I would have thought you just need to make a new ring and engrave it with half the number of divisions.

EDIT. I'm not really a Myford man but it has a 10tpi screw and the handwheel is usually divided into 100 divisions eg 0.001" each which would be direct reading  of cut not diameter

Edited By JasonB on 11/12/2014 20:12:03

As he wants to be able to read "the amount of cut" I was thinking 50 divisions rather than 100 so each turn division would be a one thou advance of the tool.

But my edit suggests that is what the Myford already has a direct reading of depth of cut not reduction of dia.

Can any ML7 users confiorm the tpi and divisions on teh wheel as to me it looks like a direct reading of cut anyway??

Jason,

This [cross slide] one is bent and worn, but it's standard Myford

10 tpi and 100 divisions  =  Direct reading of displacement.

MichaelG.

Edited By Michael Gilligan on 12/12/2014 08:01:07

"direct read the amount of cut"

But maybe Martin wants to read "amount cut of the diameter" where most of us would term "cut" as the depth of cut eg how much the tool advances

If it is a reading of diameter reduction then yes 100 divs of 0.002" each would do it and is what is on my lathe.

J

PS thanks for the confirmation Michael

Hi Martin, what you have is the industry standard, all the machines I have worked on over the last fifty + years have this format, Smart & Brown, Colchester, Boxford, DSG, and my own machines Myford and Emco and few others I can't remember . That's not to say that there may be exceptions but I have never seen any.

To do what you want you would have to half the division or make twice as many divisions on your dial — same result ! This would mean that one division would move the tool 0.0005" thus take a cut of 0.001" off the diameter of the work.

Hope this makes it clear to you but if you persevere you will learn to accommodate the standard format and remember if you do choose to alter your machine any other you may start using will give you the same problem. My advice would be stick with it !

Regards John

Edited By JohnF on 12/12/2014 09:27:09

Never used a Harrison then! On my Harrison M300 if I move the cross slide by 10 thou on the dial then the work is reduced by 10 thou on the diameter. Seems more logical to me, as what you're really interested in is the size of the work, not how far the tool moves.

Andrew

Unless you're screwcutting?? I don't see a problem, multiplying or dividing by two in my head doesn't exactly stretch the grey cells.

Russell.

Or keep your division ring and make a 20 TPI leadscrew

I remember reading somewhere that on Imperial lathes the cross slide dial graduations show the depth of cut and on Metric machines, the dials show the reduction in diameter.

I've got two lathes – one Imperial and one Metric, and I get confused when working between them, but I put that down to me old age!

Dave
The Emerald Isle

I assumed that dial readings on any machine tool was the actual movement of the slide, until I got an eastern lathe. This has all showing the actual movement except the cross-slide which shows diameter reduction. Took a while to realise that, I don't like the idea but am now used to it. Bores are a real brain ache, thread cutting just needs a bit of thought. When I get the time I do intend to make a new dial, but by then it will be second nature.

The Colchesters I have used (Bantam, Student and Triumph) all take off the diameter, I have just looked at a DSG type 15 and Herbert capstan, and the cross slide on both take off the radius. It looks you have to get used to what you have got as there is no standard.

Mike

Both arrangements have their niche: Therefore, neither can be 'correct'.

Maybe we need a nice little MEW project to make quickly interchangeable dials; so that you can use the appropriate dial for the job.

MichaelG.