The ML4 is a relatively small lathe, so you would have been better to have gone for 8mm tools. NOW he tells me!

is there any chance that you could return the tools in exchange for 8mm?

If not, you need to remove 2 mm from the shank of each tool, by some reasonably accurate means.

In normal times someone in your local M E club would probably have been able to do this for you, but now it is more difficult, but probably not impossible.

Whereaboiuts are you? It may be that someone on here would be prepared to have a go at the job for you.

With response to your query about the handle for traversing the Saddle, yes you need a locknut. Having adjusted the end float to the minimum, consistent with ease of movement, the locknut then locks the handle to shaft in that position. Needless to say it will be BSF or BSW, so you may end up making your own!

If you read the Myford ML1 – 4 pages on Lathes UK, you will learn a great deal about the machine, and it's quirks.

If you can find the Serial Number, Jon Cameron may be able to give some idea of the year of manufacture. (PM him )

I have helped recommission a ML4, but not one with damage such as yours. (Your previous owner looks to have engaged backgear as a means of unscrewing a stuck chuck. You now now know why this not advisable.

That machine did not have Tumbler Reverse, and although it had a complete set of Changewheels, no studs on which to mount them!

The owner was not interested in cutting screw threads, but I cut an extra 20T gear and modified a 60T from a ML7 so that a fine feed could be set up, using the studs that I made. This allowed a fine feed of about 0.004"/rev to obtained.

I would suggest making a Centre Height Gauge, to help you set tools to centre height, to ensure that they cut properly and well.

Since the threads used on the Mandrel changed over the years, it might be worth making up an adaptor from whatever your machine has, to the "standard" 1.25 x 12 tpi. This will allow you to mount the post 1947 Myford thread chucks or their backplates.

I am not an expert on ML4s, (There are others more experienced than I, on here ) by any stretch of the imagination, but if I can help in any way, PM me.

Howard

There should be a locknut of some kind to hold the small gear on the shaft, but you can probably get away with a thread locking fluid, at least temporarily.

If you have the original tool clamp, it should be possible to machine the base of your square toolpost to get it down to centre height for the 10mm tools. Best done in a 4 jaw chuck, but can be managed in a 3 jaw. Quite a good project to learn on.

I doubt if a mini lathe toolpost will fit without a modification of some sort, so it is worth seeing what you can do with what you already have.

Hi Andrew,

I wont go into detail with removing bull gear as already said above if you search out the thread Brian covers that very well, but if you get stuck my machine is currently apart so I can provide pics of assembly if required.

The gear on the apron, it does screw on, behind it is a small 1/4" split washer, before it goes into the apron, if yours keeps unscrewing then firstly turn it around so that the unused section of the gear is facing the lathe bed when installed this will help to lower some backlash on the traverse. Remove the gear and clean down/degrease. put a little threadlock on the thread (just a drop) before screwing the gear home flush with the end of the spindle. On the other end of the apron there should be a washer and a locknut to adjust the tension a then the handle screws on up against the handle to secure the assembly.

I haven't had experience of the quick change toolposts, I use a four way toolpost that came with the lathe, it takes a variety of tools from 1/4" upto 3/8" and all are on centre, when used in conjuction with packing strips or steel, and beer can for fine adjustment, you'll have to finish off the contents first but i'm sure that wont be much hardship.

As Howard says above, Im compiling a list of serial numbers for the lathes, and id be interested if you could provide yours, though looking at just the headstock I am assuming it to be a later one.

Regards

Jon

Edited By Jon Cameron on 11/05/2020 11:07:08

Hi Andrew,

The thread on the change gear side to take up end float on the spindle, is that correct????

32tpi rings a bell, its published on the internet somewhere, let me have a look, failing that I can measure it with my thread gauge for you tonight.

Jon

Edit yes it is 32TPI, I would not however run a die down it as the lock nut and spindle thread need to be quite a close fit. So as Howard suggests take a file or even some fine emery paper (1000grit) backed onto a file to clean up any burs. I will be fitting a brass plug under my screw once its back together to prevent the issue you have, (mine is tight but it will still go but I don't want it any worse.

Edited By Jon Cameron on 28/05/2020 10:01:49

Hello Andrew,

When you come to fit your new chuck, and just out of interest, try applying David Bennett's recently reported findings on the actual value of the horizontal register.

As long as the vertical register is true and the nose thread reasonably sound, he and others have found that this combination works perfectly satisfactorily.

If it 'offends' you to ignore the horizontal register, at least the new chuck will hold things satisfactorily for you to make a collar as I described earlier. When I did the modification, I recall using a piece of old water pipe as stock material rather than making it from solid

Kind regards Brian

Hi Andrew, Do you have a faceplate that will locate onto the current spindle?

A slightly oversized piece of roundstock could be clamped onto the faceplate then drilled and bored, then threadcut to take the thread on your spindle nose, then file two flats to lock and unlock it from the spindle as Howard suggests above. You may need an angle plate bolting to the faceplate to provide sufficient holding onto the piece of stock. this will form a sort of keats (or Keets??) angle plate. Once the internal thread is done, thread it on the machines spindle and do the outside with it in place.

There's a lot to think about but the outside thread needs to be done with the adaptor fitted to the spindle to ensure accuracy. the internal thread and register, is what will give location to the adaptor, doing one side mounting then turning the outer will help to ensure alignment to the lathes spindle. if you have the faceplate an angle plate can be bought for £20-30. and will prove useful again and again. a piece of flat bar (no less than 4mm, but thicker better) with two holes drilled for clamping bolts will suffice if you don't have a full clamp set.

Hope this helps

Jon

Brian there are three nose threads that I have come across on these lathe, 1.1/8" 12TPI as standard on later ML7 ect, also two 7/8" threads, one 9TPi, and one 12TPi, My ML4 has a 9TPI one. but your correct I cant see reference to it either perhaps it was mentioned on another post…..? If Andrew could clarify that would be great.

Jon