Screwcutting Clutch for Myford Lathes

[Michael GilliganParticipant @michaelgilligan61133]

I was interested to discover that Martin Cleeve's Swing Clear Tool Holder was also published in Popular Mechanics.

MichaelG.

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Edits: Corrected typos

Edited By Michael Gilligan on 27/02/2015 08:53:07

Edited By Michael Gilligan on 27/02/2015 08:54:53

[Chris TriceParticipant @christrice43267]

So because one guy did it to your personal lathe, which obviously irritated you, all owners of Myfords have to be tarred with the same brush John? Your previous machinery ownership is completely irrelevant. It read as a smug swipe at all Myford owners. Sorry, but it did.

[John Stevenson 1Participant @johnstevenson1]

OK have the last word.

I was married long enough to understand that argument

[Bob McParticipant @bobmc91481]

Hi All… Michael Gilligan wrote on 25/02/15… "Replace outboard gearbox with 'electrickery' & stepper motors"..

Here is one I did earlier using 'electrickery' .

Bob.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Bob Mc on 15/03/2015 13:42:30:

Here is one I did earlier using 'electrickery' .

.

Welcome, Bob

That looks very tidy

… More details please !

MichaelG.

[Bob McParticipant @bobmc91481]

Hello Michael and All… Michael asks…"More details please!".

Its a bit of a story really,

I was given an old Atlas 10F lathe, the tailstock was missing, the leadscrew was worn out and there was no backgearing; it was to go for scrap, I thought it a shame since the bed ways were ok and so I used a piece of 20mm diameter stainless threaded rod for the leadscrew.

After successfully making a new clasp nut the lathe seemed to be performing rather well and gave me the impetus to have a go at making a slow motion drive for the leadscrew; at this point I must tell you I worked in the electronics industry for many years, and although it was easy enough to fit a motor to the leadscrew I had by then seen the Electronic Leadscrew Groups website and was considering making one of their designs, however the cost was rather excessive and I only wanted something which would do the screwcutting..whereas their design was bordering on full cnc.

So I designed my own using Arduino microprocessor boards, the leadscrew control can cut any thread with a reasonable degree of accuracy and will even take into consideration the inaccuracy of the threaded rod 'leadscrew'… The control box can also be used to provide slow motion of the saddle and of course can be sped up to go along faster or slower manualy.

It has taken some time to get things sorted out and I have to admit that headstock drive stepper motor is rather underpowered, however using fine cuts I have made a number of internal and external screw threads, one of which is used on the lathe itself.

It might not be pretty…but it works.

Let me know if you want any more info.. rgds….Bob.

[Michael GilliganParticipant @michaelgilligan61133]

Bob,

Thanks for the additional info.

Personally: I would be very interested to see this written-up in MEW, and I know there are others interested in using Arduino.

MichaelG.

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Open request to Neil: … Please get this man writing !!

[OuBallieParticipant @ouballie]

Bob,

Now that ticks all the boxes for ingenuity.

Lots of questions, but don't want to pre-empt publicTion of any future article.

Wish I knew more about electronics, but those Arduino boards looks interesting.

Neil,

Make Bob an offer he can't refuse!

Geoff – Still trying to get my head around video production and faIling

[Neil WyattModerator @neilwyatt]

If you want to get in touch about an article, Bob, my email is neil.wyatt@mytimemedia.com

Neil

Edited By Neil Wyatt on 17/03/2015 17:35:54

[Bob McParticipant @bobmc91481]

Thanks Geoff, … kind words come from a kind person.

I am hoping to do an article about the 'electrickery' device… have emailed Neil… will have to wait & see, so I can't really say too much about it at the moment.

rgds …Bob.

[thaiguzziParticipant @thaiguzzi]

Posted by Chris Trice on 28/02/2015 11:41:30:

So because one guy did it to your personal lathe, which obviously irritated you, all owners of Myfords have to be tarred with the same brush John? Your previous machinery ownership is completely irrelevant. It read as a smug swipe at all Myford owners. Sorry, but it did.

Alright, i'll be smug. Why can you buy 3 (three) good AUD Boxfords (that's powerfeed, g/box etc) for less than the price of a Myford S7 with QCGB? Probably 5 Raglans or little Johns. All superior, heavier duty lathes with a similar footprint. Snobbery? Pot calling the kettle black?

[Jon GibbsParticipant @jongibbs59756]

[…..any chance of getting this thread back on course?]

I really like the look of the Martin Cleeve's 15:1 reduction gearbox idea for my old ML7. I've read Martin's book and am convinced by the arguments against automatic gearboxes but without his gearbox it does make switching back to fine feeds a real pain.

Even though I admire the patience and skill of the full electrikery solution I can't help feeling it's a lot of work and a bit like plumbing a Japanese toilet into a privvy

What about a sewing machine motor and foot controller with a 20 tooth drive gear on the output in place of Martin's gearbox?

