Bear in mind that any new machines you see at shows have been 'prepared' so don't necessarily tell you the state of the one that gets delivered to your door...people have sometimes been very disappointed to find how roughly finished they can be and how much work is needed to get them into a decent state. It's also very helpful if you can take someone with you who knows machines and can point things out to you that you won't have thought of.
Greg
Why??
Short of dropping one and breaking the bed the parts that wear out are usually simple ones. Pulleys, belts, leadscrew's and nuts are all easily made, [ except belts which are of the shelf ]
I ran an ML7 for 31 years, the last 10 commercially. In that time I had two sets of pulleys, bought from Myfords. Odd belts, bought. Countershaft and bushes, MS bar and off the shelf oilite's. Two cross slide screws and four ? nuts, again Myford Extended cross slide, made from steel plate Extended top slide, made from steel plate Two motors, shelf stock.
So if this had been a spurious import I would have had to make the pulleys and screws. Not something that would put me off.
Most are belt drive machines so expensive hardened gears don't come into it.
Tim Leech just repaired his CVA selector fork by welding and filing, so don't be put off.
I run two TOS lathes, nice machines but boy are spares pricey. One of the fastest wearing parts is the traveling start stop clutch. This has an internal hexagon broached in and costs a fortune. Just boring it out and loctiting a cut down 26mm socket makes a very good repair for a fiver but how many cough up and buy the genuine article?
-- Regards,
John Stevenson Nottingham, England.
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Careful, not always so. Most of the machines you see on show are old stock, some date back to previous shipments. Dealers prepare one, fit it on a stand, bolt everything that can be stolen down and that's it. that machine then does the shows show in, show out.
Make sure you ask what has altered on the present shipments. Often mills have greater table travels than show models etc
Ask them how old the show machine is.
Another thing is someone commenting on an XYZ machine bought 3 years ago from ABC machine tools isn't always a valid opinion as most companies run a continually updating service as new shipments come in.
I have two heads off X3 mills on my bench at the moment, one early one and one from the last batch into the country. The fit and finish on the last one is light years ahead of the early model.
-- Regards,
John Stevenson Nottingham, England.
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Just pricing a set of bed wipers for a Colchester Triumph 2000 tends to cause severe weakness in the knees...:-(
Tom
I'm sure every part is easily made if you have the facilities to do it, but most model engineers don't have the facilities to make a new lead screw for example, even a nut is not easy if you can't get a tap 'cos they're some odd Chinese thread.
The parts I've had to buy from Machine Mart weren't the sort of things you would try yourself, a compressor con rod and an engine hoist hydraulic ram, if either of those wasn't avvailable I would have scrapped the machine rather than wasting my life trying to make a replacement.
Of course you can pay someone to make any part for you, but I would expect the cost of even something as simple as the cross slide lead screw I needed for my Boxford would make it cheaper to scrap the whole lathe!. Such a simple little piece takes on a whole new challenge when you know it has a drive gear machined as an integral part of it.
Greg
That's the whole point of owning a lathe, they can replicate themselves to an extent. True your con rod and hydraulic ram are other things but I have made both in my time given basic machine tools but as you say cost comes into this.
Your Boxford cross slide screw is a classic example. You use the lathe to make a new screw plus a piece for a tap as well. The new screw is stubbed into the old shaft so you don't have the problem of making a gear.
This also may give you the opportunity to redesign the nut to provide some adjustment for wear.
A new screw is only a screwcutting exercise, nothing more.
If you were unfortunate enough to manage to wear a leadscrew out in your lifetime ?, then generic cut acme screws are available off the shelf from many suppliers. Someone on this board recently went this route by buying a length of screw from Kingston Engineering or Halifax Rack and Screw.
-- Regards,
John Stevenson Nottingham, England.
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Yup, that was me. =A326 for a 30" length of 5/8" L/H Acme rod in EN8 from Kingston Engineering, and the kind loan of Charles Pings lathe and I had a new leadscrew for my ML7. I needed to turn the ends down for the bearing diameters and unfortunately the leadscrew wouldn't fit through the Myford spindle otherwise I would have done it that way.
