Member postings for Martin of Wick

These are all really useful tips that I will keep in mind for the future, but for any of them to succeed, I think you need to have some degree of parallelism in the jaws to start with!

Using a bump centre to attempt to address the issue was quite entertaining. With the jaws set semi tight the topslide and toolpost would flex and twist in the most alarming manner. Slackening off the jaws to allow the work piece to move would get the axis OK at the bump, but everywhere else on the bar would be out of true.

I am certainly not an uber-perfectionist (slipshod and cavalier would be a better description), so could have lived with 4 or 5 thou axial drift over 4 inches, but not 30 thou!

I had been using the 4 jaw in an attempt to be a little more rigorous in my approach and working on short pieces, all seemed to be going OK . The issues only became apparent when working on the spindle for the lathe handwheel, a longer piece that needed internal and external concentricity on re-chucking to drill, thread from both ends etc.

Same problems showed up when mounting 3 inches of 45mm steel bar to skim a piece for the clamp fitting - and even setting the working end to true, the chuck end would precess and it would go out of centre with the lightest skim.

Thing is, until you examine the jaws in detail, the chuck looks quite good - the jaws are a good fit in the slots and the movement is smooth. It is just that the jaw faces have not been ground properly. If the chuck had been second hand, I would have attributed the problem to someone having attempted a bit of casual, freehand jaw grinding for personal amusement. That is how bad the clamping surface of the jaws are. Strange as the 3 jaw chuck from the same manufacturer was outstandingly good.

I shall give the vendors a call on Monday to see if they can help.

Thanks for all the feedback and some very good advice.

I didn't want to blame the tools, so was kind of in denial about the possibility of the chuck being bad ( 4 jaw came with new machine and had been unused until recently so had assumed it would be as good as the 3 jaw).

Subsequent to MG's and other posts I had a bit of an investigation. Checking jaws 2 by 2 clamped on some silver steel showed beyond any shadow of a doubt the jaws were absolutely diabolical. Not only was the grip wobbly and insecure in the plane of the pair of jaws, but clocking the steel bar showed 20-25 thou off axis over 3 inches for one pair and the other pair could be set at almost any position you like, none of which gave a true axis.

Checking against a backlit straight edge was utterly disheartening - some jaws were convex, some hollowed, others had uneven teeth (serrated jaws). A new chuck!! If you wanted to make one as bad as this it would actually be quite hard work Doh!.

Other parameters like spindle TIR checked out at half a thou and half thou wobble on the spindle plate mounting which is bit disappointing but probably OK for a CML. Slightly concerned, for as I recall there was almost undetectable run out when I unboxed the new machine 18 months ago and it has been fitted with angular contact bearings.

So replaced what is now a large heavy paperweight with the original 3 jaw that I had recently spurned for having a totally outrageous 1.5 thou TIR and an axial drift of half a thou over 6 inches. Incidentally, both chucks are from the same 'no name' manufacturer (orbiting stars brand from the logo!).

A new chuck is called for I think. I quite like the idea of attempting to re-grind but is a bit of a scary prospect, although difficult to see how any remedial action could make this specimen any worse..

At the moment all I would like to do is throw the chuck at the head of person that QA'd it. Interestingly, the gaudy check sheet that came with the chuck gives expected parameters for run out on the various planes and axis, but has no data for a chucked test bar (like the 3 Jaw has). Why is that I wonder!!!

Thanks again to all for your help.

How is one supposed to set either stock for machining, or work undergoing second operations to run to a true axis within the 4 jaw chuck?

Radial setting - no problem I can set up to les than half a thou TIR, on a point but move the DTI out or back along the work and the run-out can quite literally go 'off the clock' especially when working with 4 or 5 inch stock.

There must be a way to set up for a true axis but I can find no reference to this problem in my meagre stock of literature. It is causing me some stress at the moment as no amount of nudging, thumping, hammering of the work piece or praying and swearing seems to be helping me set the work to run true down the axis. When I set zero TIR adjacent to the chuck the tailstock end goes out of true. If I clock in the tailstock end, I find the chuck end is now off centre. OOOF!

I thought that one of the great benefits of the 4 jaw was the ability to clock in a repeat setting - but how is that achieved without some reliable way to get the axis running true?

