Rare Myford Lathe rebuilds.

[ed731pdh]

Col.

I agree with you concerning transwave convertors, but getting a three phase connection installed is not a cheap option either if you are working out of a garage. Me and three phase have an uneasy relationship at the best of times, but other than a convertor I can see no point.

Smashing job on the re-grind, can eat your dinner off of the bed (DON'T), that work should see you out. This is just the sort of heavy engineering that has dissapeared or has been exported to the far east that we really desperately need.

Paul.

[Retired]

Hi,

Flat belt drives are problem these days Rob and I can understand your problem in needing a correct motor drive pulley; these are still available but need a bit of tracking down. Many years ago I bought a big circular saw that was driven by flat pulleys and I converted it to V belt drive. when I go into the garage I'll have a look to see if I still retain the old pulley. As I mentioned in my email; you could take your time and fully restore this excellent lathe and convert it to V drive. Once the lathe is restored it will outlast the modern variable speed lathes fitted with lots of electronics to go wrong. I like these type of lathe for their simplicity and robustness. I'm also aware of your change gear problem Rob but the lathe will produce first class work without a single change gear; it won't screw cut or have power traverse of course but I've managed without now for a number of years working on my vintage MF36. I've only ever used the leadscrew to cut threads during my apprenticeship almost 50 years ago. I get by using taps and dies. I do miss the power feed though that I had with the Colchester but it doesn't prevent me from producing top class work on the MF.

I don't know what workshop facilities you have at your disposal Rob but three step V pulleys are widely available which would help if you decide to convert the drive system. Removing the headstock mandrel is actually very straightforward on these lathes all you need to do is to make a sketch and take notes of the components as you remove them. In particular the thrust bearing and spacers. On mine the ball bearings are retained in the race so removal doesn't mean ball bearings hiding in the black hole under the bench. I think once you start the restoration you will be surprised how simple it actually is. Take plenty of time and enjoy doing it. You will then have a friend for life which will hold its value.

With hindsight I fully agree with your comments Fido and thanks for adding them. Buying unseen is always a gamble but in the end it will come right for me and had the lathe been in good condition I would have missed out on the fun of restoring it. By doing it this way the bed is returned to as new accuracy and I think it may well turn out to be a lathe to keep. With 36" between centres it actually takes up little space sitting on the bench; the motor at the moment is mounted on the garage wall so doesn't use space beneath allowing plenty of storage. The day I collected the lathe was a bit stressful. I had to hire a van so hired a Transit because I wasn't sure if the bed length would fit into a small van.

I think in total the van hire with insurance and fuel amounted to some £70 for a day's hire. I collected the van in the morning and was just settling into driving it when I ran into grid lock on the M62 west bound; I sat in the jam for well over an hour.By the time I arrived at the sellers home in North Wales it was after midday. I wanted to return the van before the hire company closed at around 5.30pm. In order to load the lathe I had to strip it down to enable two of us to lift it.. I didn't have the time to start inspecting the lathe and to be honest as I looked around the workshop I thought the description as to it's condition would be fair.

This must be the fastest travelled lathe ever on the return journey. I had to unload it on my own into the garage and at last I could return the van just in time to the hire company. It turned out to be a hard day and as I stated previously I was quite a while before I got around to re-assembling and inspecting the lathe by which time I had left positive feed back on eBay. I never go back on a deal even if I feel entitled to do so; I bought the lathe unseen. I won't buy another lathe unseen though.

Thanks Paul; Transwave static phase converters work in a fashion but don't give full 3 phase power and I found it a pest having to keep adjusting the output control for each machine I was running; at the time I had three 3 phase machines hooked up to it. My big Colchester and huge Dominion woodturning lathes and also the double ended pedestal grinder. I was happy to let the converter go with the Colchester.

