Drummond M hand wheel problems.

[zx9]

As per my post in what have you made today, I have been cleaning up the tail stock of my Drummond but have run into a slight problem with the hand wheel, well two problems actually:

The first is relatively easy, the split CI retainer ring has worn the grove in the cast steel some 1.8mm wider, you can just see the shoulder in the grove. Do I weld some the edge of the grove with Mig which will be quick or do I build it up with Tig which will be good practice but much slower? Does TIG machine any easier than Mig and would either be kinder on the CI retainer ring when I re fit.

The next problem will be more difficult for me.

Part of the internal square cut thread is missing on the first two threads, it may have broken at some time but it looks almost like a casting defect, surely Myford can not have been this sloppy building the last few post war Drummonds.
The questions are:
1. Ignore and re assemble?
2. Fill and re cut the thread, same question as above, Mig or Tig weld? Then clean up with a boring bar and try to grind a suitable internal square thread cutting tool and pick up on the old thread? I am happy with internal threading using a 55 or 60 deg insert but this look a lot more difficult.
3. Go on the bay of Es and try to buy a better one? They do come up quite often but will all be over sixty years old so could be just as bad as this one.

 

[Hood]

First one I would just turn the groove to a square edge and either make a wider clamp or put a spacer in.
Second I would ignore.
The other option would be to make a new handle up yourself.

 

[zx9]

First one I would just turn the groove to a square edge and either make a wider clamp or put a spacer in.
Second I would ignore.
The other option would be to make a new handle up yourself.

I am liking your opinion on the internal thread.
The first would be more doable if the retainer was not a split CI ring, machining another thicker CI ring would be an option but adding a sub 2mm split spacer would be tricky which is why I was thinking of building up the existing one with weld.

 

[Ian James]

I agree with Hood on this one it's only the first two threads and there is plenty left

 

[Hood]

Not sure how the retainer fits or what the retainer even looks like as it must be over 20years since I had the M Type.
Would it not however be possible to make up a spacer and glue it to the side?
Does the retainer have to be cast? Would making a completely new one from something like Delrin not be an option?

 

[Ian James]

Well I have just pulled mine off and guess what the first 2 threads are fubar

 

[Hood]

I imagine that will be very common as I think that will be down to people trying to extend the tailstock too far and thus putting pressure on the last couple of threads.

 

[Ian James]

Pics that should of gone with the above post

 

[zx9]

Pics that should of gone with the above post

Thank you for the pics @Ian James , I was just about to go outside and take identical ones. Looking at yours it does look like either they all get damaged or it is a casting error so I will not worry too much about the threads. Oddly my retainer ring (s) have hardly any ridge, yours are much more worn it is the steel hand wheel that took the ware on mine giving a couple of mm free movement on the quill.

 

[Pete.]

I would part off a 2mm steel shim, split it and araldite it to the cast iron ones then drill the holes. Then I would cut the groove for a nice fit and assemble it. The broken threads I would ignore.

 

[zx9]

I had the afternoon to play with so I thought, lets build up the worn part with weld, reasoning that if it all went wrong I could a, turn off the weld and be back to making a spacer or worst case buy or make a new hand wheel. So in the best of internet tradition I asked a question received good advise and preceded to ignore it, sorry @Pete.
Not a lot of Argon for the tig so out with the mig, weld was a bit high but looked ok and I had not destroyed the internal thread, all good so far.
Clocked up in the four jaw and away we go, a bit noisy with the interrupted cut but all was good until I got down to the parent metal which turned out to be CI and some of my weld was not exactly fused to the hand wheel. Ho hum.
Still most of the weld was still there so I went ahead with the parting tool and gut the groove to match the CI retainers.

The good news is it works all the free play is gone and the scabby bit is hidden by the body of the head stock and retainers.

If things go Pete Tong I will turn out the remaining weld and make spacers.