Search Results for 'MyFord ml7 clutch'

[Nigel Graham 2Participant @nigelgraham2]

I fitted my ML7 with a Newton-Tesla set, which is electronics plus motor.

My version is just a straight swap plus finding a suitable location for the inverter/controller. If you tell them the machine they know which electronics to pair with which motor.

I say "my version" – I'll go by that to start with. You'll see why, shortly.

The lead from the motor has a special plug for the connector on the electronics.

The main lead is rather short, at least on mine, so I have to use a short distribution-board. That though is a matter of workshop geography so may not apply to yours.

I placed the inverter on the cabinet below the headstock, but that is in the way of oil and swarf so I made it a cheap-and-cheerful plywood shelter that sits in the chip-tray above it. It's there because although I am right-handed, the disposition of the controls is better for using left-handed on the inverter I have. In particular, reducing the risk of accidentally using the wrong Stop button.

'

I stressed that clause because the Newton-Tesla systems I subsequently bought for my other machines differ, by having two separate electronics units. Those do need more wiring – not difficult if you are reasonably happy with such work; but it is vital you put the right wire in the right place, of the mains lead and of the cable linking the inverter itself to the control "pendant". Which isn't really a pendant but a box with lugs for screwing it to a surface.

If the set you buy is of that pattern, put the inverter somewhere well out of the way of swarf and oil-spray, as it is not fully-enclosed.

That on my Harrison lathe is high on the wall above the tail end of the bed, with the controller just below it, still well clear of the muck. It also keeps me clear of rotating things – which can't be said for the rather dubiously-designed clutch lever a feature of the L5! Similarly with the set on a BCA JIg-borer – on the wall a bit above and in front of my shoulder when sitting at the machine. The set destined for the milling-machine will also be similarly elevated to a higher plane.

'

One thing to watch (having just given myself an expensive repair!)…..

If the motor is the type with open ventilation holes in its ends, fit a shield to protect it from swarf, unless your lathe already has that luxury. Turning some bronze, most of the swarf "corkscrews" were falling harmlessly to the front, and I failed to see one sneak round the rather inadequate shield, and enter the motor. The resulting short to earth did not hurt the motor but damaged the inverter. I can say N-T's repair service is prompt, but obviously equipment like this is not cheap!

While the motor and inverter were away I fabricated a complete back-panel and motor shield – I've put a photo of it on the "What I Did Today" thread.

'

Right…

Advantages? There are three, really.

– Very much smoother and quieter running than with the single-phase motor, which tends to make the cabinet (standard Myford one) resonate.

– Better speed control, especially for operations like screw-cutting up to a shoulder. By still using the back-gear, you can have everything moving at a less nerve-wracking rate.

– Ability to adjust the speed during the cut, as sometimes useful such as when noise or chatter may indicate wrong speed for the other conditions. Also when paring-off large diameters.

NB: 1. These motors do not like being run too slowly, and the warning colours on the speed control are for low as well as excessive speed. (Used in conjunction with the headstock gears, I can run the Harrison at about 60rpm with the motor still happy at nearly 1000 rpm.)

NB 2: Don't use the Emergency stop-button as normal stop. The makers warn its frequent use can harm the electronics.

Disadvantages?

I've not found any.

So, I hope this answers your query!

[Graham MeekParticipant @grahammeek88282]

Hi Will,

The travel to trip the clutch at the carriage, on the Myford, and the Hardinge I worked for some time was about 15 to 16 mm, from memory. The travel at the S7 and ML7 clutch units is 2.5 mm, the clearances need be no more than 0.25 mm. The Operating lever stops moving as soon as the Dogs disengage, and the ball bearing detent wants to be close to the neutral position, so that the Operating lever will snap into neutral.

Once set the carriage will repeatedly stop in exactly the same position and start in the same position. The only time these settings alter is when you set at a lower speed and then for some reason increase the spindle speed. As you rightly assume it is to do with Moments of Inertia, but once the settings have been reset at the higher speed the carriage will carry on as before.

I have always pointed this out when setting up the clutch unit in my articles to make those wary with VFD drives. It was something I found out while using the Hardinge which has variable spindle speeds.

Regards

Gray,

[Brian OldfordParticipant @brianoldford70365]

Posted by Nick Clarke 3 on 03/05/2020 21:00:21:

It is a dim memory, but wasn't one version of the Myford clutch the front brake from a Raleigh moped??

IIRC it was an after-market accessory for the ML7 made that way.

[HopperParticipant @hopper]

Tumbler reverse was optional, castings sometimes available to make your own. Geoff knows more about that.