I clearly have a major learning gap here, so would be very interested to learn what approach others have used.

If you feel the need to use He-Man insert style tooling on the 7, the easy way is to just determine the shim requirement and superglue the required thickness of material to the bottom of the 12mm tools so they can be directly off the top slide with the original clamp fitting. Simple and quick.

Get some 10mm tooling for use with a quick set tool post. No prizes for guessing which tools you will use most of the time!

If you are desperate to use 12mm tooling in a quick set format, then some people have adopted the expedient of milling down the top slide to suit. Wouldn't be my first choice ( neither would milling the bottom od the 12mm tool because, er, um, it wouldn't be a 12 mm tool any longer).

|On a similar thought can anyone explain how a hydraulic ram works ?

It is based on using the surge pressure or transient caused by the kinetic energy release delivered by the instantaneous stop of a moving body of water. Also known as water hammer to anyone with old plumbing who has fitted an instant cut off tap. The 'clunk' that you may hear or feel through the house on slamming the tap shut is a pressure transient that can be many times the ambient pressure in the system. If you are experiencing this frequently, I suggest you get it sorted before you find your compression fittings starting to leak. (or not find until too late as in my case)

T hydraulic pump functions as water under some sort of pressure flows out of the waste valve of the pump, the fluid drag then shuts the 'waste' valve triggering a positive transient that opens a non return valve (nrv) on the delivery pipe and moves a small quantity of water up the delivery pipe.

Milliseconds later, the reflected negative transient causes the delivery nrv to shut and the waste valve to open allowing flow through the 'power' section of the pump again. The process repeats ad infinitum.

At each pulse, only a small volume is moved, but the process can continue endlessly as long as the flow and pump internals are maintained so over time domestically useful volumes can be moved.

'Stonishingly low tech, but very effective, however in the complex and demanding world we live in they are of limited application these days.

If you have a stream at the bottom of your garden, and wanted to move water up hill to storage at the top of your garden at practically zero cost, this is the device for you.

Siphons are a practical solution for rapid drain down in situations where it is clear there are no valve arrangements to discharge water in quantity.

A company I used to work for employed just such a mechanism to supply the transmission pumps, for circumstances when the usual draw off valve arrangements were not available (usually due to statutory reservoir inspections). Volumes could be maintained at up to 80 million litres per day via an 18 inch diameter siphon - limited by pump capacity and need to maintain reasonable suction conditions to protect the pump impellers.

If the calculation above is correct, 500 gallons/s approximates to 190 million litres per day, factor in a few losses and say 150 Ml/d should be achievable.

Compare that to the current rate of pumping - approx. 96 million litres day according to BBC (not clear whether this was the rate of pumping or the net water removed).

I suppose there are practical issues with sourcing and handling large diameter pipe quickly, but I would have thought the water companies or their contractors would have material available.

After the Rotherham dam incident, we were all told by our political masters to determine the cost of remedials to emplace rapid drain-down arrangements in critical infrastructure that did not have appropriate facilities. When the great and the good saw the cost, they turned white at the gills and ran for the hills.

As I recall we did consider siphons, but these were not put forward on the grounds of aesthetics - serried ranks of blue plastic pipe snaking over the dam was the issue, so they said...

For possible raiser, see **LINK** for myfordboys interpretation. Although his is designed for a ML10, you could try asking if he would be prepared to flog you a casting that you could adapt for a 7.

I would have imagined that T10 timing pulleys and belt would be preferable to gears for a smoother drive - and no need to run in reverse. Just as easy to gear down to suit your intended use.

See also Skoda Rapide - a more recent version of said Renault.

If you attempted to corner the Skoda at the speed of a front engine car, you would find yourself being rapidly overtaken by the rear end! At motorway speeds, there was an uncomfortable hovercraft feeling caused by the front wheels were barely in contact with the road.

Thankfully got rid of it after only ten days ownership, much to my relief.

7 in. swing over bed 9 in.  in the gap

Barely 1 1/4 in. (31mm) horizontal  in gap between faceplate and bed on a 7

Just over 1 1/2 in. on S7

Edited By Martin of Wick on 02/08/2019 17:04:28

Edited By Martin of Wick on 02/08/2019 17:06:35

| it's not far off the price of a brand new one. Will certainly keep it under consideration though.

