Myford ML7

I have a Myford ML7 lathe. It’s week point, imho, is the bushes with drip feed oil.
Has anyone ever replaced the bushes with ball bearings? Is it even possible?

Hi there, Stephen,

Since you mention drip-feed oiling, I assume that you are referring to the white metal headstock bearings.

Those bearings on my ML7 (they are the originals) are doing fine - I bought my ML7 second-hand in 1970!

Best regards,

Swarf, Mostly!

I thought its weak point was wear in the ways? Or was it only the earlier models which did not have hardened ways?

Plain bearings, properly lubricated or not over-speeded, were adequate for the lathe at the time of production. They would have quite possibly consumed more oil (as a total loss system) than a well sealed taper roller bearing set-up, over their lifetime.

Another weak point might be that of driving the carriage with the lead screw. But maybe they were not expecting their lathes to out-live the company.

Many have avoided the weak links, or have replaced the worn parts, over the lifetime of the machines.

They were a good machine at the price-point, which allowed the public to be able to join the model engineering fraternity. They have been used (and still are) to make some superb models, over the years, so the ‘weak points’ have been overcome or avoided by most users.

All lathes are a compromise to some degree. I believe there are modified lathes, with a larger spindle bore, that may have been fitted with alternative bearing systems.

If I remember correctly, there was an article, probably a series, in MEW, which detailed the replacement of the bearings with taper roller ones. I believe it involved some pretty radical machining, but it is doable. Whether it was for an ML7 or a different variant, I can't be sure without further research into the archives.

John

Edited By John Hinkley on 07/05/2022 11:20:18

You would want taper rollers, not balls, in such an application. The only MEW article I recall vaguely is one by Alan Hearsum when he converted an earlier M-Type Drummond/Myford to taper rollers, but it has a one-piece headstock casting which had to be removed and very carefully bored out in a milling machine to take the taper roller races.

The ML7 with removable bearing caps does not really appear to have enough "meat" to machine out for taper roller races. I've looked at it and thought about it, but the OD of taper roller bearings big enough to fit the spindle is too big for the casting to safely accommodate. And again it would be a major undertaking of very precise milling and boring so the spindle ended up parallel to the bed when reinstalled.

The white metal bearings are fine if shims are removed to tighten them up a bit as they wear over many years. But yes they are gawdawful messy. My pet peeve about the ML7 for sure. But not really a weak point. They are a very good chatter-free bearing when set up right. I can take 100 thou deep cuts all day long with mine. But I still hate that oily mess. Just have to live with it I am afraid. At least the bearings always have fresh oil with the total (dead) loss system.

Edited By Hopper on 07/05/2022 11:51:09

But there is this thread on the Myford group where someone did an ML7 roller bearing conversion, mentioning an MEW article by Alan Hearsum in 2014.https://groups.io/g/myfordlathes/topic/replace_ml7_white_metal/69737036?p=

So it looks like it can in fact be done, and has been. But you would need a milling machine to set it up and bore the headstock out.

An added advantage would be that you could then fit a stepped large pulley in the counter shaft and up the top speed to 2000rpm or so for turning smaller diameters with carbide etc. Hmmm. I feel a new project coming on...

Edited By Hopper on 07/05/2022 12:42:48

Edited By Hopper on 07/05/2022 12:46:38

That link in Hopper's reply confirms what I recall. The articles are in MEW issues 210 and 211 and the conversion is, indeed, for an ML7.

John

On my Ml7, I used drip feed oilers from eBay. The originals were dirty with old oil. I set them up so that as soon as the lathe was turned on the slight vibration made the oilers drip.

I also changed the motor to a new 2800 rpm one to double the speed.