Peter
Pictures of it here:
Peter
Greg, surely that is exactly what a lathe is, it's one of the facilities that you need to make lathes. As John S has said many times if you have a reasonable lathe (and we are discussing reasonable lathes here) it is merely a thread cutting exercise. I've also seen people replace leadscrews because it is "slightly" bent, if they had seen how they come out of heat treatment during manufacture they would have had a heart attack, bananna comes to mind. They were just straightened, of course modern manufacturing process (even the Chinese one) has negated the need for this. It also doesn't matter if the original bit was hardened etc, these lathes are built to run day after day, year after year, thats what industry demands. A replacement made form a piece of reasonable steel that we can work will last a long, long time in the amatuer workshop. I can not comment on the smaller/cheaper machine mart type lathe but I have been involved with a number of various Taiwanese and Chinese machines and have been lucky never to find a strange Chinese thread. I've found a mix of imperial and metric but nothing that was not available off the shelf. Interestingly I have found a "b******d thread on an Indian piece of equipment but that was easily re-cut.
I have had some problems with spares from Machine Mart but to be honest when a bush failed on my (=A316) angle grinder they just gave me another grinder and told me to keep the old one for spares. It was the work of a few minutes to turn up a new bush and now I have two. To be honest they are taking tools into the "throw away" world, I've just bought one of their engine hoists for the huge sum of =A3150, it works fine and as long as I get a reasonable life from it would not object to having to replace it in a few years anyway. Incidently the jack on mine looks fairly generic and could easily be replaced with another item.
It would if you bought it from Boxford but that's why RDG sell them, depending on which type a maximum of =A360 plus another =A330 for a nut. I haven't looked on E-bay for the typical cost of a secondhand item but I suppose you could beat these prices for a used item. With the proliferation of CNC maching facilities now available it is surprising just how cheap these items can be if someone is prepared to order a reasonable sized batch. It seems to have started a small industry to provide those parts that wear out on the popular machines. Leadscrews, half nuts, change gears and chuck backplates are now available from third party suppliers at what I consider reasonable prices. The problem with relying on "parted out" machines via E-bay is that typically the same parts wear out, a reality that's difficult to spot on the picture of a bright shiney bit on the PC screen.
One other thing that surprises me is that if these import machines are as much crap as we are lead to believe then why isn't there a vast array of spares available from parted out machines? Possibly because they are still being used and are still doing a reasonable job for someone. I won't repeat John's story but I rebuilt a Taiwanese 918 type lathe using generic parts (bearings, gears) a few bushes/shafts turned on a Myford Speed10 and a handfull of nuts and bolts off the shelf, believe me if I can do it anyone can.
Best regards
Keith
Hey Peter that looks an excellent job, what about a small batch and E-bay? Might pay for a few endmills.
Regards
Keith
Yep - my friend George went this way the other week to replace the long feed screw on his mill. I put in the drive keyway on my Bridgeport for him using the horizontal attachment.
Model Engineers always used to be high on the ingenuity count, as limited funds and machinery forced a head scratching approach if objectives were to be achieved. This seems to be dying out and being replaced with a 'buy it made' and 'throw away' culture.
oh heck AND the policemen ARE looking younger !!!!
AWEM
You can't use a worn main lead screw to cut a replacement for itself, the result will be just as inacurate as the original and anyway you can't cut a thread as long as that on the lead screw!
My cross slide lead screw includes a gear, and no I'm not about to bodge the old part with the gear on to a new part as has been suggested because I don't botch!. And anyway it was the gear that had been knackered by the school kids 8-)
Which is where I got mine from, well recomended. Why on earth would I want to either botch it up or spend all the time and money getting set up to cut gears when I can buy a well made part for these prices?.
I realise that some think that keeping old machines working is an end in itself but not me, to me machine tools are just that, tools to make something else. I like to have something to show for my efforts not just be able to say after days of work "the lathe's still working", so I judge every repair job carefully and won't waste silly amounts of what is everyone's most precious resource, time. Would any one here make a bolt that they could buy for 10p ?, well I wouldn't 8-).