Yeah, but no but, yeah but.... look at what you are getting - slotted cross slide, the crappy plastic headstock gears replaced with metal, decent tool holder etc. .

Not an agent for the vendor, but if I didn't already have that type lathe, I would get it in a heartbeat. At least some of the worst issues of 7x14 have been addressed. Surprised it is still available.

| I much prefer slightly more scale looking engines....

try this site, **LINK**

The de Waal plans look a little confusing to start with, but are ok when you get used to them, plenty of scope available and you can scale up or down as required.

Ben,

the ubiquitous mini lathe is quite capable out of the box for a swing of only about 6 inches. I know they claim 7 inches but in actuality, the limitations of the cross slide mean that it is very difficult to position the tool sufficiently outboard for the full quoted diameter. Just warning you!

You can sort of work around it to some extent by mounting tools sideways, but it usually results in significant overhang. Other solutions are available to modify the cross slide to increase the full range of movement (and top slide to).

The other prob, is you may want to use the lathe for milling, and the cross slide of the bog basic 7x12 is not slotted and does not offer any mounting options. You will need to make an adapter plate for attaching a vertical slide or angle plate - I say this because your limited centre height may be further reduced by such an adapter. You could attach directly to drillings in the cross slide, but it is a rather flimsy component at best, best have a sacrificial plate to preserve the integrity of the supplied component.

However, where there is a will... on my old ML10 which could only swing 6 inches, I made a spindle raiser with a 2 inch lift which allowed diameters up to 10 inches to be (carefully) machined. The truncated myford nose spindle ran in AC bearings in a billet of aluminium, driven from the lathe spindle via a taper with M5 timing pulleys. I think I geared the driven spindle to about half lathe spindle speed. It may be a solution if you want to stretch the capacity in future.

Del

PM sent

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

This subject has been pretty much done to death.

Unfortunately, Myfords have generated a cult following and like all cults, the followers are blind to their own folly. As a long time Myford user, the general American view of them as shoddy and lightweight is closest to reality (possibly excepting the ML10 which is in a quirky class of its own). They didn't begin life this way back in the day, but because used machines are now so old and have been through so many users, each inflicting their own peculiar abuse, the majority of these machines are now in need of significant and expensive overhaul and are often a disappointment to enthusiastic new owners high on the Myford hype.

Because of where you live a used Myford is a high risk proposition unless you are prepared to afford a fully reconditioned machine direct from Myford. Otherwise, purchasing spares from the UK will be an expensive proposition. What will you do if the bed needs re-grinding? Remember that what is usually on the market at the prices you quote is getting on for 50 years old. Would you want a 50 year old car as your only mode of transport?

The question you need to answer is do you want to spend all of your time coaxing a piece of engineering history back into a usable condition, or would you rather just get on with some model engineering.

It is simply a question of how you see risk and reward - the probability of getting a quality used Myford is much less these days than the probability of getting a new, fully usable eastern machine with dealer backup that you can just plug in and go.

But if you feel a need to join the cult, don't let my prejudices deter you!

If you are getting started with the mini lathe, there is also quite a helpful machine specific guide / manual available here:

**LINK**

if you have downloaded the Clarke manual, on page 26 there is a photo that shows the position of the moving steady on the saddle to the left of the cross slide (when viewed as if using the lathe)

If you look at the left side of the saddle, you will se the two threaded holes (they may be filled with swarf! Attachment is by two M6 bolts (they are M6 on my minilathe - may be different thread sizes on other clones)

Currently in use S7B, Sieg C3 clone, Sieg C1, EW(intermittently) Verdicts below..

ML7 OK but high maintenance

M S7B better than ML7 but still a bit of a Diva and oil puker, generally a joy to use

ML10 robust and accurate but rather quirky no tumbler reverse, coarse feeds , odd centre height

C1 good for small stuff but really needs a more powerful motor - full nut a pain

C3 clone - has many issues, but quite good - now my goto lathe for basic work, can be abused without complaint!

