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Peter N
04-23-2009, 04:28 AM
This is probably of more interest to the UK guys, but the link below tells the story of my Myford ML7 rebuild.

http://www.onepoint6.co.uk/Myford/index.html

There was an ulterior motive in posting the rebuild story, in that the ML7 is now up for sale.
However, there are lots of pictures and I know you guys like that, so perhaps a bit of something for everyone.

Peter

Alguy
04-23-2009, 05:19 AM
Nicely done Peter, I read it and was very impressed. :D

The Artful Bodger
04-23-2009, 06:08 AM
Nice job Peter and good luck with the sale.

Forrest Addy
04-23-2009, 07:20 AM
Peter So many of the "rebuilds" I've seen proudly presented on various websites amount to nothing more than a clean-up, paint job, and minor repairs so it was a pleasant surprise to open your link. Yours is as comprehensive a narrative on the level of detail and logical work order as any I have seen treating the reconditioing of an engine lathe. I would like your permission to copy it with all photos and illustrations so I can offer it as supplemental materials for the scraping classes I teach. It will demonstrate fpr machine tool scraping neophytes the scraping processes and the steps in rebuilding - even a simple lathe like a Myford for which an active replacement parts organization still exists.

I congratulate you on your mastery of the rebuilding processs and your clear headed and well ordered presentation. It truely belongs in a text.

I wish you had had space to present the many tests and checks, the equipment you used, and your method of checking for fit and alignment. and then final accuracy tests. For example there is little discussion on lowering the QC box, lead screw and bed rack to compensate for the reduction in way bearing material; also relocating lead screw and nut axes for the cross slide and compound axes.

However yours is a sales pitch not a how-to so I guess we can't have it all. For the record, had I a need for a small lathe and the price and didn't have a 5000 mile shipping route I would snap that machine up. If all the work on that machine uwas as competently done as the work shown it might be a superior machine to that the factory makes.

Forrest Addy

Circlip
04-23-2009, 07:34 AM
Let Norm's best mate know where you're posting it Peter :D

Regards Ian.

John Stevenson
04-23-2009, 01:41 PM
Let Norm's best mate know where you're posting it Peter :D

Regards Ian.

Who's that ? Lewis ?

.

Mark McGrath
04-23-2009, 05:33 PM
Who's that ? Lewis ?

.

Ok,I`ll walk into it.Who`s Lewis?

Mark.

John Stevenson
04-23-2009, 05:48 PM
Judging by Norm's classical education I thought he resembled a poor man's Inspector Morse.

I can't understand him at times ............

Norman Atkinson
04-23-2009, 06:13 PM
But a Lewis is an ancient pulley system.
Sounds vaguely like your last article on pulley wheels on-------Myfords.


Oops

Norm

Alistair Hosie
04-23-2009, 06:24 PM
you did a great Job all round but then that's a great little machine .wow myford's know how to charge for parts don't they? keep well Alistair

Norman Atkinson
04-23-2009, 06:50 PM
But John- I haven't got a Classical education.

When you passed over the Tyne today on the way to Morpeth, there were the factories and the rows and rows of colliery and factory houses.
I left school in 1944 at the age of 14 with no education to speak of.
Those houses were part of where I am proud enough to claim as mine.

No university!

Norm

Mark McGrath
04-24-2009, 04:29 AM
Ok,I`ll walk into it.Who`s Lewis?

Mark.

Wasn`t thinking when I wrote that.Thanks to Norman for reminding me.

Mark.

Norman Atkinson
04-24-2009, 05:44 AM
The plot within the plot?

Endeavour( oh, yes) Morse had no offspring but he adopted his sergeant as his successor.

In freemasonry, the son of a mason who comes into the lodge is 'his Lewis'

It's repeated in all sorts of things.
Lord Trenchard who was father of the Royal Air Force was a mason, police chief and who knows what, was a very senior and formed the RAF Apprentices scheme. His 'Lewis's' were and are known as 'Brats'

Not quite the classicist, John, eh?

Now do you really want to talk about motor bikes? There is the Harry Atkinson trophy somewhere. Harry had a brother, my father. I moved on.
Harry had a father- days of first steam. Sam had a father back in Shildon.

Both moved on.

Life is like that. It's called 'Endeavour'

Cheers

N

Norm

Peter N
04-24-2009, 08:54 AM
Thanks Guys, I had a lot of fun doing the work as well as using the lathe.

Forrest, thanks for that. Please feel free to copy and use whatever you want.
I've gone through it again this morning to (hopefully) correct all the typos and spelling errors.

Rebuilding it and checking it to make it was right was a learning exercise all by itself.
I don't have large straight-edges or angle straight edges to check dovetails, so many areas had to be referenced off other parts that were known to be good.

For example, under the headstock casting are 2 square-machined 'blocks' at the front and rear that were designed to locate between the shears and against the inside back shear face for alignment.
On the front bed (headstock end) shear face are 2 tapped holes for 'pusher' bolts to align the headstock with the bed.
The headstock casting had obviously moved a little bit over the past 38 years, so despite the re-grind and newly machined shears the blocks on the casting couldn't be relied upon to be exactly co-linear.

I had to make up a small surface ground angle plate to carry a clock, that slid along the top on the rear bed surface and referenced off the machined shear on the side to clock along the length of an MT2 test bar in the spindle to check alignment. A fair bit of adjustment on the pusher bolts, some shimming, and a little scraping was required to get the alignment right.
The best part of a day to make the 'L' block, and another entire day to set-up, measure, adjust, re-measure, adjust (and so on...) are just one of the things that aren't shown.

Once the headstock was square and clamped, then the MT2 test bar in this could then be used as a reference for the saddle and the talistock.
It's a big learning exercise and sometimes I'd get a reading that just completely puzzled me as I couldn't figure out where the error was for ages.

Peter