ML7 tailstock barrel thread and so on....

I am contemplating a modification to the tailstock of my ML7. Having formed the opinion that the thread size on the tailstock barrel is - Acme, Right Hand, 1"-8. I am now on a hunt for a matching nut.

I have located nuts on McMaster-Carr website with the above attributes (but it is far away and expensive to get it here - for one nut.)

My questions.

1. Have I got the thread characteristics correct? (a.k.a have I missed something)

2. Can anyone advise of a supplier on this side of the planet.

From my limited probing eBay is out and China does not seem to have them either.

Thanks in advance for whatever consideration you can give my request.

Regards

Frank C.

Pretty sure it is a left hand thread from my notes when I made my ML7 lever tailstock attachment. LINK

Easy enough to screwcut with a shopmade HSS toolbit in a standard boring bar.

If it is a lever tailstock you are making, the full drawings and pics are in the latest two issues of MEW, 323 and 324. In the final design I did away with that thread and just used a plain-bored clamp as Myford did in later years.

Edited By Hopper on 15/02/2023 00:05:30

Hopper

Unbelievably helpful. That pretty much answers everything I could have thought of asking and probably changes the direction of what I was attempting.

I was not originally thinking of a lever arm, more of an extension cover as on the Super 7 thereby moving the hand wheel so that the threaded portion does not protrude through it. However your lever arm is a more desirable approach, I was hoping for a reasonably priced item to appear online but you know how that is.

Never having cut a thread (on the lathe) I'm .... uncertain .... but an opportunity to learn perhaps.

In any case that is a great build and lots of information to pour over.

Also can't believe I missed that build first time round (and the damned thread is left hand!!!!)

Thanks again.

Frank C.

Edited By Chuck Taper on 15/02/2023 08:40:37

Glad you might find it useful. I am sure you can get away without cutting that Acme thread, as Myford did in later years and just use a plain hole relying on the clamping force of the pinch bolt. Or leave a little step at the far end of the hole so the tailstock barrel can't pass all the way through. It has the added advantage of being quicker to take on and off too. Although, once fitted, mine has stayed in place. Yet to find a situation where I want the old handwheel back.

Yes the original Myford lever attachments seem to bring high prices these days, hence the shopmade approach! Cost absolutely $0.00 out of the scrap box. That's my kind of project!