Myford ML4 ?

[Brian WoodParticipant @brianwood45127]

Hello Mike,

Just click on my photos, it is the second one in the list below the ML 7 gearing table

Your 163 sounds like the serial number, clearly an early one, but I can't remember what the grub screws you refer to did or why they are where they are. Best left alone I think

Brian

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Brian Wood on 27/08/2016 19:41:59:

Just click on my photos, it is the second one in the list below the ML 7 gearing table

.

Only one image in that album, Brian

Useful diagram, but I presume that Mike was expecting to find all pages of the manual.

MichaelG.

[Andy AshParticipant @andyash24902]

I don't think your topslide is original, so I can't say what your grub screws do. It appears to have the ML7 dials by the look and these didn't come along for a good few years after the machine was made.

It's probably not a bad thing, the original had 12tpi screws, which are a little like a chocolate teapot.

I remember writing to real Myford back in the eighties when I got mine (as a teenager). I asked for a manual, but they said there wasn't one. The sent me a photocopy of the picture (IIRC) linked on Brian's profile. It was pretty grainy. Then at the bottom of the A4 sheet was the original screw cutting chart for the change wheels.

I don't know what I did with it. But it's long gone now.

Edited By Andy Ash on 27/08/2016 20:11:16

[sparky mikeParticipant @sparkymike]

I found a simple manual for the early 3 1/4" and 3 1/2" Myford on the site below.

http://vintagemachinery.org/pubs/detail.aspx?id=6592

However, when I saved the pdf, the first half only shows the top of the pages, while the second half is normal size ??? Strange

On the site it is possible to view the pdf and then all pages are correct size.

Mike.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by sparky mike on 28/08/2016 07:21:50:

However, when I saved the pdf, the first half only shows the top of the pages, while the second half is normal size ??? Strange

.

Mike,

It seems to have saved O.K. on my iPad

Suggest you try again … Yours may just be a corrupted download.

Happy to send you the PDF by eMail if you're still having trouble.

… Send me your address by 'Personal Message'

MichaelG.

[Andy AshParticipant @andyash24902]

That link is superb.

The A4 sheet that Myford sent me was obviously taken from that information.

It was the picture at the beginning and the Whitworth / Metric screw-cutting table in the middle.

I imagine they didn't send me the descriptions and part numbers so I didn't try to make an order!!!

I don't know if it helps, but you should find that the standard Myford vertical slide will fit on the machine.

In some ways the ML4 is better with the vertical slide then the ML / Super 7. The dovetail bed is better at dealing with forces upwards and away from the bed. Obviously the vertical shears on the seven rely on the retaining plates and the accuracy of the shims for upwards forces.

I remember being quite disappointed about that last point when I got my Super 7.

Edited By Andy Ash on 28/08/2016 10:55:56

[Brian WoodParticipant @brianwood45127]

Mike,

My apologies, it seems as Michael G says that I have only put the annotated photo in my album.

Until I get the current problem I am having sorted out by shifting my browsing onto Chrome, the best I can offer you for a copy of the full handbook is to get in touch with me by email​

It is as Andy Ash said, the feed screws for cross and top slide were both made as square form 12 tpi threads, but Myford fitted calibration collars having 80 divisions so that each division corresponded to 0.00104 inches of tool movement. It didn't of course get over the fact that one full turn moved the tool by 0.083 inches, a particularly difficult number to work with. Furthermore, the 12 tpi 'nuts' were made directly into the casting I seem to remember, it was only when they started making the ML 7 that separate feed nuts were introduced.

The Bull wheel is 65 teeth, another awkward number for division purposes and the teeth are very ​ prone to chipping, I have one in for repair now with three broken off teeth.

One modification I found really useful was to convert the mandrel to ML7 specification by adding a collar to the nose and machining a new register diameter of 1.250 inches on it in situ using the longest reach tooling I had to get there. After that of course, all standard ML7 spindle fitting hardware could be used. Even then, finding such equipment with the ML4 register of 1.125 inches diameter was uncommon and it will be harder still today.

My email address is wood_y (at) btinternet (dot) com all in lower case, no spaces and with an underscore between the d and y

I had 30 years use after inheriting Pop's old lathe and cut my teeth on in from the aged of 7.

