Lathes : Weak-Points

[Michael GilliganParticipant @michaelgilligan61133]

Prompted by a remark by Roderick Jenkins **LINK**  I thought we might try an alternative approach to the perennial 'choice of lathe' question.

Good as it is in most respects; any lathe will have its weak points, and perhaps highlighting these will be as useful as reciting the 'best features'.

Let me start with the Myford ML7R …

Despite its obvious strengths; a look at the cross-slide and top-slide feedscrew arrangements reveals that this is a light duty lathe. … Flimsy little die-cast nuts, with no adjustment for wear.

MichaelG.

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If anyone cares to join me in this investigation; let's please base comments on actual experience, not hearsay.

Edited By Michael Gilligan on 18/02/2016 16:50:48

[Michael GilliganParticipant @michaelgilligan61133]

… it’s only let down by […] …

[Brian WoodParticipant @brianwood45127]

The tailstock on the Model B 3 in 1 machines is a dreadful design with a narrow base fighting off the leverage from the over size height of it. There are other design faults too, but that is a glaring obvious one.

Brian

[JAParticipant @ja]

Late Myford lathes', and I suspect all Myford 7 series lathes, cross slides are not very stiff. They can tighten and even lock if items bolted to them are mis-postioned. I have found it wise to sandwich a 3/8" to 1/2" thick plate between the slide and such an item when possible to prevent this.

JA

[AjohnwParticipant @ajohnw51620]

The 3 in 1 isn't a myford. Maybe a mod will remove my post and the 3 in 1

John

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[JasonBModerator @jasonb]

I did not get the impression it was a Myford only thread so posts will stay unless Michael asks otherwise.

J

[JasonBModerator @jasonb]

My biggest niggle with the WM280 which also applies to the other colours of the same machine and this style of lathe in general is the chuck mounting method.

The backplate is retained by 3 nuts and washers that are accessed from the rear of the spindle flange which is quite close to the headstock and can be a bit of a pain at times but you soon learn to plan your work to keep chuck changes to a minimum.

I have noticed that the WM 290 now has a "keyhole" arrangement which means the nuts stay on te backplate studs and just nee dnipping up or loosening to change chucks. This could quite easily be carried over onto teh smaller 280 & 250 models. Better still some suppliers are nor doing a D1-3 or D1-4 fitting which I would happily pay a bit extra for.

J

[Michael GilliganParticipant @michaelgilligan61133]

Posted by JasonB on 18/02/2016 17:53:02:

I did not get the impression it was a Myford only thread so posts will stay unless Michael asks otherwise.

J

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Thank you, Jason … You are quite correct.

My idea was that it would be a 'reality check' on ANY lathe that might be in the running.

MichaelG.

[MWParticipant @mw27036]

This is probably a very well known problem but when i used the Sherline mini lathe, i was always irked by the fact that the chuck is "screwed" onto the spindle, meaning that the chuck could slip from time to time, i was going to say it could come off completely running in reverse but it cant even do that.

Michael W

[mechman48Participant @mechman48]

+1 for D1-3 & D1-4 fittings to be standard on Warco models 250 & up, I have changed the nuts & washers on my 250 V-F to flanged nuts, easier but still fiddly.

George.

[Michael GilliganParticipant @michaelgilligan61133]

Moving swiftly on to to the [smaller] Boxford lathes:

I only got-around to buying a headstock, but was surprised by the apparent fragility of the BullWheel; which is not only rather small in width, but slides freely on a narrow key. … and, if I understand correctly, spares are no longer available.

Also; the first gear in the screwcutting train is cut on the headstock spindlle … which makes replacement for wear or damage rather expensive !!

MichaelG.

[egaParticipant @ega]

"Flimsy little die-cast nuts, with no adjustment for wear".

This criticism also applies to the Super 7 but, in mitigation, they are cheap to manufacture and easy to replace. At the risk of uttering hearsay, other contemporary small lathes had their "nuts" cut direct in the slide.

On a general pooint, there is a clear distinction between weaknesses which can easily be remedied and those which have to be lived with. An obvious example of the former is the tailstock which has to be adjusted with a spanner. In the case of my Willson this was easily remedied with an adjustable handle.

Edited By ega on 18/02/2016 18:41:21

[Michael ToppingParticipant @michaeltopping17870]

The most annoying issue with my Warco 290 is the tail stock locking lever. No matter how I adjust it it will not lock consistently along the length of the bed. One day I will strip it down and re work it.

I don't find the chuck retaining bolts too much of a problem.

