Member postings for Ajohnw

It all depends on the use it has had Carl what ever make of lathe. As to Warco which range of lathes? To get near Harrison etc it would have to be from this range. Maybe some loose screws needed tightening

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At least the gears on these are hardened and ground. I have had the gears in the cheaper range. They aren't up to industrial use and some seem to have gone plastic to kill noise. That aspect is disgusting on machines I have heard. Even worse that correctly adjusted change wheels. Frankly if I was buying I'd rather they did pure belt drive. There is always the question of how well ground though. I'm reminded of a hand scraped tail stock. It was but that doesn't mean it was aligned.

Then to be fair some one would need to do a price comparison with the same off say Colchester but even a Boxford is 10k plus. I am assuming some are cheaper than their high spec one.

The other point is I very much doubt if a truly decent Harrison of the size mentioned could be found for under £3k or even more especially with the kit that is needed is with them. Then comes the question does it have a hardened bed. That all on it's own can make a huge difference to wear rates. That's why I mentioned a Boxford VSL, it will be.

There was another ilk of Chinese industrial machines coming over some years ago. I saw some at Excel. They were selling a lot of them round Coventry. Much more traditional looking, big head stock and also advertised as precision. I ask how much precision and was told that there was something in them to take care of spindle alignment. They sounded right, looked right but way too big and heavy for me as small as some were. Then there was cost. There was even a 1in bore spindle all belt driven one with a reasonable speed range about elsewhere too. Not for long though.

John

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Edited By John W1 on 07/07/2015 15:19:19

Not looked for years Phil but my recollection is that nuts and bolt in BS form are sized to give little but some clearance on the crests and valleys. The die heads I have used do provide the correct form but yes the flanks do the work so an accurately pointed tool cut thread will be as good except for weakening the core of the male part. That often doesn't matter on the female part.

Yes my soul was sold to Lucas for my indentures and I was paid so little even bus fairs were a major expense. I never left really but was sold on to other companies 3 times.

John

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Edited By John W1 on 06/07/2015 23:46:11

Actually a lightly to zero wear ML7 is a pretty rare beast. I would be inclined to sell it all together as well especially if ebay is involved even with measuring stuff etc.

A lot depends on how much work it has actually done really and only you can judge that but a few small steam engines and few odd bits and bobs would suggest it aught to be like new if it's been looked after. One very telling things on an ML7 is if there are any shims left under the bearing caps. Looks like there is but can't really be sure from the photo. They are terrible things - laminated. The general idea is that when the bearing show wear a layer is peeled off and then the bearings should be scraped to fit the spindle and keep it level with the bed to very fine limits. Great fun as the front and rear have to be worked together. With luck only the top ones have to be done. I did this with the phos bronze bearings Myford switched to. The first batch that had an insane scraping allowance on them, way more than it should be and both top and bottom had to be done. The shims Myford used are a pain because it's rather difficult to peel a single layer off.

Not sure what the X-Y stage shown in the last photo is for. Interesting way of making one. I'd guess it moves the round part around so might be used to centralise something or the other with rather limited travel.

If not worn at all it is easily worth the higher number mentioned subject to the fact that all even new lathes vary a bit. Getting that might prove difficult though. One simple way of testing the headstock bearings is to free the spindle from the belt and rotate by hand. There should be a bit of drag. As I understand it not much just a little. The Myford manuals may give a clue on that but it's the sort of thing that may vary out of the factory.

John

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Edited By John W1 on 06/07/2015 23:33:22

I feel I have to say something about buying something like a used Harrison. The lathe on the ship might have been brand new or scarcely used when it was fitted. I doubt if a lathe on a ship is used for long periods daily either. It's probably well maintained as well. Reminds me of a conversation directly with Myford who couldn't understand why there are so many of their really well worn machines about as they have them 30 odd years old in use and still fine. They know how badly they can wear as they get some back for reconditioning.

Basically the older a traditional make of lathe is the more likely it is that it's seen extensive use at some point in it's life and one persons view of a lathe in working order may not match others. Take true toolrooms for instance. They have grinders of all sorts about and a lot of work finishes up being hardened and ground so taper and finish on work that comes of the lathe doesn't really matter. It will at some point for some sorts of jobs so out goes the lathe and it's replaced.

Past something like the 50's or 60's I don't think which main make matters that much. There are some rolls royce brands but even a rolls royce wont run well with loose big ends, worn out steering gear and a burnt out valve or two. One of the worst catches with 2nd hand machines is makes like Schaublin. One that still deserves the name is likely to cost a lot of money also even if it doesn't any more. DSG is another also Lang but both of those are likely to be a lot bigger than the Schaublin and ideally need a machine shop floor. A bit thicker than a typical garage.