Thread chaser dial on mine is a homeshop-made job. Not sure if Drummond ever made one themselves? I've never seen one in any of the old pics. A Myford ML7 indicator uses the same gear to engage the leadscrew so could be adapted possibly.

One handy thing is you can use the leadscrew dog clutch for screwcutting threads that are a multiple of 8. IE, 8, 16, 24, 32 and 40tpi etc. No need for a chaser dial. The dog clutch always engages in the right position for these threads. It's a super-handy feature that is sadly lacking on Myford's later lathes. I miss it every time I use my ML7.

 

Edited By Hopper on 02/05/2020 11:40:55

[Andy JervisParticipant @andyjervis27747]

Posted by Steviegtr on 01/05/2020 18:41:54:

Looks like a Myford ML7 without a clutch & quick change gearbox. Look at the front left of the bed around where the plastic bag is. You will find a No then look up on myford site & that will tell you the year of manufacture. If no number there then look at the right rear behind the tail stock on the bed. If it is not worn & all seems right they can be worth anything from around £650 upwards. I paid Considerably more my similar model.

Steve.

Edited By Steviegtr on 01/05/2020 18:44:43

Thanks so much Steve the one pictured is advertised for £700 ??

[Andy JervisParticipant @andyjervis27747]

Posted by Steviegtr on 01/05/2020 18:41:54:

Looks like a Myford ML7 without a clutch & quick change gearbox. Look at the front left of the bed around where the plastic bag is. You will find a No then look up on myford site & that will tell you the year of manufacture. If no number there then look at the right rear behind the tail stock on the bed.

Steve.

Thanks Steve would it be ok for a beginner looking to move up to a larger machine from a mini lathe ?

[SteviegtrParticipant @steviegtr]

Looks like a Myford ML7 without a clutch & quick change gearbox. Look at the front left of the bed around where the plastic bag is. You will find a No then look up on myford site & that will tell you the year of manufacture. If no number there then look at the right rear behind the tail stock on the bed. If it is not worn & all seems right they can be worth anything from around £650 upwards. I paid Considerably more my  similar model. 

Steve.

Edited By Steviegtr on 01/05/2020 18:44:43

[Howard LewisParticipant @howardlewis46836]

If you read the various articles on updating Myford ML7s from narrow to wide shear location, you will see pictures showing that in many cases, of used machines, the saddle does not make overall contact with the bed. In which case, it could be liable to wobble in a vertical plane.

Also, to enable the saddle to move along the bed, it must have clearance.

So if there is any clearance between saddle and bed, there is the chance that it it may change (very likely if the bed is twisted ) and so introduce inaccuracy.

Laying the level so that it rests on the bed minimises the number of parts involved and sources of error.

The more directly that the measurement can be taken reduces possible errors.

Not applicable in this case, but think in terms of drilling ten holes in a strip of steel, with Centre distance 1.000.

If you dimension every hole from one datum point, then every hole will be within 0.005" of the nominal position.

Dimension to a +/- 0.005" tolerance on the individual centres, and the last hole one could be as much as 0.045" more or less than the nominal 10 inches.

The moral is: minimise the number of dimensions involved. So work direct off the bed, because that is what you wish to measure, not in terms of thous or microns, but graduations on the level..

You would not try to measure the backlash in your cars transmission by measuring an angular movement between the road wheel and the flywheel

If you did, there will be clearances in both ends of the drive shaft, gears in the differential, gears and their splined shafts, gear to gear clearances, and between the splines between first motion shaft and clutch centre plate.

But you would not know if there was an excessive clearance at any one point..

As the amateur radio fraternity say, KISS "Keep It Simple Stupid"

As an Engineer in a Quality Department, I was trained to think logically, and to measure as directly as possible.

Howard.

[HopperParticipant @hopper]

You might try sending some pics to Tony at Lathes.co.uk if you can't find it on his site, He may be able to identify it.

Interesting old machine, especially the combination top/cross slide set up. Good to see the dog clutch on the leadscrew. Very handy and something Myford should have fitted to the ML7 etc.

[Mike PooleParticipant @mikepoole82104]

Posted by Brian Wood on 07/02/2020 15:41:56:

Dave,

The ML7R is a hybrid lathe with an ML7 bed, fitted with the ML7 cross slide/topslide, but a Super 7 headstock and tailstock.

I don't imagine Myford made a different bed for the S7 but KWIL's point on matching the centre heights between headstock and tailstock is relevant and it might pay you to fit both.

