Thread: Info on Mc Millan lathe

Hi guys,
trying to sort out some problems with a friend's McMillan Ml-36 lathe which has a regular tight spot on the longtitudinal traverse and a non continuous rotation of its feed shaft - I see that the traverse handle shaft and spur gear to rack are on different planes so may need to remove apron to check for damage but am loath to proceed until I receive workshop manual from Tony Griffiths in the U.K - If I turn the feed shaft by hand there is a point where one feels a 'detent' position?? When feed is engaged it works for a while then stops, Does anyone have a manual here in Oz which I can copy?Any advice would be appreciated.
Regards - stay safe
Alf Scotting

Hi Alf, I found I had posted some stuff about the McMillan Lathe in the past which was here https://metalworkforums.com/f65/t199...millan-ml-36-a I don't know if the Lantaine lathe manual is the same or not, but it might help http://machine.archives.verhey.org/f...fe8d87dae6.pdf and that link is on the page for the link above. I'm not sure what the problem with the feed is, but I would be checking the pins both through the feed shaft and through the carriage handwheel spur gear. It could be that the pins which are supposed to shear in the event of a jam up might be broken, but still catching enough to drive a bit.

I have one of these lathes.
Your feed shaft problem is probably a sheared shear pin.
In the pic below. There are two sleeves on the feed shaft and leadscrew. You undo the grub screw and slide the sleeve towards the tail stock end. (When I was pulling mine apart both sleeves were quite tight and took a bit of effort to move them) Once the sleeves are moved you can see the holes with the shear pins. One of mine had been replaced with a roll pin (sellock, spring pin etc)
Its a while since I did this so I'm not 100% sure but I think I used a brass pin which I grooved a bit either side at the shaft dia. (hope that makes sense) As far as shear pin strength, it was a total guess on my part. I figured if it wasn't strong enough, then Id make the next one a bit stronger. Id rather have the pin shear than bust something in the machine. 18 months or so later its still going ok.
Somewhere I have a scanned copy of the manual that came with my machine when it was new. Its actually for a Lontaine and its not exactly the same as my lathe. My late father bought the machine from a bloke who had bought it new and that was the manual he got with it.
Hope this helps.
Peter

Originally Posted by bollie7

I have one of these lathes.
Your feed shaft problem is probably a sheared shear pin.
In the pic below. There are two sleeves on the feed shaft and leadscrew. You undo the grub screw and slide the sleeve towards the tail stock end. (When I was pulling mine apart both sleeves were quite tight and took a bit of effort to move them) Once the sleeves are moved you can see the holes with the shear pins. One of mine had been replaced with a roll pin (sellock, spring pin etc)
Its a while since I did this so I'm not 100% sure but I think I used a brass pin which I grooved a bit either side at the shaft dia. (hope that makes sense) As far as shear pin strength, it was a total guess on my part. I figured if it wasn't strong enough, then Id make the next one a bit stronger. Id rather have the pin shear than bust something in the machine. 18 months or so later its still going ok.
Somewhere I have a scanned copy of the manual that came with my machine when it was new. Its actually for a Lontaine and its not exactly the same as my lathe. My late father bought the machine from a bloke who had bought it new and that was the manual he got with it.
Hope this helps.
Peter

Thanks guys, all sorted, spur gear driving rack is bent and I will check shear pin - Manual arrived from Tony Griffith which is excellent