Actually I don't think that they are crap as a general rule, though there will inevitably be exceptions, but pretty much everything made these days is poorer than it once was. I've just bought a top of the range Hotpoint washer/dryer and it managed three wshes before the motor went!.
Greg
As a general rule people's disposable income is rocketing and the price of things is plumeting in real terms, it's happening right across the board not just in this hobby. As a result people are less and less inclined to waste their precious spare time, but I agree this leads to less ingenuity. I've been pretty ingenious in my time, as a youth I couldn't afford a lathe so built my own from bar stock using a workshop in the evenings, now I earn enough to buy a new one in a few days so choose to spend my time on other things.
Anyway, each to their own, there's no right or wrong way just different ways 8-)
Greg
A bit of "chicken and egg then" how do you think they made the first leadscrews. Leadscrews rarely wear over their entire lengths and even the most worn I've seen have long sections near the tailstock that are unworn. A bit of thought and inginuity would sort the job. Worn nuts are only really a problem if you don't know how to remove the affects of the backlash. I had thought we were discussing the cross slide leadscrew that is considerably shorter than the main anyway.
The guys that suggested the various repair methods don't "botch" either, actually most botching is done to reduce manufacturing costs and increase profit. More compromises to good design and build are the result of profitability issues than anything else. With regards to it being the gear damaged you didn't mention that so guess my crystal ball has a fault.
As you were the one suggesting that Boxford's could be supported by " a steady stream of parts on E-bay" I thought you might have used your own suggestion. I was merely trying to be helpful if you needed anything when the stream wasn't in full flow.
Either out of interest or financial necessity many who read this information do need to use perfectly valid engineering techniques to repair their machinery. When you do not have to run around earning a living and are doing something that interests you time is rarely wasted, particulary when another skill is mastered. Of course we also need to remember that one mans 10p is another mans fortune.
I though we might have a little common ground here but I cannot agree that "everything" is poorer. Machine tools in particular are one area where our grandfathers would have killed for the levels of accuracy that we can now buy for a few pounds. Sympathise with the washer/dryer though had a similar problem with the same manufacturer myself so buy elsewhere now.
Best regards
Keith
Then you thought wrong I'm afraid, my 81 year old mother needs the simplest possible way to wash clothes without having to drag wet things from one machine to another, to maintain her much prized independence as long as possible. This was the obvious answer with it's fully automatic wash and dry so I bought it for her and will probably buy her another brand of the same if I can find one.
To be fair to Hotpoint they are taking it back for a full refund with no grief as they seemed quite embarassed.
Greg
We had a 'cheap' Hoover washer/drier which did thousands of nappy washes etc when the kids were small and lasted a good number of years' hard work. Gave it away still working & got a relatively expensive Zanussi which lasted about 18 months before completely self-destructing, beyond economical repair. The drier bit was just for 'emergencies', rarely used, we don't have space for two machines. Gave up after the Zanussi, got a simple washer after that.
Cheers Tim
Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service
Hotpoint are actually a pretty good company regarding service, and are one of the few that honour the little known 6-year consumer warranty as laid down by the sale of goods act. Call them anytime in that period for a breakdown on one of their appliances and you pay a flat rate call out fee of about =A360 to fix any problem - however major - including all parts and labour. I had to replace our 19yr old Hotpoint washer/dryer last year, not because it broke but 'cos the Mrs was getting jealous of me buying new toys and wanted some new stuff herself .
Peter
Thanks Keith. Only trouble with doing that is that I'd have to borrow a lathe every time as the 5/8" leadscrew won't go through the damned Myford 17/32" spindle bore:)
Peter
Peter, yes they're a problem those Myfords (Bg). On second thoughts I suppose Charles's commercial hire rates would knock the profitability as well. Anyway, thanks for posting the details it's certainly one I will put in the memory banks as I start to re-build this gigantic Bridgeport. It seems to be growing daily, I don't know what John fed it on but it was obviously good stuff.
Best regards
Keith
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