link belt is slipping a bit (I can stop the lathe with applied hand pressure on the headstock) and I have a new one of those, so It might be a good time to change that while I am in there.
It is a lovely old lathe 60+ years the only thing I would change is the topslide for one with with multiple T-slots like on a Myford.

 

[Seadog]

Indeed.
The belt is probably slipping because it's under-tensioned. The Nu-T-Link belt tensioning instructions make for interesting reading.
I replaced the in-cabinet assembly in my 1962 model for the later assembly, and also removed the counter-shaft. I have no problems running the machine since fitting a 3-phase motor (1hp) and a vfd.

 

[DanClarke]

This layshaft arrangement is different from any other Boxfords that I have seen described on lathes.co.uk. Completely different I think.
I removed the whole assembly from inside the motor cabinet (6 bolts).
This is what it looks like. A non-rotating shaft fixed in position at either end and a pulley stack with bronze top-hat bushes pressed into either end.
This is all held in horizontal alignment on the shaft by two collars.

I removed the collars and took the pulley stack and bearing bushes off the shaft.
There are few marks/nicks in the shaft but nothing serious.

Similarly, when you examine the bronze bushes they feel smooth and regular. The pulley stack when placed back on the shaft spins quite freely (but it is not loaded at this point of course).
Looking into the pulley stack you can see the bearing surface looks OK (ok to me).

It is interesting to note that none of the oil placed into the pulley assembly through its button-oiler can get directly to the bushes unless you fill the space completely with oil up to the level where the axle-shaft is.
I cannot see anything terribly wrong with it all and I am going to reassemble it all and fill that cavity with a decent amount of oil.
Worst-case, I have to pull it all out again and have another go or get some bushes made.

 

[DanClarke]

Indeed.
The belt is probably slipping because it's under-tensioned. The Nu-T-Link belt tensioning instructions make for interesting reading.
I replaced the in-cabinet assembly in my 1962 model for the later assembly, and also removed the counter-shaft. I have no problems running the machine since fitting a 3-phase motor (1hp) and a vfd.

I have just cut the old T-link out (too difficult to undo it). The new one feels extremely stiff and difficult. I have a bad feeling about this.
I have re-read my dictionary of anglo Saxon curse-words in preparation for the fight to get the ruddy thing tensioned.

 

[DanClarke]

check the bushes for ovality

I will try. When put back on the shaft there is no "slop" or rocking in any direction that I can feel/see/hear. I don't have any bore gauges, so a crude check with a digital vernier will have to do.
Does ovality taste like Ovaltine I wonder?

 

[RWD3M]

They're oilite bushes so impregnated with oil, heating a pan of SAE oil and soaking can help impregnate new oil into them

If you need to replace them, most bearing people stock a pretty good range. IIRC I used bearingboys.co.uk for new bushes (all imperial) for the gearbox in my '36 Morris.

 

[DanClarke]

They're oilite bushes so impregnated with oil, heating a pan of SAE oil and soaking can help impregnate new oil into them

I find it interesting that there is a button-oiler on the pulley-stack shell that discharges oil into the internal void where "if" you put enough oil IN then it will eventually reach the bushes and keep them "wet".
However, if the button-oiler leaks-back then it throws this oil all around the cabinet in a nice straight line on front/back/top/bottom.