I'm time served too.

i feel some could buy a used main brand and finish up with something worse than a lower end Chines lathe - very easily if they can't test it properly before they buy. But an excellent example of one of the main makes is a better option if available and people are ;prepared to pay the price.. Sadly some dealers will be perfectly happy to sell machines which are past it really. On the other hand how bad a machine can be before it's a problem depends on what is going to be done with it.

John

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Maybe another warning in used 3 phase machines would be worth mentioning. Lathes generally have all sorts of interlocks fitted on them. When driven via an inverter these usually have to be junked as nothing should be between the inverter and the motor. Some people have "fun" sorting this out. Often for home use people make no use of them at all other than a prominent stop button added by themselves. Business type people who might get health and safety visits do not have such a simple life.

Noticing metric / imperial mention. Depends what the bikes you wish to work on use. If metric maybe a metric lathe would be a decent idea. Metric Boxfords should come with a type of screw cutting indicator that allows most pitches to be cut without reversing the lathe etc. Not sure what the Chinese metric lathes have on them. Metric on imperially lathes need conversion gears. People usually insist on having a 100 / 127 compound gear to do this with and the lathes have to be reversed but close approximations are generally more than adequate. Lots of screw cutting in practice is done with taps and dies as it's quicker anyway.

John

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Some one was asking a similar question on another forum with similar limited experience. It's a tough one to answer as used lathe buying can be a mine field so in the end I had to suggest new cheaper Chinese. He was thinking about biding on a well used Myford ML7. The Chinese industrial machines are in an entirely different budget bracket. The comment they make about the cheaper ones and industrial use really relates to how long they will last in some respects if worked hard for long periods but there are other factors as well such as chuck size.

One example of the used lathe nightmare. Some one on Ebay had the bright idea of posting a video on a Colchester Triumph including showing it working. I've used numerous geared head lathes and know from the noises it was making that it's seen rather a lot of use. Also from the way the swarf was coming off that the headstock bearings are very probably rather loose. That can be a very expensive thing to fix if needed and some wont be adjustable. Given the state of the gears there will also probably be a lot of bed wear. Net effect, lathe turns a taper what ever you do and also the finish is likely to be poor unless heavy cuts are always taken. The cross slide will also very likely be rather worn as well. It's possible to buy completely reconditioned lathes of this sort of ilk from dealers but costs rise.

Spindle bore comes down to turning bar stock really. If the bar wont fit through the spindle pieces have to be sawn off and need some length left to hold in the chuck. When the actual part is parted off a short piece of bar will be left over. They build up as often they are too small to be of any use. A pro view on that for a SMALL lathe would be a spindle that can take 1in bar as that would cover a lot of work a lathe is likely to do. It can be handy to have a chuck on the lathe that has a 1in or more bore as that means that the left over bits can be longer and are more likely to be of use.

Lathes generally specify swing over the bed - often the cross slide travel wont cover that range. I'd hope it always covers the swing over the saddle and some as clearance is needed.

Some one mentioned a used Boxford. My personal feeling is that these are likely to be a better buy than many other used lathes but they are all under drive unless an ME10 can be found which is a bench lathe. The newer ones could also be bench mounted - cost used with some kit probably £3K plus for a fair example There will be well worn examples about of all types though. On this range a bigger spindle bore means a VSL which has 35mm bore. Those are far more likely to have been used in work shops that turn from time to time so should be a good proposition. The costs of chucks escalates on these though due to the spindle fitting as it does on many other lathes that don't use a simple screw spindle fitting. The older Boxfords may come from schools etc - or may have been used heavily by some home turner until it wont meet their finish/accuracy needs or some job turns up that needs a bigger lathe.

If you do buy used do hang on until one comes with the basic bits and pieces - 3 jaw, 4 jaw, face plate and at least the fixed steady. Burnherd chucks too or at least one of the well known makes. To be honest though Burnherd chucks are still better than these which is why they cost rather a lot more. Better in this case means less likely to break in use. It's not too difficult to strip or bend the scrolls in some makes of 3 jaw chuck just by tightening them too much. It's a bit harder to do that on a Burnherd.

John

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Edited By John W1 on 06/07/2015 12:01:47

i tried to find a picture of the part out of curiosity. The only brass blanking plug I could find fits on the steering axle assembly. Image here that even shows what appears to be poor workmanship - blunt tools probably

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I don't want a flame war either but I can assure you that die heads can produce very accurate threads especially compared with modern usual standard nuts and bolts. Or even compared with modern precision stuff such as high tensile cap head screw etc. It would be interesting to know how they did make them. It looks to me like a part designed before design was more closely tied up with ease of manufacture and some parts were even machined by hand. It might even be a tapered thread on the original but it looks like it tightens down on a bush so no need.