EW Stringer 2 1/2 current restoration project - fragile and slow - full nut again not much between this and C1

No need to be frustrated. For the work you aim to do, any of the machines mentioned will be perfectly adequate, the only difficulty, if not buying new or fully reconditioned, will be machine condition.

Although not my first choice, if you want, a good condition Myford will be a perfectly satisfactory machine and has the advantage of being commonly available on the secondhand market and spares support from the current marque owners.

With patience you should be able to find one in a reasonable condition to suit your budget. You are paying a bit for the name but the cost of eastern machines has increased by about 30% in the last few of years so the differential is not as marked as it was.

On the subject of accessories, someone did mention a vertical slide +1 for that- increases the utility of the lathe by enabling light milling activities.

Usual advice for s/h

avoid e bay (useful for general research and having a laugh at some of the dogs for sale!)

don't purchase without viewing and testing (see threads for common problem areas to look for on Myfords)

don't worry too much about the cosmetic condition (paintwork) -always check the fundamentals

be prepared to walk away no matter how far you have driven!

keep back some of your budget for remedials (ie replacement of a bush or feednut etc)

As a Myford owner, my advice is don't bother with Myfords - they have had their day and are only of interest to vintage machinery buffs. You used to be able to get an entire workshop for the cost of some clapped out piece of junk, but now the pound is approaching Argentinian peso status, that may not be the case any more.

However if you must go down that route - don't buy a cheap one from any source - it will be dog. Ask me how I know.

If you buy a dear one, it may or may not be a dog, but it will certainly need some sort of attention.

Only purchase if it comes with correct 3 and 4 jaw chucks, full set of change gears (or reduced set for models with gearbox), manual, faceplate, catchplate, centres and drill chuck This will be the minimum set of accessories to which you will need to add the cutting tools of your choice, either HSS or carbide insert tools.

I suggest you improve your skills by making things like steadies and toolposts etc.

You can get a range of common accessories and most consumable spare parts from new Myford - at a price. You can also purchase reconditioned machines from them, so they claim. You could also ask them how much longer they expect to remain in business selling spares to a shrinking market and 'new' machines at 10 grand a pop.

Most threading is done from the tailstock, a gearbox equipped lathe is not really necessary unless you foresee that most of your work is going to involve thread cutting. A machine with gearbox does not require a full set of change gears but may have a reduced set.

If your non gearbox purchase includes the full set of change wheels, you will be able to cut most imperial and metric threads (caveat, you may need 2x21 changewheels or a 63 to cut metric threads to a higher precision).

see WWW.lathes.co if not already visited for further info.

How comfortable is comfortable? I have my S7 in a space 48 by 36 inches but the motor end is accessible by being next to the doorway and to get the tailstock off, I need to slide it over the bench slightly. How close you can get to wall may depend on the motor size, but in my case it is the primary drive cover. I stand this about 3 inches off the wall so I can access the belt for speed changes.

Should I be worried and if so what should I be checking?

Yes,

When running the lathe for a period, check for temperature over the bushes, particularly the unit not using oil. Any warmer than blood heat needs investigating.

Check the bush that is losing oil and determine where the oil is going. If you see oil escaping from the oilite bush and dribbling down the countershaft leg, the oilite bush will need to be replaced before damage is done to the countershaft spindle. The bushes are cheap (shop around the online bearing resellers of buy at a premium from Myford), the spindle is a v expensive component.

Check the bearing that is apparently using no oil as detailed in above posts. A bush in good condition will not be using use much oil - perhaps a slight top up after an hour or two of running. If this is not the case then check the oilway has no waxed or solidified oil. If oilway clear, it is possible that oil has solidified in the pores of the sintered bush. In which case I would replace the bush for the reasons given in the above paragraph.

The bushes are replaceable without taking the whole countershaft off the machine, but you will need to make some pullers using threaded rods and tube and some dies (piece of ally turned to od of .75in with wider section aprox 15/16 to extract and insert the bushes. It is important to completely fit the replacement bush with an accurately turned .75 in pin when pulling the new bush in, if you don't, you may distort the bush and not be able to get the countershaft spindle back in again.

I have a similar problem - one bush is actually OK but since I have to take the spindle out, it is expedient to replace both.