Hot bearing?

I am sure I am not the first in being anxious and possibly paranoid in worrying over maintenance issues on my newly acquired lathe...

Anyway adding to my worries that I didn't know when the bearings were last greased (or which ones should only be oiled), I discovered that the rear headstock mandril bearing was getting hot to touch. The front headstock bearing was cool.

Is it possible that I have over greased? If so what can I do about it?

Lathe make?

myford speed 10, sorry should have said.

Hi John

With My very limited knowledge is thatThe Myford Speed 10 has taper roller bearings.

Is the preload on the Taper Roller Bearings set correctly.

On a used machine with overheated bearings is most probably over greasing.

A quick dismantle of the of the rear bearing with the inner race removed, cleaned, inspected the inner race for any damage. Reassemble with fresh grease not more than 1/4 of the total bearing housing.

Reset the bearing preload after running and allowed to cool down to room temprature.

Afterthought edit! When a new bearing is fitted they will often run hot when run at high speed until they are "run in" 

Eric

Edited By oldvelo on 15/08/2020 00:59:38

I suspect over-greasing too. Gets hot because excess grease is churned inside the bearing, too much grease is like glue. The bearing's been turned into a brake.

I'm not familiar with Speed 10 bearings so this might be rubbish advice. If the grease has any way of escaping from the bearing, simply running the lathe gently will tend to clear the excess. Otherwise, see Eric's advice. Any Speed 10 owners out there who know the answer?

Note to beginners keen to start with a deep clean! As Jon's been 'at it', now difficult to tell the difference between a dud bearing needing attention, and a good bearing temporarily smothered by love! Modern machines are usually robust in this department because they come with sealed for life bearings. Older machines are more challenging because a number of different lubrication options are possible - more booby traps! Total loss oil, pressurised oil, or oil and/or grease scheduled maintenance requirements all benefit from being understood. Not rocket science, but definitely a good idea to read the manual. On the plus side, it's unlikely Jon has done any permanent damage. It's possible the bearing is getting hot because it's knackered, not because Jon overgreased it, in which case fit new bearing!

Dave

I think I will run the lathe up at moderate speed without load and see if the rear bearing throws off the excess grease, perhaps do this a few times if it gets hot.

Personally I dont wish to take the mandril out at this stage, I will wait until the v belt needs replacing.

By the way are there any re-joinable v belts and would anyone recommend them?

Years ago, when i worked for BR we had problem with bearing over heating and it turned be to be over greasing. The operatives were filling the bearing FULL no space for expansion and when things got warm and hot the seals leaked badly, then the bearings failed. An very expensive job to change bogie wheel bearings..

Fenner (Hull) make link belting, which is tricky to join up, you have to be persistent. I've got Fenner link belting fitted to my drill and mill .Also there used to be Brammer of Bradford ,not heard of them for a long time. the factory site is probably a housing /trading estate by now.

Pull the grease nipple out before you run it so there is somewhere for excess grease to get out maybe.

Thanks I will do that.

My ML10  gets 1 push of the grease gun a YEAR, no excess grease appears at all. LM something grease is fine.

Edited By Clive Hartland on 15/08/2020 13:41:39

I greased up the primary pulley when I think it should take oil, is it a problem or can I get away with it?

I found this information about the Speed 10 spindle:

**LINK**