The real design failure was with the tailstock setting and that dreadful arrangement on the soleplate, but I found ways of getting round that too which I will happily share

Regards

Brian

[sparky mikeParticipant @sparkymike]

Hi Andy re. " I found two small grub screws next to each bearing on the top side. Do these locate the shell bearings, to stop them rotating ? " I was refering to top side of heas stock, not top slide. ( I should have been more explicit. )

The dial indicators on the cross slide etc. have 0 to 100 divisions, but I have not as yet checked the TPI of the lead screws, to see if they were modified at some time in the past.

There is a small bronze bracket at the front edge of the cross slide, held on with two 1/8" diam. screws. I am assuming that this is where a dial indicator was attached ,as there is a semi circular cut-out in the lead screw guard at about the same location..

This lathe, which I finally now think is a ML4 ,has a centre height of 3.5" and between centres it is just under 24".

At the gap it could swing just under 10" diameter item which I know from my old Drummond is pretty handy at times.

Mike.

[Andy AshParticipant @andyash24902]

I think I know the holes you mean.

I don't think I ever had any screws fitted in there. One hole is full of paint.

The other is clear to the bottom, and I can see the shell, and then a hole through to the spindle.

If you rotate the spindle you can see it moving at the bottom of the hole.

The nearby oil holes look to be much the same if you remove the oiler.

Hope it helps.

Andy.

[sparky mikeParticipant @sparkymike]

I have now had a chance to check the cross-slide threads and they are both 10 TPI which makes for easy setting.

One full turn of the handle is 0.100" and 10 turns is 1.000"

I have found a couple of Myford drawings which help to clarify the differences between the ML 1/2/3 and 4 models and they are in one of my albums.

Mike.

[Neil WyattModerator @neilwyatt]

If you visit the Lathes.co.uk website you'll see the bronze bearings are bored in place; don't do anything to disturb them, and if they need replacement you will need a way to accurately bore new ones in place. Beware over-tightening as the casting may crack.

Neil

[Andy AshParticipant @andyash24902]

That last point from Neil is really critical.

Those pinch bolts are easy to abuse. Once abused, it's really hard to get it back again.

I apologise for not being very attentive, I've been a little busy this weekend.

I recently had a fair bit of dialogue with Wayne from Staffs. A whole load of ML4 type stuff (including the pinch bolts) came up. You might find that thread interesting……

**LINK**

Edited By Andy Ash on 29/08/2016 11:04:55

[Brian WoodParticipant @brianwood45127]

Neil and Andy,

​I have made the same point with Mike in private contact, but for others the risk can be prevented by fitting closely sized shims with location holes through them so that the bolts close down onto solid material.

Regards

Brian

 

Edited By Brian Wood on 29/08/2016 11:29:08

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Brian Wood on 29/08/2016 11:28:52:

… the risk can be prevented by fitting closely sized shims with location holes through them so that the bolts close down onto solid material.

.

I doubt if it's original to these lathes, but;the mullti-layer 'ShimPack' material would seem a good candidate for this job.

http://www.shimpack.com/shimlammetals.html

MichaelG.

Edited By Michael Gilligan on 29/08/2016 11:59:25

[sparky mikeParticipant @sparkymike]

I just removed the rack from the bed and a bit curious about this. I would have expected to see machined areas behind each of the six screws positions on the bed, but it all looks like rough casting.

There are oversized washers between the rack and the bed. problem with those, is that the rack pinion meshes hard against them at each screw location. Took me a while to figure out what was happening as I first thought that the rack had swarf imbedded in the teeth. Anyone else had this problem ?

Mike.

[Brian WoodParticipant @brianwood45127]

Mike,

​I never disturbed the rack fitted on my lathe, but like you I would expect machined seats. Rather unlike Myford to skimp that, more akin to cheap Chinese practice.

​Brian.

[sparky mikeParticipant @sparkymike]

I decided to run a concentricity check on the lathe before I go any further. The face plate was on the spindle, so with the aid of magnetic base and dial gauge I rn a check on the turned outer edge and was a bit dismayed to find it was running out by around 0.005". I then ran a nother check on the face plate machined face near the outer edge and that too was around .005. I removed the faceplate and cleaned the mating surfaces on both rear of faceplate and the spindle nose with similar results.

I then removed the face plate and checked the spindle nose and it is within 0.0005".

