Lathe change

In order of likelyhood:-

Boxford AUD Colchester Student Colchester Bantam Super 7B with cross feed Conny Sewer Hardinge HLV(-H if you can get it))

Probably lots of others.

Whatever comes up on fleabay/goindustry/etc that looks to be acceptable

Regards Mark Rand RTFM

I'm very happy with my Emco Maximat V10, which replaced a Super 7. Little bit larger, longer bed - and a simple mill attachment.

Regards,

On or around Thu, 04 Sep 2008 23:46:53 +0100, Mark Rand enlightened us thusly:

Harrison L5?

Colchester Chipmaster, if you can find a good'un, especially if the variator works. In fact, unless it's been rebuilt with a variable speed motor, it's essential that the variator works. very nice little lathe though, if in working order.

The student is a bit big, compared with a Myford.

They are *all* a bit big compared with a Myford. A Myford will fit comfortably on a tabletop - the rest won't.

-- Peter Fairbrother

On 4 Sep, 22:54, "Bill" wrote:

Bill, a few clues as to what is important to you might help the suggestions i.e. budget, room available, equipment you need with it any particular function it must do etc.

If room is limited and you just want a little more machine then I agree with Mark's Boxford AUD suggestion, much heavier build than the ML7, gearbox and power feeds to saddle and cross slide. My long bed version takes up about 53" x 23" on the stand with the standard version being about 8" shorter. The AUD (4.5") would also be a strong suggestion if budget is a factor as they are about the best value for money available for smaller but still very capable machines. Beware though there are some rough ones about as well as some that will not have had much use at all. If budget is less of an issue then the Myford S7 with PCF is a very nice machine and I have not felt particularly limited in the rate that mine will remove metal. If size is not a problem and if you are happy with an older machine then the other suggestions from Mark and Austin all come into play. I personally would be a little careful with a Chipmaster as although it is a fine lathe the variable drive system can be extremely noisy when worn so budget for a VFD to overcome that. I also would not argue with Stephen's Maximat V10 which is a nice lathe if you can find a good one. A difficult lathe to buy second hand though as either, if you are very lucky, people don't realize how good they can be and they are dirt cheap or they DO know and they want a fortune for them. I guess I would also have to say that if poorly equipped they can be expensive and while a lot of the smaller Emco range appears a bit lightweight the V10 is where they start to get serious but still much lighter built than the Colchester etc. Excellent build quality for the original ones though. If you like "bright and shiny" and can put up with Chinese then something like the Warco BH600 is still excellent value at the moment.

Regards

Keith

On or around Fri, 05 Sep 2008 11:26:07 +0100, Peter Fairbrother enlightened us thusly:

then again, most come with a nice solid stand, which is good.

The boxfords, unless they're UD models, aren't necessarily on stands.

I guess you could unbolt the student from it's stand/cabinet and put it on a table, if you had a strong enough table.

The chipmaster is only 3x20, but it's well solid.

I think you made a typo there, as I'm sure it's 5.75" x 20", same as the Bantam.

Peter

My sense of proportion might by slightly skewed by the fact that I migrated from my short bed ML7 to ex-father's long bed 7B (that he claimed to have bought for my 9th birthday :).

Having fitted it to a stand, the other lathes _are_ bigger than it. But not necessarily vastly so.

Case in point. The long bed ML7B is 24"x55" on its stand, the Hardinge HLV is

8" longer and 5" deeper. The reason for suggesting the "upgrade" is that the Myford weight in at 5cwt and the HLV tips the scales at half a long ton. Similarly with other "small industrial" lathes. That weight difference can make a big difference to the amount of swarf that you can produce in an evening.

If one were really stuck on the concept of small enough to live on the table, then a gearbox and power crossfeed would be gilding the lily and wouldn't fit the last desire to take bigger cuts.

Mark Rand RTFM

Nyah nyah nyah - of course I want a HLV-H, and I'd make room for one at a shot, but I can't afford more than a grand or so - which is unlikely. How many do you have now?

sad and jealous :)

BTW, do you still have any of that 95 mm dia black EN24T left? Can I buy

150 mm from you?

Yuss.

-- Peter Fairbrother

It's only an HLV and it cost me about £250 (plus two years so far rebuilding it without seeing it run yet...)

Still got some, but it's not EN24T, just EN24 i.e. Black and annealed. Doesn't machine as nicely as the heat treated EN24T, but doesn't affect the final result if it needs heat treating afterwards.

I'll get a length in the post for Monday if you want.

Mark Rand RTFM

On or around Fri, 05 Sep 2008 15:13:37 +0100, Peter Neill enlightened us thusly:

yeah. 5x20. it says so on the machine, chances are it'll go a tad over 5.

for example, although I'd be a bit wary of a noisy variator, although the advice give in the excellent lathes.co.uk is a touch contradictory on this point

- untoward noises are bad but they are "rarely silent".

He goes on to suggest that they mostly end up being converted to electronic, and further describes someone who over-rated one to run at 4000 rpm.

On or around Sat, 06 Sep 2008 01:16:35 +0100, Peter Fairbrother enlightened us thusly:

Ebay item:

330268377847

Student 1800, BiN at 990. Looks good.

Aisde from being well made the Chipmaster has a good reduction from a back gear so a modern VFD works OK when the variator gives up. I've known it be done and work well although how good it'll be at 100rpm big cuts is open to debate - but if you're used to a Myford then it's a hypothetical worry

Charles

Snipped Interesting Stuff

Mark, in reading your comment here I thought it must be at least 4 or

5 months since our last update on Dovetail grinding etc as related to "just an HLV". Have you made progress or indeed finished the bed re- build? Apologies if I have missed an update but family diversions make my forum access irregular at the moment. I am always on the lookout for such a machine (at a similar price :-)) but even if I fell over one at the moment I would lack the confidence that it can be "sorted" without spending something a fortune.