Michael

[RainbowsParticipant @rainbows]

Posted by Michael Walters on 18/02/2016 18:24:22:

This is probably a very well known problem but when i used the Sherline mini lathe, i was always irked by the fact that the chuck is "screwed" onto the spindle, meaning that the chuck could slip from time to time, i was going to say it could come off completely running in reverse but it cant even do that.

Michael W

Does anyone know what the smallest available cam lock fitting is? Most standards seem to have a minimal size of around 3" which is too big for the tiny lathes like the sherlines.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by ega on 18/02/2016 18:39:55:

"Flimsy little die-cast nuts, with no adjustment for wear".

This criticism also applies to the Super 7 but, in mitigation, they are cheap to manufacture and easy to replace. At the risk of uttering hearsay, other contemporary small lathes had their "nuts" cut direct in the slide.

On a general pooint, there is a clear distinction between weaknesses which can easily be remedied and those which have to be lived with.

.

ega,

With respect … My point was that the Myford is, by virtue of these nuts, a lighter-duty lathe than it might first appear.

It remains [in my opinion] a lovely machine, but I consider that its weak-point.

MichaelG.

[davebParticipant @daveb17630]

Myford ML7/ML7R cross slides are flimsy, they distort and move about, the saddle on the narrow guide versions is also a weak point. All can be lived with if in good condition and cuts and feeds held within reasonable limits. Myfords were never meant to be a heavy duty lathe, they were produced for a particular sector of the market and with the range of accessories, did what they were meant to do very well indeed. A late long bed version with gearbox and power cross feed is quite nice, the big bore versions also, both bearing only a superficial resemblance to the original ML7. Ultimately, the weakest point of the Myford lathe was its cost.

Dave

[BazyleParticipant @bazyle]

Posted by ega on 18/02/2016 18:39:55:

. At the risk of uttering hearsay, other contemporary small lathes had their "nuts" cut direct in the slide.

Contemporary? 1910 Drummond to 1990 Hobbymat. and v thread at that but they last ok too.

Most lathes – coarse threads on gibs making adjustment difficult and not enough of them.
Variable speed lathes that don't go below 200rpm.
Several modern lathes that have a screwcutting gearbox that is a messy mix of metric and imperial ratios so still requiring several wheel changes to get common threads.
3in1 machines – the very idea is a disaster designed to hoodwink motorbike nutters.
Most lathes – tailstock barrel ejects an inch before it should. – The body should be an inch longer.

[MWParticipant @mw27036]

I think any machine that comes with its own gear box and power crossfeed will set you back considerably. In some ways i'm not surprised as this is still considered quite a luxury accessory for most hobby machinists.

To be fair the quality of what you can get for your money is getting better by the year.

Michael W

[JAParticipant @ja]

Myford cross slide stiffness: the two steel blocks below the casting not only lifted it into the best position for the fly cutter but also allowed free and easy operation of the slide.

One minor niggle, not a weakness, about late Myfords is that to get to the oil nipple on the end of the back gear shaft the chuck has to be removed. Obviously the shaft only gets oiled between jobs. It has to be said Myford did like oil nipples. Every so often I wonder if I can afford ArcEuroTrade's oiling kit.

JA

[speelwerkParticipant @speelwerk]

Posted by Michael Gilligan on 18/02/2016 16:48:48:

Despite its obvious strengths; a look at the cross-slide and top-slide feedscrew arrangements reveals that this is a light duty lathe. … Flimsy little die-cast nuts, with no adjustment for wear.

MichaelG.

You can buy an updated Dutch version, Niko.

**LINK**

[alan-lloydParticipant @alan-lloyd]

The Myford 254 whilst being a lovely lathe to work with, does not have a clutch, what was Myfords thinking?

[Nigel McBurney 1Participant @nigelmcburney1]