Regards

Brian

to be a nit picker the ML7R has the Super 7 bed, headstock, tailstock and saddle/apron of the old non power crossfeed Super 7. The economies were made by fitting the cross and top slide from the ML7 and not fitting the clutch, the countershaft is unique to the 7R but can be replaced by the Super 7 clutch version. I think the idea was to consolidate the bed across the range and delete the old ML 7 bed and 5/8” leadscrew. No doubt an ultra nit picker will find something I have forgotten. Just remembered the leadscrew handwheel was also deleted on the 7R

Mike

[Howard LewisParticipant @howardlewis46836]

Any machine, if it is looked after, and not abused will last for ages. A friend is still using, as far as I know, a Drummond dating from the early 1900s. I know of several Myford M types that are still being used by happy owners.

Those machines must be 70+ years old. The ML7 was launched in 1947 so there must be many that are 70 years old and still functioning satisfactorily.

I started with a ML7, without a clutch, but bore in mind the comments about electric motors not liking the heating effect of the current inrush of frequent start ups. My lathe had at least one previous owner, judged by the wood dust around it. The motor never showed signs of damage from the number of starts that I gave it.

It was replaced after several years with a Chinese 12 x 24 lathe, to have a larger Mandrel bore than 2 MT.

After over 16 years that seems to be as good as new, apart from the cosmetic aspects. There have been a very few small problems; but nothing that could not be cured quite easily and quickly.

Remember the adage about Good Tunes being played on old fiddles!

Misuse can ruin a new machine in as little as minutes. Care, and use within limitations, can keep a machine working accurately for many years.

If you think about buying any used machinery, ensure that all the functions work, and that it is not worn or damaged, and all the accessories that should be there, are. CAVEAT EMPTOR!

Howard

[David James JennerParticipant @davidjamesjenner99025]

Bought my very first Myford a ML7 with stand, clutch and Quick-change gearbox just before Christmas 2019.

Came with the manuals for the lathe and gearbox, a promotional pamphlet and a couple of books one by Mr Westbury and one by Mr Bradley.

A collection of disassembled parts, so an interesting project!

Looks to be all there, not sure of the age as the bed is well coated with grease preservative.

Just need to find some time!

I expect I'll be posting some questions here in due course!!

Dave J

[Nick Clarke 3Participant @nickclarke3]

A Myford ML7 can (depending upon condition) be an excellent lathe but can it please be looked at in the cold daylight of its history.

It was designed in the later years of World War 2 and put on the market in 1947 – a long time ago! The comments about steel are not necessarily true, and in the case of a lathe where the major proportion of its construction is cast iron or zinc alloy probably irrelevant as well. Like many other products introduced around that time the choice of materials was probably decided as much by what was available in immediate post war years as by engineering need.

If you read the review of the Myford Super 7 in ME Jan 15 1953 it clearly suggests that the ML7 was designed to provide the best lathe that was affordable and the Super 7 was introduced to try to address some of those compromises. It specifically mentions the clutch as being necessary for 'a lathe running at high speed' suggesting that its inclusion is less important for a ML7 with its slower top speed.

Many Myford lathes are now of pensionable age and unless preserved in good condition may well be past it – I can think of two I have access to now – one has a bed worn to the state that there is 1/8th swing on the saddle when cutting and another with a parallel bore to the nose of the spindle because that was necessary to accommodate a job in the past.

The basic technology of a Myford ML7 is 19th/early 20th century while that of Chinese lathes seems to be more (but not that much more!) recent.

A Myford or similar lathe can be a joy to use – but in the same way that I find my ridiculously expensive Leica film camera more pleasant to use than a far cheaper digital SLR – but the quality of image doesn't differ in the same way. Similarly comparing a Myford with accessories and motor ready to run with a Chinese lathe at a half or a quarter of the cost may not produce better work. I certainly could not have afforded a Myford lathe for the price of the new Sieg machine I bought – and restoring one I could afford to accuracy would probably have been beyond my skills.

Please don't think I am against Myford lathes – but their age and older design, and the times they were designed for must count against them today, except in a few very well cared for or little used examples.

[Don CoxParticipant @doncox80133]

My 1949 ML7 came without a clutch and was fitted with a 1/3 hp (I think) Hoover motor which I believe to be the original one fitted from new. The lathe was quite tatty when I collected it (cost was £450) but it had no insurmountable problems when I came to pull it apart. I rewired the motor switch set up, it now has an NVR wall mounted switch and a Dewhurst forward,/stop/ reverse switch mounted behind the front face of my home made copy of a Myford hexagonal stand.

I've had it for about 12 years now and have never noticed the motor to be over heated, I frequently use the belt tensioner as a clutch to limit the number of start ups and the Dewhurst switch stays permanently switched to forward.