Like you Paul I used to think installing 3 phase 415V into my workshop or garage would be hugely expensive. The fact is that I installed 3 phase 415V giving up to an estimated 10HP output for just under £120 and I'm not joking either. Many of my friends have seen it in action and the beauty about it is that once each 3 phase machine is phase balanced to the transformer they not only work on full power; they can be switched on and off just as though regular 3 phase is installed; I demonstrate this by switching on the big 3 phase bandsaw and whilst this is running also switch on the 3 phase dust extractor. I used to hate using the Transwave to power up the dust extractor as it used to take forever to come up to speed; with my transformer it comes up to speed almost immediately. I know of a guy in Wales who needed 3 phase installing into two large farmhouses to power heat exchangers; he was quoted by the local power company in excess of £17,000. I was one of the first in the UK to install this 3 phase system and it is brilliant. I'm a mechanical engineer so playing around with this amount of electricity was a major challenge; I'm not skilled in electrical work but hopefully I know what not to touch. I've posted the link before but here it is again;

http://unique3phase.com/

I was brought up with huge machinery and find it heartbreaking to see all our heavy machines go abroad to be replaced by fast food outlets locally.

I've just returned from buying paint for the restoration; Bron selected the dark green colour as I'm colour blind. I bought 2 litres of Synthetic Enamel which I'm assured once it cures will be up to the job; I also bought 1 litre of correct thinners plus a roll of masking tape. Not cheap these days at £43.98 for the three items but bless the government for boosting the cost due to £7.33 VAT being added. 20% VAT is sure to encourage others like me to spend on materials to create jobs.

I've never sprayed enamel before and I'm told it will take a few days to fully harden unlike the auto lacquers I usually spray which flash off very quickly indeed. I hope I don't get any runs or curtain whilst spraying.

Kind regards, Col.

[ed731pdh]

Sounds like a 40 amp 3 phase Eurotherm module could be in order for speed control.

[Yorkie]

What a super job they've done in regrinding those beds Colin. The capital investment in all that huge machinery must be staggering, as well as the ongoing cost of running the factory. It's quite heartening to know that such places still exist, along with the skills base. It helps put the price of the work into perspective.

Old lathes can be a money pit - one thing leads to another. I was offered a smallish one recently for under £100, but it had clearly been abused, with hammer marks here and there and several teeth missing off gears. It had lots of change-wheels and tooling, and would no doubt make a nice restoration project for anyone with time on their hands, but that person isn't me. It's going to auction and will be interesting to see what it fetches.

I have a chum who is a model engineer and runs a small engineering business from home. He tells me that for mini lathes, the ones sold by Arc Euro Trade are held in high regard, and as soon as they come into stock, they sell out immediately:

http://www.arceurotrade.co.uk/Catalogue/...Mini-Lathe

Best of luck with the rebuild and paint job Colin!

[Yorkie]

I was one of the first in the UK to install this 3 phase system and it is brilliant. I'm a mechanical engineer so playing around with this amount of electricity was a major challenge; I'm not skilled in electrical work but hopefully I know what not to touch. I've posted the link before but here it is again;

http://unique3phase.com/

When I was searching my BVWS Bulletins for Gary's excellent article on making dials, in which his HMV650 silk screened dial featured, it was in the Autumn 2009 issue, where I also I came across your article entitled 'Unique Three Phase' Colin. Crikey, what an ambitious challenge that was, but what a superb result! I've seen that hefty transformer in action and it certainly does the business, but it all looks far too scary for me - I'd wimp out at the switch on stage for fear of taking out a sub-station and plunging the district into darkness

[Retired]

Hi,

Thanks Paul; 3 phase speed control is a bit too ambitious for me but I don't need it as my dust extractor is fine on fixed speed and my big Startrite Volant bandsaw is 10 speed.

It's such a pity these huge machines are becoming rare now David and the skilled operators tend to be near retirement age; in fact Robert Skinner who owns the company is retiring this Christmas but the new owner will continue with the work.

I fully agree with you David regarding taking on a lathe to restore. It is a difficult task and can prove costly; I recently sold a lot of my vintage radios and a number of my machines to finance these Myford restorations. Such work cannot be done quickly so you did right to let the lathe pass by; I don't have enough common sense to do the same.