I worked for Lucas who owned Girling and had no idea that they were once into suspension parts - king pins by the look of it. I also spent a short time in an auto shop setting during training. They generally use methods where the accuracy of the basic lathe like machines hardly matters so that high accuracy parts can be produced easily

Oh - if you hacksaw the slot obvious but some might not know the width can be set by fitting more than one blade. Also cleaned up with a needle file more easily then if some one is thinking of entering certain types of show competitions..

John

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Edited By John W1 on 06/07/2015 10:30:14

I use these people for none ferrous as they are local. They don't show what you want as stock but it might be worth asking. Good / bad prices? No idea as I usually want cut to size and can just go and get what I want.

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Also these people

http://www.rapidmetals.co.uk/

John

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Edited By John W1 on 05/07/2015 23:34:48

LOL not too good a post really as I stopped from time to time. It's easy to loose the plot then.

Some of it relates to cutting internal threads - mention of a DTI to show when the end of the cut is reached. Also running backwards but that may be of use in other situations. If a chuck unscrews = mess, a big one.

One other thing as well. Say it was a cap. It might be better to screw cut a length of tube and then make a top for it and loctite it in place or even use solder paste if it's brass. When something is difficult to machine fabricating it cab often help.

John

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If you want something that looks exactly like the original part there are several ways of going about it. Using a single point screw cutting tool wont achieve this as the general idea is that the bar is turned to a size under the normal thread dia that removes the need for the rad on the crest of the top of just about every imperial thread form. As it's a pointed tool it needs to cut deeper than the correct form as well. You should be able to find calculations for this about on the web. The information needed is available when the full details of the thread are given, crest and root rads etc..

I've ignored that you mentioned the word cap so if it is the above needs reversing.

If you have a feeling it's a cycle thread it's probably a brass thread, whit form rather than 60 degrees. Brass is usually reckoned to be 26 tpi but I have a feeling 32 is used as well. At all diameters. The idea is not to weaken tube wall too much as say using 10 tpi which might be more sensible at some diameter. Thread gauges should come in whit and unified as then it's possible to see what the thread angle that is being copied is. Often now they only come in metric and unified so if the flank angle looks to be wrong using the unified guages it's assumed to be a 55 degree whit form.

Screw cutting with a chaser isn't really any different to cutting with a single pointed tool other than when the end of the thread has been cut the chaser has to be wound out of contact otherwise it will mess up the thread. A single point tool can be left in contact as it will just turn a groove at the end of the thread. In that case screw cutting just has to be disengaged. With a chaser the tool has to be wound out of contact and screw cutting disengaged at the "same time"- very slightly later. Not that difficult to do with the lathe running slowly providing that there is a bit of space available at the end of the thread for the tool to run on a bit. A typical chaser may need modifying on an off hand grinder. Some may have a bit of a lead in. That needs grinding off slowly without over heating the chaser and wrecking it's temper. If it is a cap it wouldn't be a bad idea to cut a recess at the end of the thread to provide some space for either type of tool to run into. Sometimes when a single point tool is being used the noises change when the tool enters the recess. Some fit a long travel DTI to the lathe bed for tricky jobs and use that to gauge when the end of the thread is reached.

Not often mentioned but for internal threads and a single point tool there is another technique. Run the lathe backwards with the tool upside down or even cutting on the opposite face to the one usually cut. This way the tool runs out of the work rather than in. Problems - screw on chucks might unscrew and normally screw cutting is engaged some distance from the work so that when the actual cut starts all play has been removed. Might work out with a decent sized recess. With a chaser too if it can fit into the recess. It would be best to only have a few teeth on it, only 2 are needed really for machine chasing.

Once upon a time many threads were cut by hand with chasers. They can also be used to correct single point cut threads to the correct form or correct the pitch slightly when some one has an imperial lathe and wants metric. Chasers self correct as they cut which is why hand chasers have so many teeth on them. The modern machine chaser is in the form of a disposable carbide tip. Advice from a now rather old clock restorer is to make up a handle around 18in long for fully cutting threads with them from scratch. What I found is that it's best to lightly score the work with the chaser stationary 1st and the use this as a guide to feeding the chaser along by hand. Higher speeds for finer threads seems to work best as it's easier to match the required feed speed.

My boxford came with it's hand turning rest - make me think it must have been a model engineer that initially bought it.

