Ball Bearing Advice Please

Afternoon All,,

I am refurbishing a Tom Senior Vertical Light mill. The bearings in the traverse (hope that's the right word) are worn as are the cages they sit in (see attached).

I think I can find replacement balls but the cages might harder to come by. Could I get away with just replacing the balls?

A couple of emails have gone off to two bearing suppliers but I have little hope of them being interested in such a small order.

Any advice would be very welcome.

Regards, Nick

Nick,

Welcome aboard !!

Is this a thrust bearing; working between two flat [or grooved] washers ?

... If so, then I suspect that there will be a modern alternative readily available.

Could you please provide some dimensions.

MichaelG.

.

P.S. ... You may find this useful.

Edited By Michael Gilligan on 28/07/2015 17:56:21

Not seen a thrust bearing like that before but as Michael says perhaps a modern alternative will do the job. If not then try just replacing the balls as suggested.

Ask ArcEuroTrade. The will probably be able to point you in the right direction.

Push Bike practice on the handle bar head bearings. Great fun when the nut comes loose and you loose most of the balls.

Hi Nick,

As mentioned above it is a thrust bearing and there will or should be two end discs with a groove ground in one face that the balls ride in .

You will need outside diameter , inside diameter and total thickness of the bearing with the two discs fitted to allow the bearing supplier to find what you need .

You mentioned that they are worn ?

How have you determined this ? As they are not something i would have suspected to be worn out , if the balls are still running smoothly in their grooves they are probably ok - look for any corrugating in the end disc groove and check the balls out if there is no apparent damage all is good .

Ian

I replaced the thrust bearings in my Tom Senior Junior Y and X Axis handwheel/leadscrews. I don't know whether the sizes are the same for the light vertical.

For my mill they were FT5/8 Imperial Thrust Bearings and come with the balls/cage assembly and two races to run in.

A word of caution, I bought some unbranded ones and they should have been 0.281" thick, but mine measured 0.286" thick. Because of the way the Y axis bearing housing was designed, they are not adjustable, so the unbranded bearings were binding when tightened down. I had two options, shim out the bearing housing with the oversized bearing, or return them and get branded. I ended up returning them, and the vendor replaced them with branded RJH variants which fitted perfectly with no shimming required. Vendor was Bolton Bearings.

Hope this helps

Graham

Thank you all for the prompt response - I do have that manual thank you Michael.

The bearings sit between to flat shims which are about 1mm thick. They do not have machined grooves in them but there is some surface pitting. I have already worked out that these could be reversed if needs be to provide a decent surface for the balls to run against. Some of the balls are pitted which is why I said they are worn. I get the impression that the oiling point on the traverse may have become blocked.

A quick Google yesterday showed a similar product that is called a thrust bearing and with similar cages.

Dimensions are: Outside diameter 32.75mm and inside diameter (the hole) is 19.30mm. As I said earlier I am pretty sure that this mill is mainly imperial unlike my 1978 Boxford lathe which is a real hybrid of Whitworth & metric.

Thank you all once again for your help which is much appreciated.

Regards, Nick

PS: Graham - just seen your post.

Edited By Nick Thorpe on 28/07/2015 19:05:22

Edited By Nick Thorpe on 28/07/2015 19:05:45

Nick,

I suspect the bearings you need are FT3/4 bearings. They are pretty readily available for less than a tenner.

They should have O/D of 33.35mm (1.313" ) and I/D of 19.05mm (3/4" ) and thickness of 7.14mm (0.281" )

Graham

Edited By Graham Wharton on 29/07/2015 11:37:27

Edited By Graham Wharton on 29/07/2015 11:37:46

Graham,

Thank you for your help. I had to work late last night but measured up the bearings this morning and Bolton Bearings seem to have them.

Regards, Nick

Simply Bearings have no minimum order and a very extensive stock of name bearings both imperial and metric, their sales team are also very helpful even if you only want the one.

No worries Nick. I had a look at the drawings for the Tom Senior M1 mill, and it looks like handwheel/thrust bearing design is the same on the Y axis screw as it is on the smaller Junior mill that I have. The only difference being the size of the bearing. Therefore the thickness of the bearings is critical to avoid shimming out the bearing housing.

Bolton bearings were great in resolving the problems I had. They measured the remaining unbranded bearings that they had in stock and these showed to be out of spec too which is why they ended up sending me branded instead. Thickness wasnt critical for the X screw, which I just used some of the out of spec unbranded bearings for.

Might be worth trying Simply or Arc. I've had great service from all three to be honest.