I bought a Tri-Leva conversion to go on it a few years back, but I then chanced across an S7 (1963) on eBay, with a genuine hexagonal stand, a gearbox and close to home, for £950. So now the Tri-Leva bits remain unused in their box and the ML7 does a bit less than it used to. The S7 now has a VFD motor setup and, of course, it came with a clutch. I tend to use the lathes in turn to avoid having to change tool holders, chucks etc for different jobs, I don't find not having a clutch on the ML7 a major disadvantage.

[JourneymanParticipant @journeyman]

Posted by paul humphries on 11/01/2020 09:57:25:

Thanks Paul, I presumed that modern brushless motors were more tolerant of stop start but maybe not. I must admit the whole buying a lathe thing is quite stressful, especially at my sub £1000 budget. Decent ML10/ok ML7/new Chinese!!

Sorry Im going off topic but I think you have answered my question. Might give the ML7 a go.

Paul, make sure you check out the ML7 carefully before parting with cash. If possible see it running and working. If you are not sure what to look for try and find an "expert" to go with to look at the lathe. Many old Myfords have been nurtured equally many have been abused.

Brushless motors are essentially DC and use fancy electronics to make them go round. Not particularly comparable to an old single phase AC induction motor, which is also brushless, that uses just the mains 50Hz to cause rotation. If upgrading the motor the way to go is VFD and 3-phase motor but you are adding a few hundred quid to the bill but solves speed and clutch in one go (can of course be retro-fitted if the basic lathe is good).

John

Edit: Clarification

Edited By Journeyman on 11/01/2020 10:36:27

[Swarf, Mostly!Participant @swarfmostly]

Hi there, Paul,

To answer your concluding question, we would need to know the number of ML7s with clutches as a percentage of the total ML7 population. It would be an interesting subject for a poll. I suspect that the answer would be significantly less than 50%. It would be ridiculous to conclude that the clutchless ML7s are not 'really usable'.

I ran my own ML7 quite happily for several years before fitting it with a countershaft clutch. (I cheated – I did not buy a complete clutch but just the parts I didn't fancy making. )

With respect, your phrase 'flat out' is missing the point – the motor is best cooled and hence happier when it is running at full speed. It is the inrush current that flows in the motor start and run windings as the motor runs up to speed that causes the most stress. Also, the centrifugal switch will accumulate deterioration with each start event (e.g. contact arcing & fatigue of flexures) . However, one would hope that a conscientious motor designer would design for these effects.

The countershaft clutch does ease the burden on the motor but, in my opinion, it is an enhancement rather than an essential. I would not be so willing to acquire one at today's prices as I was back in the 1980s when components were available as spares from Beeston Myford.

Best regards,

Swarf, Mostly!

[Paul KempParticipant @paulkemp46892]

I would hazard a guess there are more Myfords out there in the wild without clutches than there are with. My ML7 hasn't got one and it's never been an issue. No different to any of the other lathes that are not fitted with clutches surely?

Paul.

Details wanted for Graham Meeks Clutch but retaining rev. cluster

[HopperParticipant @hopper]

Posted by Howard Lewis on 07/10/2019 18:54:11:

George has summed it up pretty well.

The peculiarities of the M types were :

To save confusion, albeit at risk of my sounding like an overly pedantic twit,  please note that ML1 – 7 are not "M Types"

The M-Type was a completely different lathe, made initially by Drummond and taken over by Myford during the war because it was considered a superior machine (for war purposes) to the ML1-4 models made by Myford.

After the war with the advent of the cheaper ML7 Myford, followed by the Super 7 etc, these became known as 7 Series lathes by some. But never as M series or M types. The M-type died an honorable death circa 1948 or shortly after when the lower-cost ML7 flooded the market.

If you search lathes.co.uk for "M Type" the whole intriguing saga is chronicled in detail.

Back to the OP's lathe and it looks like a good 'un from the pics. Has some serious upgrades such as the overhead v-belt countershaft, a clutch and what looks like some kind of indexing disc by the heashdstock pulleys. And is that a 127 tooth gear on the leadscrew for metric thread cutting? Either that or a very fine feed rate. Nice.

Edited By Hopper on 15/10/2019 08:09:20

[Martin of WickParticipant @martinofwick]

To answer your specifics:

My S7 dates from 1978 and that has the non embossed belt cover with simple ally plate showing speed combinations and tacky plastic logo on the headstock castings – standard for the later lathes.

Don't know what year they began this, obviously done as a cost cutting exercise and probably denotes the exact point at which Myford's glide path to oblivion began.