John

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I think those weird shaped nuts are an English thing. However I dont think that it is one of these

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Nice nuts - can put a crow bar through them to do some English heavy duty turning. I'd guess the slide rest - the name of the cross and compound, is I suspect continental or at least doesn't belong with the lathe. Hence the couple of questions I asked.

John

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My understanding is that Warco do the tests not the manufacturer. Those figure look pretty good really and I would hope that they are always generally within limits.

Me - if done in the factory or what ever and they didn't seem to be correct - send it back, supplier to pay return costs.

Actual turning is the final test on any lathe. In real terms that is the one that counts but some reassurance via a dti does indicate what the lathe is likely to do. Then it's a case of the user making sure that they always take play out of the lead screws when setting cuts and and also to set sensible amounts of drag on the gibs. That can be important on some lathes even rather large ones.

Personally if any doubt I do feel that it's worth the minimal amount of effort needed to make a between centres test bar and or just to do a few very simple turning tests.

John

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There are 2 sides to every coin. Maybe the alternative to buying a "casting kit" is to buy a used lathe. The problem with used lathes is that wear can produce similar accuracy problems though if the lathe was well made the they will largely relate to the headstock spindle and the bed with a fair chance when this has happened that the slides wont adjust correctly as well.

Costs of thing like lathes can be more complicated than they may appear. If cnc machines are used then they don't come for free and time on them has to be paid for. It's very expensive time too due to the cost of the machine. Lathes have their problems as well. The usual answer to obtaining stable castings is to leave them lying around for a couple of years, preferably outside as the rust will help break down the tough skin they tend to have easing machining.I suspect the castings need to be allowed to cool very slowly too and might even receive some heat treatment to help.

I'd love to see a copy of a warco test report on this level of lathe - can some one post a legible photo of one.

John

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I forgot to add vat to the used price which when they can be found usually has to be added. I would have thought 15K was a bit high though or is it the TS version? The TS was designed and made to meet the most stringent specifications available. The Industry version more normal standards. I think they only do what is intended to be a training / school lathe now. Not sure.

I wonder at times but when I look at the bits and pieces I have with my ME10 the on cost over the basic lathe would really hurt even on a used one if it came with no bits. An old rule of thumb was that equipping a lathe may work out more than the cost of the lathe itself.

John

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You would be talking a lot more than 4 times the price.

This is a test pass off of a cheaper lathe Boxford made some time ago now. Just borrowed of the web.

They still make a lathe, maybe the super accurate tool room version as well. Price for these sort of numbers now - I believe it's over £3000 for a reasonable used example. New price not sure but could be 3 times that,

The tests shown on this sheet don't show where errors are - only the accumulation effect of them. They also tell users to correct errors down from this via bed strain using tests which involve actually turning.

On the other hand maybe they don't make light duty lathes that well as they might on purpose. On the other hand errors should reduce with size -. it's also possible to buy a new Schaublin of course.

John

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Edited By John W1 on 03/07/2015 17:51:31

The books are worth a read as there are some interesting thought processes. Just as a for instance attaching things to the spindle of his dividing head. People might be inclined to think it must be a morse taper but he uses a long parallel bore instead as it's more suitable for model engineering use. it is too. No need to make or buy morse taper adapters and very easy to make something to attach what ever.

On the other hand the complications he adds to his set of rolls bamboozled me - there are easier ways or making those. Too much reading of books like these can also prevent people from thinking themselves.

Some time ago I owned a slightly scaled up version of the UPT. Entirely fabricated and not from plans. Really all that is needed is a picture. Scaled up it can offer a bit more in the drilling area also for reaming dead square as well leading to much closer tolerance holes.

John

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The important aspect of a tailstock is the behaviour of a centre in it. Any test based on it's od assumes it's concentric which it may or may not be. Hence the need for a between centre test bar with varying projections of the tailstock quill.

I may have mentioned lapping with a mix of CIF kitchen cream and oil. This will not correct errors only improve smoothness and for perfection needs a bit of thought to make sure that the added smoothness is applied evenly along what ever slide it is.

John

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It's about on Ebay as well in a couple of forms. Seems the one from the link already posted is friction braising - the brush and the end of the rod is dislodging the oxide layer. See ebay 280619538986.

There are also some fluxed rods on there which I suspect would be better for butt joining tube etc.

John

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Aircraft have been held together with epoxy but they also tend to use rivets because the peel strength isn't too good.

You might do better to find a cheaper source of something like this

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I've never tried it but solders for aluminium have been around for some time.

John

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Best click on the images on the style I linked to. It can also be fitted via a clamp that comes with it or screwed to something as the original image shows.

John

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