All the lathes that I can fault with I have owned and used, and I was taught to use a lathe during my apprenticeship,the first was an EW 2 1/2 centre height, bought s/h when I was about 19 possibly one of the best small amateurs lathes, fault, the lead/feedscrew was in constant engagement with the nut on the saddle and was a right pain in the backside. later I could afford a new ML 7 as I wanted to build an Allchin, ML7 was £80 basic Super 7 was £120 basic , known design fault which I was prepared to live with was small spindle bore,the other which I did not realise was the top slide would not swing round easily for traditional method screwcutting,the tailstock barrel 2MTtaper bore is plain so cannot stop a drill or other tools from slipping so the bore gets scored. this also applies to S 7. Super 7 again spindle bore,too small, why they did not make a larger bore when the Super 7 was introduced I do not know it would have been easier then to have done it from the start and gone for 3/4 in clear. Colchester roundhead master,long bed Faults no clutch on the lathe I had, The proportions and dimensions of the slide ways of cross and top slides are too small,more suited to a 5 inch lathe,not an industrial 6 1/2. the tool post would visibly deflect when parting off ,or when taking heavy and course screwcutting, spoilt a good lathe and broke a lot of parting tools. Colchester student square head short bed with variable speed drive, Utter disaster, bought s/h in very good condition, the short bed was useless,the tailstock was always getting in the way,and the variable speed was a disaster for home use,no clutch, and when the lathe was stopped when in a high speed range the rotary converter could not take the load and the lathe stalled,comment from a well known tool dealer,variable speed Colchesters and phase converters are to be avoided,it was soon sold. Colchester Triumph superb machine no faults,except nowadays age causing problems as the chucks get heavier each year. Smart and Brown, late type plain precision lathe, superb machine,ideal for instrument turning, fault The superb precision large bore spindle taking 5c collets clear plus chucks was matched to a 1 MT taper silly little tailstock, the electrics (two speed motor) and starter were an absolute pig to get at in the 6mm plate welded base and they failed so I sold it ( at a profit) There you are that my experience since 1960

[AjohnwParticipant @ajohnw51620]

Bad luck Michael.

More normally.

The travelling steady on a Boxford isn't suitable for a modern tool post. It can be used but it's positioned for lantern holders so access right up to the chuck can be tricky.

It's reckoned to be the most economical South Bend clone but in real terms the only one that is "better" is the S&B Sable mainly down to some proportions and heftier lead screws if I remember correctly.

The spindle doesn't project out of the back of the change wheel cover enough so when swarf is pushed out that way to avoid getting it in the chuck it can get on the change wheels. If these have been set correctly for quiet running the stud gear shaft may bend if the gear gets swarf on it.

Only some models have spindle locks for unscrewing chucks. This can lead to bull wheels loosing teeth.

Some spare parts have to be bought from John Ward. True of other older lathes as well.

They were popular with pro home turners for batch work. Read most peoples normal working hours. Tough life for any lathe. They would normally sell on when bed wear reached a point where the taper was too excessive to meet what they needed to be able to do. Headstock bearings too.

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Any Chines lathe I have looked at – cross slide travel is always too short. That covers a lot. Also Wabeco 4000's.

The Wabeco saddle hand feed wheel size wise is a joke. It has the usual chuck fixings fouling problem but the spigot is a light drive fit into the chuck. The bolt heads can be used to lever it off with the same spanner so it's a good idea to use bolts to hold things in place. The spigot size is unique. The motor housing / cover prevents the saddle from going completely along the bed. This may hinder shallow face plate work without tool overhang.

Swarf will drop directly on the lead screw. The 4000 isn't supplied with a lead screw cover.

It uses 2 T slots at the edge of a thin saddle. Often these saddles can tend to distort and jam up if they are used to hold things down. They also hold the compound slide down and that has a lot of overhang as a result.

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There is something really weird about Viceroy head stock bearings. In one case, lathe not owned by me they wouldn't stay in adjustment. This one was near new. Bought new actually at a college. In the one I owned they just wouldn't adjust. These too can finish up being used by home turners, Mine had wear on the V's up by the head = 0.010 taper mostly due to that over circa 4" or so.

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Early Chinese 3 in 1. Nice finish turning, noisy gears, oil leaks and the worst general alignment I have ever come across even down to the hand scraped tail stock. Also not possible to turn up to a centre as the centre distance had been increased by 2" by removing the tail stock nose. A number of Chinese lathes have had this problem. Some may still have.

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Hobymat. Not bad as small lathes go. Pretty good really and can do accurate work. Dog clutch needed a file running over it after any serious amount of screw cutting. Often messed up by miss use of the push pull bolts used to set the saddle fit. This was the screw cutting Hobymat. They now do 2 models. Going on next owner ones that use a tool post where tools are clamped directly onto the top of the compound over pressure can crack the compound slide casting.

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Unimat. Fine for what it is. Pass on the model with 2 round rails. I just changed the bearings. They need that from time to time due to how they are used but the method works really well.

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Peatol / Taig. An amazing amount of work can be done on these if fully kitted out. Very accurate too even for roundness but eventually the head may bend spoiling it's alignment. It did on mine but perhaps I asked too much of it really. 6" diameter aluminium with the riser block on din't cause any problems. Fixing a cast iron pulley did. Turning one side of a V off and replacing it with a steel plate and recutting the side of the V. I've been told that this distortion will spoil the initial accuracy eventually what ever is done on them but bear in mind the initial accuracy is very high. They are also surprisingly rigid after a fashion so finish can be truly excellent.

I'd wonder about the motor they fit now. Mine had a normal AC motor. There was plenty of power available and a decent speed range.