Does anyone know how slow these motors will go? **LINK**

Sad to say that for the price of the motor and foot control (£35) I'd be struggling to have bought the set of gears required for Martin's solution.

Jon

[EmgeeParticipant @emgee]

Hi Jon

IMO you can forget about a sewing machine motor for your application, not sufficient torque at any speed.

Emgee

[Jon GibbsParticipant @jongibbs59756]

Hi Emgee, Thanks for the reply – Back to the drawing board then.

Perhaps I should persevere with Martin's gear box idea.

I've been looking through the C2 lathe spares on the ArcEuro site and I think that a plastic geared version using C2 change gears and a re-purposed timing belt may be the way to go.

I have a spare 20 tooth Myford gear for the output drive to the dropped banjo.

Any thoughts on the strength of the plastic gears in this application? If I need metal gears where should they go, input train or output?

Jon

[Michael GilliganParticipant @michaelgilligan61133]

Jon,

I think it should be possible to make a very serviceable speed reducer using two sets of 4:1 ratio toothed-belt [timing] pulleys arranged like a backgear. … Overall ratio 16:1 and it would be very compact.

Given that Martin Cleeve's original gearbox was driven by a 'spring' belt drive, I reckon that XL or similar belts, on plastic timing pulleys would be quite adequate.

MichaelG.

[Neil WyattModerator @neilwyatt]

Hello Bob – I don't seem to have received your email yet…

Neil

[Jon GibbsParticipant @jongibbs59756]

Michael,

Thanks for the tip, I'll look into it.

Jon

[Bob McParticipant @bobmc91481]

Hi Neil…

I have re-posted but there is a problem with sending to the address you gave me, anyway, the answer is basically

Yes.. will try emailing again.

[Neil WyattModerator @neilwyatt]

Sorry Bob, I left one 'me' out of mytimemedia

Can you try a third time for me, please.

Neil

[QParticipant @q14709]

Bob, yes please publish your design for the electrickery device, I'm working on ideas for just such an item for my ML7 and have discarded the electonic gearbox groups approach for the same reason as yourself. Please do tell all, my Arduinos await with anticipation

[Bob McParticipant @bobmc91481]

Hi Q….

I am in the process of writing up an article for Neil, so I can't really say much about how to construct the thing when it may become an article, and at this moment in time I still await Neil's confirmation of how long an article he would like but as yet I have not had a reply, having not done anything like this previously I do need an indication of what to do next.

I can tell you that it actually has similarities to the Myford Screwcutting clutch albeit in electronic form so it does have some bearing on the topic of this forum.

I don't think I will be saying things out of place if I say that it would be best to have a reasonable understanding of the Arduino, I only ever had Simon Monks "Programming Arduino" which is more than adequate for this project; read up on the use of the Interrrupt function, I can honestly say that the programs are so simple you don't need to be an expert.

Bob.

[Bob McParticipant @bobmc91481]

Re: Hi Q…

I do apologise to Neil, he has actually sent me a message on the 17th, I am new to these forums, did not realise I had an 'inbox'.

Bob.

[RobboParticipant @robbo]

Bob,

at the top of your inbox you will find a box marked "send me an email alert when a message arrives"

Tick this and you needn't remember to look every time you log on.

[QParticipant @q14709]

Hi Bob, I await your article with great anticipation. Ihave already built several Arduino based projects including a bell and horn emulator for my clubs new petrol/electric American Switcher Style locomotive, Yuriey's DRO project and a few others. I was going to design the screwcutting electronic gearbox from scratch but it's always nice to be able to follows someone elses design as so much of the hardwork has already been done .

Good luck with the article and many thanks.

[alan smith 6Participant @alansmith6]

I missed the start of the thread and am posting these comments regarding our hero Martin Cleve. Some of you may remember the thread "Stringer EW lathe" in which I reviewed the articles written by Martin for improving the EW lathe. The fact is, that in my opinion, the designs he made for the Myford improvements did not scale down suitably when he applied them to the EW.

The worst case is the "Grandfather clock" movement for the slow speed, which is probably one of the worst designs that I`ve ever seen. The same goes for the larger unit for the myford placed inline withe the rear of the spindle. Health and safety would certainly have had a few issues with this design.

Martin was a frequent contributor to the ME and earned a lot of money doing so but some of his designs have to be taken with a pinch of salt and some are unnecessary.

It`s the same today, we all love to read those articles in those beautifully produced magazines but does anybody ever make the designs portrayed within their pages?

Lastly, the Myford as a design cannot touch the superior design of the Boxford which was copied from the American Southbend lathe and it was a "precision lathe which Myford never made any claims to be!

Alan

Edited By alan smith 6 on 17/07/2015 16:34:53

Edited By Neil Wyatt on 17/07/2015 17:20:45

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