Regards

Keith (interested but impoverished of Wales)

Keith

One of the big benefits of a Hardinge is that the bed ways are removable and therefore easily taken off for regrinding. The fact that Mark chose to do it the hard way with an undersize surface grinder shouldn't put you off!

Charles

Thanks Charles, I had forgotten that Mark chose the "advanced route" for his rebuild. I think that there was an issue with regard to the alignment of the dovetails being different from the alignment of bed location dowels so I was interested in how the bed once removed was aligned for grinding the dovetails given that they were obviously worn and wouldn't provide a datum. The problem I have is there are few local grinders with a machine large enough who will "fiddle about with these one off jobs" and even if they do they will only do exactly as they are told with no guarantee of accuracy, except for parallelism.

Not that I have found a suitable machine candidate yet you understand, but I have (clears throat), found an HLV in the corner of a workshop that looks very unloved and "well worn" - at least that was what I told the guy who runs the place. :-) He just happened to mention that they could well be moving early in the New Year and was moaning that the scrap price might not hold up long enough for them to get anything for it once they are able to get it out. I did say that I might well be able to pay a bit more than that and clear it for free when the two bloody great CNCs that currently lock it in are moved. I will have to keep tabs on the place but don't at the moment want to appear too interested and haven't even looked close enough to see exactly which model it is. No, for anyone wondering, I can=92t seem to remember exactly where the place is :-)

Regards

Keith

It's actually 6 months almost to the day since I started the bed regrind. I did the thickness and needed to take 6 thou off before I got below the wear marks. Once I'd done that I could measure the wear on the dovetails. One interesting thing that I discovered in so doing, was that the bed was not made parallel to the piece of metal it started off as. There are non-wearing vertical edges for the top 1/8" or so of the dovetails. The original plan had been to use these as references when regrinding the dovetails. Unfortunately, Messrs Hardinge put a 12 thou sideways slope on the dovetails with respect to these verticals :-(.

I intend to regrind these vertical bits so that they are parallel to where the bed should be. I can get this alignment from the unworn parts of the dovetails at the very ends of the bed. The reason for correcting this original sloppiness is so that I can use a fence on the sine vice to align the bed.

To align the bed to grind the verticals, I intend to accurately mount four datum blocks on the bottom of the bed and adjust them on the surface table until they're parallel to the correct line. Then I can mount the bed on the vertical sine vice on the grinder and adjust the alignment with a dial gauge against the datum blocks. Once I've ground one side, the other vertical edge side and the dovetails can be referenced from the ground-in-place fence of the sine vice.

It should be noted that AFAICT, Hardinge never intended the beds to be reground. You're supposed to simply buy a new two piece bed and bolt it on.

A minor issue is the fact that I don't actually have a sine vice. I'm in the process of making one based on a 6"x12" electromagnetic chuck that I have.

Unfortunately, pressures of work, spending weekends and holidays trying to find the garden and stuff meant that I haven't yet finished the sine vice.

The recent deluges handily stopped all garden reclamation work for the year :-)

Then to add insult to injury, I got distracted by making an electrically heated salt bath to harden the apron gearbox gears. I spent a weekend hardening them. More time fitting them, toolpost grinding journals, grinding the width of some of them, finding that I hadn't allowed enough clearance for most of them, trimming some and re-making two (too hard to recut). Then discovering that Hardinge had originally bored some of the holes 3 thou too small for the needle roller bearings they were using (explained the undersize, shagged shaft though!) and so on.

Note to self:- Next time fit dowels in the gearbox bearing holes and accurately measure the centre distances instead of making assumptions. Also don't trust that any hole was originally the right size, even if there is a bearing pressed into it :-(

I've got one more gear to finish trimming to get the running clearance to a level that I'm happy with. Then after grinding the clutch bearing thrust races to fit and making new brush caps for the motor and cleaning that up, I'll be able to finally put the apron gearbox on the finished pile. Then I'll get back to the bed.

There is progress, but it's not always in the right direction or speed. I really want to get the job finished so that I can get on to rebuilding the mill, which I was about to start before the HLV turned up!

_ Mark Rand RTFM

Mark

Thank you very much for taking the time to provide such a comprehensive insight to your rebuild, it has been extremely helpful to me. You have also covered some areas where I had concerns caused by stories I heard (20+ years ago) from the technicians that looked after such machines. Their belief, not just with HLV, was that while superbly engineered there was in fact a lot of "individual" fitting with each of these toolroom machines. They also had stories of a number of well engineered "fixes" that were obviously used to recover minor production errors. I have also encountered the undersize bearing housing in aerospace components, mainly to overcome the possibility of differential expansion but, on one occasion" the rep said that it allowed the use of cheaper "standard size" bearings and ground shafting. Apparently, if anything shafting would be slightly undersize, never oversize, with thin housing bearings the other way round; therefore a "small degree" of pre-load would always ensure a zero clearance bearing. In that instance it was not a problem as it was a very short life component. I can't see yours being for the same reason as I wouldn't think the production numbers were high enough. This was over 20 years ago and I suspect production tolerances of even basic items is much better nowadays.

I must say that my confidence is not improved as your bed problems seem only a part of the issue. Perhaps I won't rush at a machine until I can have a good look at it, even if cheap. I suspect like you, once I owned it I would "have" to put it right no matter how long it took. I should really continue to use my present machines until I can out perform them rather than, as it is now, the other way round. Anyway thanks again Mark, best of luck in your rebuild - it will be all worthwhile in the end.

Best regards

Keith