John

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[AjohnwParticipant @ajohnw51620]

Part 2

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Myfords. Well plenty of use will result in more wear on the edge of the bed rails than many modern prismatic beds as the contact area is small – smaller than people might think as the wear progresses. This seems to cause more upset with things like parting off and even finish than some other lathes that use a similar arrangement.

I've hardly seen any plain bearing ML7's with shims still under the bearing caps allowing more rescraping as they wear and they are often worn going on the ones I have seen. Ok if some one can use a bearing scraper and keep the spindle level with the bed. Several people have mentioned that these lathes can drill a bigger hole than an S7 if that's head stock bearings are set correctly. Many people seem to have problems once they play with these. The person I bought my ML7 from had overtightened the countershaft belt to try and mask the problem but it still becomes apparent with various depths of cut. It later went S7 so I do know about the bearings on these. Myford made some spindles especially for me as the one in it was worn which would have made rescraping the bearing cone tougher than need be. I would have probable requested a new cone actually but my Boxford turned up.

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Raglan. Nothing bad to say at all really. Moderate wear on the side of the rails didn't cause any problems at all. I suspect it's down to the width of the bed compared with Myford. It did produce some taper as a result but finish was still good. Mine made an odd noise. The machine tool dealers did point that out and asked if I was sure i wanted it. Lathe fever – turned out that one side of the variable speed pulley was cracked but I did manage to make another on it. However when I used the saddle rack feed to add a key way to the bore the feed gear broke right at the end of the work. Turned out that a couple of teeth had been snapped off in the past and repaired with dowels filed to shape. Some one made a new gear for me.

One shaft was supported oddly, just one bearing on one end. I decided to replace the bearing – dropped and cracked a pulley hence repairing it on the Peatol. I should have left it alone.

I did have the bed strips reground. I found some one who was prepared to clock up the unworn part of the inner edge of each one exactly and then regrind the outer edge. it will only be thou's. When I reassembled using the same location dowels it was perfect. They also reground the bits and pieces that fix to the saddle and run on the rails. I'd still have this lathe but for various reasons wanted to move into the house. Not possible with this one.

The headstock bearings would have been the next job. I'd imagine that they are a standard size but the people who did the rails offered to regrind them for me. They do take steps to remove the inaccuracy that may exist in their universal grinder and often did this job for others.

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Various old dogs intending to do them up. These have had spindles running in cast iron so need real bearings adding.

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Pultra – still sorting it out but I have seen the level of finish these can provide if all is ok. A major problem with them can be belts especially for under drive. They appear to have used one of the L series belts and that size isn't available any more. Mine is also kitted out for 10,000 rpm. I need to knock that back ideally some how. 5k would be plenty and allow the bearings to last a lot longer.

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ML10. well the one I have shows that they can be found in good order. I'd wonder about the ones where the spindle runs in cast iron though. It wont go where I need it to go so at some point will be sold. The main flaw on these is the width of the bed against the length of the saddle. It has to be like this the way they have done it but they can do decent work if the saddle is set up a touch stiff. Long ago I seriously considered a new Speed 10 from Reeves. Crowd of Myford 7 owners in muttering why can't they change the headstock bearings on theirs as easily as they can be changed on the Speed 10. Not that simple really comparing perfect with perfect but as it has turned out the Speed 10 would have probably copped with everything I have made since. There might be a couple of exceptions but nothing springs to mind.

John

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[Jeff DaymanParticipant @jeffdayman43397]

My 1949 South Bend 9" lathe has tumbler reverse for the leadscrew. The way the threads are handed on the lead and crossfeed screws, if you have the tumbler set to move carriage toward chuck when feed is engaged, the crossfeed screw moves the tool away from centre. If you want to face toward centre you have to set the tumbler reversed, which if the carriage feed is used moves tool away from chuck.

Not a huge problem usually, but when facing large items it is a bit of a pain.

Back gear teeth are evidently a bit delicate – several were broken on mine long before I got it. However back gear works fine even on heavy ops with broken teeth and all.

The thrust bearing on the South bend lathes was originally a red fibre washer running against a steel one. Pretty chintzy, but these lathes were not very costly to begin with, aimed at school shops and home workshops. This fibre gizmo started making funny noises a few years ago so I changed it to a needle thrust bearing and heavier ground washers. Cost about $20 from McMaster Carr as I recall. Works fine now and no more "ticka ticka ticka" noises when drilling etc.

Other than these little issues I'm thrilled with this machine, it has taken a beating in its' many lives but still is capable of fine work with minimal fuss. Hole thru spindle is mighty big too, 3/4" if I'm not mistaken. JD

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