I probably have a test bar that I can try between centres, but at the moment I am reasonable happy with the headstock.

Question is this, do face plates suffer from that kind of run-out generally ,or is my faceplate possibly from a different lathe and should it have been faced up on my lathe before use ?

Mike.

[sparky mikeParticipant @sparkymike]

I should have added that I checked the spindle nose in both planes.ie edge and face. I found that I could get around 0.002" fore and aft movement by pressing on the pinion end of the spindle.

Mike,

[Brian WoodParticipant @brianwood45127]

Hello Mike,

​That is rather more than you should have. There will be a screwed collar on the spindle just inboard of the 25T gear; that is what is used to set spindle end float. It should have a grip screw nipping the screw thread below via a slug of copper shim to prevent crushing the threads, they are quite fine pitch.

Take out the slack until there is just discernible resistance to rotational movement of the spindle. The thrust bearing is a plain flat contact open ball race bearing on two hardened washers just behind the rear of the chuck location register and buried inside the bearing housing .

Regards Brian

[sparky mikeParticipant @sparkymike]

Hi Brian,

Adjusted the collar and now no end float.

However, I am now wondering if the headstock spindle has a very slight bend in it.

I will not know for sure until I strip the headstock and check the spindle on V blocks. I tried a test bar in the headstock morse taper (no. 2) and at a distance of around four inches from the spindle front shoulder, I get around 0.005" out of centre.

Mike.

[BazyleParticipant @bazyle]

note: check endfloat when at operating temperature.

[Brian WoodParticipant @brianwood45127]

Hello Mike,

​That is not a definitive test for the running truth of a spindle. It is much more likely to be a tiny burr raised in the taper, or even a small particle of dirt. Your earlier test of the chuck mounting register didn't show more than tenths.

Try cleaning it out, feel inside with your little finger, spindle rotating slowly, and make sure the 2 MT mail part on the test bar actually seats in the socket.

On my father's lathe he must have caught it at some time with a boring bar. I cleared that with a surplus 2 MT drill shank and the merest trace of fine valve grinding paste. The lathe was run slowly and I held the tool by hand. After thorough cleaning, the error was about 1/2 thou at 6 inches. It had been worse than the figure you report. Of damage to the socket there appeared to be none and the tool was still perfectly satisfactory afterwards.

I also endorse what Bazyle says about operating temperatures and be prepared to ease the setting you have achieved if the slightest tightness shows up. The best test is to feel the bearing housings with your finger tips

Regards Brian

[sparky mikeParticipant @sparkymike]

Hi Brian and Bayzle, I understand the end float adjustment and hit this problem with my first Drummond, way back when and also have a very similar adjustment on my Boxford. You soon know if it is too tight !!

I ran another test after cleaning the taper with a no. 2 morse taper reamer by carefully rotating it by hand with no pressure on the oiled reamer and now I get 0.002 around 4" from the spindle nose, so looks like I am gettting there at last. I will still check the spindle for truth, once it has been removed from the headstock.

Any tips on removing the spindle from headstock ? I take it that there are two allen keys to rmove and the endfloat adjuster and pinion and to catch the thrust bearing balls in a box !!

Thanks for all advice so far.
MIke.

[Brian WoodParticipant @brianwood45127]

Hello Mike,

The very fact that you have improved the apparent run out error with your reamer gives much more support to the cause coming from some 2 MT socket trouble. There must be a small bruise in it somewhere.

It is a rather long time ago now since I removed the spindle on my father's old lathe and that was to change the belt as far as I remember. I don't recall allen keys but you may have to draw off the 25 T pinion, it is a very snug fit on the plain turned diameter on the end of the spindle. Watch out for the copper shim under the grip screw for the end float ring. I think that the balls are captive in the thrust bearing but be prepared. It all has to come out over the lathe bed of course.

Refitting the 25 T gear and then matching the two halves of the 2BA locking screw can take time.

Regards Brian

[sparky mikeParticipant @sparkymike]

Thanks Brian, all good info. What might simplify the gear refitting, so that the 2BA screw would locate easier might be to insert a rod into the screw hole to act as a guide. The rod would need to be fraction under the root size of the 2BA screw. (I always look for an easy way out !!)

Might not work ,but worth a try, especially if the gear is a very tight fit.

Mike.

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