taper bearings

Just restoring Acorn/ Halifax lathe and the taper bearing on the spindle is not good. The Price of these timken bearings is silly as could be into £300 for the pair (the lathe is only worth £250). Looks like its due to the outer part having a shoulder. I can get same bearing without a shoulder at much lower price. Is it done to just use inner section and rollers from new bearing with the old outer that has the shoulder. Also can the outer be reground?

Hi Ian,

There is normally only a shoulder on the inner race to locate the rollers and not on the outer race.

I would not like to guarantee what type of fit you would get if you used the old outer race. It may not match the new rollers and is probably worn. Regrinding is probably not an option.

Paul.

Ian,

First ... Welcome to the forum.

Sorry, I am not familiar with the lathe in question, but; if the bearings have external flanges, that suggests that the housings in the headstock may be simply bored straight through.

... is that the case ?

I have seen the component items of some Timken bearings boxed separately, so it may be that you could just replace the inner ... Your chances of this working would be much better if you buy genuine Timken items; because the taper angle is more likely to be an accurate match.

My advice : Check the numbers and ask Timken.

MichaelG.

Edited By Michael Gilligan on 11/12/2014 09:39:07

Is there space with the bearing to turn a couple of collars to act as shoulders. What do the shoulders do?

I usually get my bearings from the Leicester bearing company. I'm in no way connected with them but always found them helpful and extremely well priced. They might be able to help.

Another thought. Is the collar external?

If so then you could make retaining plates and fit them to the castings enabling you to fit  collarless bearings.

Edited By Bodgit Fixit and Run on 11/12/2014 10:08:30

Paul,

I think he is referring to the fact that the outer race has a flange to locate it in the headstock casting.

I guess you could try using a high strength retaining compound to fix the outer races in place but it may be safer to fix retaining collars to the headstock casting. Have a word with Mike Kurn (ex Acorn Machine Tool Co.) he used to, and may still, stock spares and is very helpful. I'll send you a PM with his telephone numbers.

As for the lathe being only worth £250, I think they are very undervalued in the UK. In design it is very much like a 5" version of the Myford. The earliest ones had a poor diecast topslide but later ones were very good.

Russell (Acorn/Atlas owner for 40 years).

It is in your inbox.

Russell

If you can, take the whole bearing to a bearing suppliers, they are in most towns and show them what you want. If it is not in stock they may be able to order it in for you. And it will be a lot cheaper too. I used to work for a company making bearings and they were sold for peanuts really so the wholesaler and retailers could make a good profit. Get an OEM bearing and it could cost you the earth. By the way bodging an old bearing with some new bits is a recipe for disappointment.

I had a friend who worked for SKF bearings in Australia who told me that they gave different discounts to customers, depending on who you are. Big companies who were good customers received a massive discount and mugs off the street who were first time customers were charged full price. Shop around for the best deal.

Paul.

Ian,

Is your headstock the 'interesting' design featured on this page ?

[fourth occurence of the word Timken]

MichaelG.

yes its the 4th and the 14th picture down. I also need the gear to the left of the pully on picture 14 note the locating squares are part of gear not part of pully.

Edited By Ian Lunn 2 on 11/12/2014 21:54:50

.

I think I might be tempted to make a pair of "Top Hat" adapter sleeves ... Same external dimension as the existing bearings, and bored [with a 'stop'] to take a conventional Taper Roller Beaing assembly ... Certainly worth checking what Bore and Outside Diameter combinations are available.

MichaelG.

Edited By Ian Lunn 2 on 11/12/2014 22:07:56

Should never mix bearing assemblies, that was the recommendation ( order), unless things have changed. Maybe more accurate manufacturing will allow mix and match. Cost of bearings- yes wild variations. We used to sell replacement plummer blocks for £4-10s , bought in bulk they were 1s 9p. I have been told that the bearing factors can grind I/D and O/D to make "odd" sizes, I've never followed this up but may be worth enquireing if relevant. Making a sleeve and using standard bearings would seem the way to go.

Another thing to remember is not all bearings are equal, some are high precision, some high speed and others are more of a standard to name a few, the cost can reflect the type of bearing.

.

In recent years there have been some useful variations on the theme of Taper Roller: It would be worth browsing around here for example.

MichaelG.

Hi Guys

Thanks for your input. just wondering if i can get lathe to run with what I have got long enough to make a sleeve. If I want the bearing to be press fit and stay in sleeve how much smaller than the bearing should I make the sleeve and what would be most suitable material?

A light press fit is usually ok for taper roller bearings.

What size are the current bearings, as that may determine if a sleeve is possible as you have to retain the outer bearing half on a shoulder as well as the shoulder for the housing as it has to take thrust loadings.

Bob

Current bearing has od of 69.012mm not including the shoulder This pdf download from Timken is poor on detail so will need to do som measuring for width ect.

Just tryed contacting Mike Kurn who is out at the moment but hopefully will come back to me later today hoping he will have some ready maid salutions.

Anouthe issue is the spindle threads where preload is applyed are not good any ideas if they can be re-cut or repaired in some way I was thinking something on the lines of a bush with new threads on outside smooth on inside and having spindle ground accordingly. This could affect my inner bearing diameter so need to consider this at same time.

Ian,

I just found this 'archive' of notes

There may be something useful in amongst them.

... I suggest you grab a copy in case it disappears.

MichaelG.

.

P.S.  ... a Google search for "60 mm od taper roller bearing" gives loads of results; so that might be a suitable size to consider.

P.P.S ... Sorry, that might have been a little hasty ... many of the hits are for 60 mm id 

Edited By Michael Gilligan on 12/12/2014 16:16:59

Edited By Michael Gilligan on 12/12/2014 16:22:02