Myford lathes help and advice for Bazmak

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I am in the process of restoring a no of Myford lathes.Currently I have a super 7b long bed (I Don't want a long bed)
and a couple of ML7s. I would like to keep a super 7 and gearbox,question are the beds
acorn 01.JPG
interchangeable
Can I swap the long bed on the super7 for a short bed on an ml7 and vice versa.The ways are the same
less wear etc is there anything else I should think about.
Meanwhile I made a few of the beautiful acorn knobs in alum. self colour and satin black
2 sizes the small one just a tad bigger the the Myford plastic one at 20mm dia and the larger one 25mm dia
to possibly replace the round knobs
 
I like your acorns, Bazmak, anything to do with my ballmaker ends up in the scrap bin. Beautiful! Cheers, Peter
 
Hi Barry,
I'd love to read a definitive answer ! I DO know that the beds changed from the narrow guide principle but when is another mystery.
Again, I do know that the headstock castings on the Super 7 Mark 1( which mine is) to the Mark2 is a No No.
Again, if you have access to a shop with a Blanchard type machine, one can - with limits on the degree of actual bed wear 'recondition' a S7 or a ML7 very cheaply. I've done it on both machines in the past.

I wrote that up in Model Engineer decades ago.

So I'm following up the replies like you

Cheers

Norm
 
Of course the 'other' thing or things is the two diameters of the leadscrew- as well as the differences in length.

Years ago, I made up a pair of extended Allen keys primarily for getting into the headstock castings to get at the difficult 4 bolts. Both are 8 inches long- and Imperial!

Apologies, I know that it doesn't answer the question but it does help in what appears the increasingly obvious strip down.

Perhaps Charles can add something as well

Norm
 
Of course the short ml7 leadscrew would have go on the ml7bed which is 5/8" as against the 3/4" leadscrew on the super 7
This would mean changinging swapping the half nuts as well? I know the leadscrew has to be reduced when fitting a qc gearbox
but the 16mm dia end is the same for both.Also the end covers and gears etc would have to go.
So to summarise if I swap a short bed for the long bed I would have to change leadscrews and halfnuts.I think its too
involved and not worth the effort.Will keep this thread open for now
 
Hi Barry,
I'd love to read a definitive answer ! I DO know that the beds changed from the narrow guide principle but when is another mystery.
Again, I do know that the headstock castings on the Super 7 Mark 1( which mine is) to the Mark2 is a No No.
Again, if you have access to a shop with a Blanchard type machine, one can - with limits on the degree of actual bed wear 'recondition' a S7 or a ML7 very cheaply. I've done it on both machines in the past.

I wrote that up in Model Engineer decades ago.

So I'm following up the replies like you

Cheers

Norm
I ought to remember when Myford changed over from the narrow guide system. Way back in the 1960s I had an imperial Super7B which had come out of industry. The bed was worn at the headstock end. I had Myford regrind it but that didn't get rid of the serious design fault with the lopsided front guide faces on the saddle. I milled the inside guide faces away and made a new gib to take up the gap to the back of the bed. I wrote this up in Model Engineer sometime in the early 1970s. Shortly afterwards Myford abandoned the short guide system and followed the method I had adopted.
Several years later I had the opportunity to acquire a later S7 with power cross feed but, unfortunately without the gearbox and the metric version. I swapped the gearbox from my original lathe, modifying the lead screws as necessary. The conversion to imperial was easy as all I had to do was buy new feed screws and nuts from Myford for the cross and top slides as Myford has always fitted 8tpi lead screws. I didn't need to modify the sadle guide system as Myford had already done that.
Other mods I have done are to fit Grorge Thomas vernier dials to the feed screws, fit a Cowells rack feed tail stock attachment, fit a Lavis vernier hand wheel to the saddle and, best mod of all, replace the pair of angular contact bearings at the tail of the mandrel with a pair of taper roller bearings. At the same time I replaced the useless oil nipple on top of the rear bearing housing with s simple oiler filled with wadding. Both belts are now nuTee link belts and the lathe is driven by a 1HP 3-phase 2,400 rpm motor through an inverter to give smother running and speed control. I regularly run at 2,500 rpm and have had it up to over 4,500rpm!
DickG
 
Thanks Dick on your informed comments With a simple answer do you think its feasible to
swap a long bed on a super 7 with a short bed from an ML7.I think the leadscrew will be the
main problem as that has to transfer with the bed.Could everything else be transfered
Ie headstock, countershaft ,guards and carriage etc. Could the 5/8 and 3/4 halfnuts be
transferred with the leadscrews.Its making my headspin wondering if its worth the effort
May try to find a Super 7 shortbed without gearbox and do a swap.I want to finish with a shortbed super 7b
 
Dick, would you explain the reasons for fitting the taper rollers?
With the earlier S7B I had it was easy to adjust the rear bearings and then set the front bearing clearance. I had no problems with running at top speed or putting a large drill into steel. With the later model I found it impossible to set the rear bearings and they wouldn't take any end thrust without locking up the front taper bearing. I tried several new bearings from different makers including spending a large chunk of my pension on genuine Myford ones. Replacing the rear angular contact bearings with a pair of taper roller ones completely solved the problem. Another local model engineer also had the same problems, again solved by the taper roller mod. I have attached a pic of my rear bearing oiler. The original article was by Ken Willson in Model Engineers Workshop April 2011 with some important corrections that I suggested later after I had modded my lathe..
 

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    Myford S7 Rear Bearing Oiler 01.JPG
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Thanks Dick on your informed comments With a simple answer do you think its feasible to
swap a long bed on a super 7 with a short bed from an ML7.I think the leadscrew will be the
main problem as that has to transfer with the bed.Could everything else be transfered
Ie headstock, countershaft ,guards and carriage etc. Could the 5/8 and 3/4 halfnuts be
transferred with the leadscrews.Its making my headspin wondering if its worth the effort
May try to find a Super 7 shortbed without gearbox and do a swap.I want to finish with a shortbed super 7b
 
I don't know about transferring an S7 onto an ML7 bed. One thing that won't transfer is the serial number stamped on the bed! I don't understand why you want to change to a short bed. Is it because the long bed won'f fit on your stand? If that's the problem wouldn't it be easier and cheaper to acquire a new stand? Don't forget that the S7 leadscrew changed when Myford introduced power crossfeed - acquired a longitudinal slot to drive the crossfeed gear. The change from narrow guide to broad guide was in August 1972. Useful info - parts lists, serial numbers, etc. - can be found on: https://www.myford.co.uk/acatalog/A-History-Of-The-Super-7-887.html . I have discovered that the bed for an ML7 has the same Myford part number (A8724) as the bed for a Super7! So you should be able to interchange them.
 
Thanks Dick.I was of a mind that the bed would be compatable but the leadscrew would give me problems
and as you say I would stuff up the serial no. I think I will wait and hopefully get a short bed super7
Yes in answer to your question,i have very limited space and I found the long bed too heavy to handle on my own
Thanks for your input regards barry
 
I'd make the effort to accommodate the longer bed. It's the kind of thing you don't really need, until the day you need it, and then you really need it. Also, on a daily basis it's real handy to be able to park the tailstock well out of the way when out of use.
 
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