My guardian angle died when I was born and I've done everything the hard way ever since. I never expect any of my restorations to be straightforward and so I'm not disappointed with these lathes. So far little is going to plan. The lathe as bought was very poor then "van man" let me down leaving me to transport the beds in the car. This afternoon I went into the garage with the intention of degreasing the newly applied etching primer which I did but whilst masking the newly ground ways I wasn't too surprised to find one of the "V"s had been missed by Robert. I wrongly assumed the beds had been fully ground as agreed.

I'm not even annoyed and have not informed Robert of this and don't intend to either. I just can't be bothered heaving this bed round any more transporting it once again to Halifax. I intend to hand scrape the saddles so at the same time I'll hand scrape the V.

I'm not kidding about our weather in fact I was amazed that I could spray both beds with etching primer when I did. Now that I wanted to experiment with spraying synthetic enamel for the first time the weather ensured this did not happen as it put down hailstones and was windy. This meant I couldn't open the garage doors to get rid of the fumes and the wind would had rendered the paint surface anti-skid. Again it didn't bother me because both beds are now looking much better with their first coat of green enamel applied by brush. I'll let this enamel dry for a few days then give a second final coat possibly by brush because Bron has just informed me snow is forecast. Problems are there to be solved and I'm getting used to solving them!! To put it politely the weather can get stuffed.

Thanks for your kind comments about my 3 phase system David; I enjoyed demonstrating it to you. Yes it even worried me when I was trying to establish the primary turns; this 3 phase transformer is rather larger than an output transformer in fact it takes two strong guys to lift it; the primary is wound with household 2.5mm insulated conduit wire. Following the instructions I experimented with the primary winding to get it perfect but during this experimentation I kept tripping the 30A breaker which as usual was done mid winter therefore knocking the central heating off each time. With patience and taking my personal safety into consideration I eventually obtained 1.5V per turn on the primary with the transformer idling at 0.8A. It was most interesting to find I could wind the primary then power up without having to wind on the secondary. I enjoyed doing this 3 phase but admit I found it a trifle worrying knowing a mistake could have been my last. Perhaps I have a guardian angel after all?

Kind regards, Col.

[Radio Fixer]

Whats a "V" for the uninitiated?

thanks Gary

[AlanBeckett]

Attached are a couple of Sectional Drawings of the Bed of my Dalton 6.
It's not difficult to guess why the two angled bits are called 'Vs', although they are upsidedown. Actually, any 'sloping' bit tends to be called a V even if there's only one.
The Slideways, which needed grinding, are shown on the second.
Alan

       

[Retired]

Hi,

Thanks for asking Gary. Some lathe beds have inverted "V"s on the top sliding surface these are cast into the bed and ground to exact dimensions; the saddle slides over them with a matching profile; on these Myford's the "V"s are along each edge side of the bed; the top surface being dead flat but with a V along each edge they form a dovetail. On the saddle there is a matching angle to the front which is part of the saddle casting but to the rear adjustment is afforded by what is known as a GIB STRIP; this strip is also angled and it is the dovetail formed by the two V's which locate the saddle allowing it to slide the full length of the machined "ways" with great accuracy. The GIB STRIP on these Myford lathes is adjusted by four machine screws fitted with locking nuts and once adjustment has been made the GIB is secured by three locking nuts from beneath.The ways are ground to very fine tolerances and many are hand scraped; in hand scraping a guide of 25 points to the square inch is the usual standard; the tiny hollows between the points aid lubrication.

As the job progresses I'll add a lot more detail regarding this together with pictures but I hope the picture of the rough drawing helps to clarify what I'm trying to explain. The arrows indicate the V's which I believe to be 60 degrees.

It is easy for those of us who own lathes to take these things for granted so I'm pleased you asked the question Gary.

Kind regards, Col.

   
Basic cross section of Myford lathe bed.

[Paula A]

I have done some turning way back.. I know what these bits are and can visualise them 30 years on and know what and why. Somebody been "casual" with a hammer again have they to cause a need for regrinding? I remember we had very similar pair of Myfords at school.. College used much larger turret and whatnot. I wasn't very interested when I was 16, and after a year turning out the same spindles day in day ouit on piecework I was more than happy to see the back of a lathe and an engineering works and go off to be a film maker... and ended up somewhere that is still to this day quite hard to completely get my head around

Thanks for such a clear explaination