Compared to the basic ML7 The S7 cross feed has a much more robust bed with larger leadscrew and is in the wide-guide configuration (carriage bears on the front and the back shear). Also cone bearing in the headstock and countershaft clutch. Bigger and stiffer al round. There are some variants ML7Rs that are essentially S7 without cross feed and clutch and with the weaker ML7 saddle cross and top slide. Some ML7s have retro-fitted clutches. For info on all the variants check out lathes,co.uk.

Nothing wrong with the Mk1 S7 apart from the fact it is getting on for 70 years old. In some respects the bearing lubricator is much better than the Mk2 felt wick type,although prone to leakage from the sight glass. Would not recommend that you purchase any lathe with a view to replacing large and expensive components such as headstocks.

The condition of the paintwork is not necessarily a good guide to the mechanical condition of the lathe. PM me if you want a check list for used Myford tests.

Trouble is for a fully detailed mechanical test you will need some basic test equipment and some of the tests are quite intrusive, some owners are reluctant to allow such a detailed survey.

However, there are some basic checks that will tell you whether you need to walk away. Look at Myford Ltd. site and get an idea of the cost of the common refurb items such as feeduts, feedscrews, leadscrews bushes and bearings etc so you can assess how much the remedial work will cost you. For a significant number of machines, the faults will be legion, some are cheap simple fixes and some eye wateringly expensive.

 

 

Edited By Martin of Wick on 22/07/2019 16:20:15

Edited By Martin of Wick on 22/07/2019 16:28:07

Edited By Martin of Wick on 22/07/2019 16:31:39

Edited By Martin of Wick on 22/07/2019 16:32:12

[Mark RandParticipant @markrand96270]

Myford long bed ML7B with clutch that dad claimed to have bought for my 10th birthday in 1967…

Short bed ML7 basket case that I bought in 2000. Got Myfords to re-grind the bed and rebuilt the rest of it. Fitted an inverter bought from John Stevenson to go with a decent 3ph motor. Sold it in 2008 after I inherited the ML7B.

Dad died on Christmas Eve 2003 and I inherited the Myford plus a Hardinge DV59. Never used the Hardinge and it eventually got scrapped!

1952 Hardinge HLV bought in 2006. Rebuilt over four years, using the Myford to re-manufacture all of the apron gearbox shafts and gears. It is my current every-day lathe.

[Graham MeekParticipant @grahammeek88282]

Hello Robert,

I am unfamiliar with the DRO set-up so I cannot comment on this.

There have been a few additions to my original design to suit personal preference. The first being the ability to dis-engage the unit when desired. Using the original Myford tumbler lever location holes. This was done by Ken Willson, (KWIL), and several people I know have added this feature. I have no drawings of this, but I am sure a personal message to KWIL will get you the necessary details.

Another modification which has gone a long way to quieten the device down in use is the fitment of non metallic idler gears in place of the Phos Bronze ones. The materials used so far are as follows, Delrin, (Acetal), a Nylon graphite mix and my choice Tufnol. The flat woven material, not round. The latter is not good for gears as the laminations are running parallel to the gear teeth. Not perpendicular to them as in the sheet material.

The last modification I can think of is the addition of ball races in the idler gears. This mod was down to Phil Proctor and shown on the front cover of MEW which contained the ML7 version of the clutch.

I hope this helps.

Regards

Gray,

[Brian WoodParticipant @brianwood45127]

Mark,

Michael G has very likely given you the explanation, Tufnol gears must be made from fabric or better still paper lay ups so that they have strength in the radial direction. Rod form is made from rolled up material, useless for gear purposes, but excellent for insulation spacers for example.

Were these gears supplied in a properly sealed Myford pack? My thought here is that they were fakes that may have been passed on in good faith [or not of course]

I think from the speed of failure you were getting this can't be explained by pressure angle mismatch. ML7-R lathes with the S7 headstock were fitted with the 30 T spindle gear, tumbler cluster and the next 30 T gear all in 20 degree PA. This fact only emerged when Graham Meek was designing his reversing clutch to take the place of the 3 gears running in engagement with the 30 T spindle gear

I'm sorry you have had this setback, if you have the kit to make your own I will happily post you a suitable one inch thick blank to make two f.o.c Send me a PM if that appeals

Regards

Brian

[HopperParticipant @hopper]

Posted by Mike Crossfield on 28/02/2019 12:39:16:

Hopper

Dennis’s machine is a Super 7, but your last 2 messages appear to relate to an ML7.

According to the Myford website, the Super 7 countershaft bushes are 7/8 I.d. and 1 1/8 o.d. The lengths are not specified.

Mike

Ah yes. Larger shaft for clutch rod up the middle etc. Thanks for clarifying.