# Lathe bed regrinding



## rockets (Sep 23, 2017)

Hello,

This is my first post in a long time, you know...life..

Having just moved house and having to build a new shed, I've decided to give my Emcomat 7 a bit of a going over (it literally was bought, chucked in the old shed and put to work as I had work for it).

It has a little bit of wear on the shears so I think after 50 years it deserves a little TLC. So far, Brian Caddy at Slideway Services in Nuneaton, Coventry seems to be the best recommendation. Having spoken to him he is very confident about taking any wear out and refitting the saddle and lead-screw.

Has anyone used him? I'm between Oxford and Reading UK, any other recommendations gratefully received.

Stories, points to be aware of and general banter always welcome!

Cheers,
Rockets.


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## goldstar31 (Sep 23, 2017)

I have no knowledge or experience of this service but assuming that it is as good as Blue Diamond at Shildon, County Durham, there should be no bother. That is where my Myford Super7B bed and saddle were done. I did the rest!.

Earlier and on different flat bed lathes, I had the beds 'Blancharded' for considerably less outlay and I did either a considerable amount of surface grinding and or hand scraping.

If the subject is explored in the light of today, and not the days of Edward Connelly, I would mention that materials and techniques have vastly improved- and simplified.

Probably the topic of restoring basket cases which have so predominated and so regularly repeated can be put to bed once and for all. 

I therefore look forward to your account of how professionals do things-- for a change:hDe:

Norm


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## rockets (Sep 23, 2017)

Norm,

I'll keep you posted. The guy gets a good write up on other forums with several Myford owners saying good things.

The Emcomat machine is a similar size, built in metric dimensions being Austrian.

Cheers,

Rockets


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## Wizard69 (Sep 25, 2017)

If you get the bed ground you probably could save some money by re-marrying the saddle yourself.   Generally if the business has a way grinder he should be able to do a credible job.   Way grinders aren't cheap so if he has stayed in business for any length of time I would imagine he does a decent job.

I suspect you will get a bit of sticker shock though.   At least around here it is pretty hard to justify a grind on a small lathe if you have to pay shop rates.

Dave



rockets said:


> Hello,
> 
> This is my first post in a long time, you know...life..
> 
> ...


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## JCSteam (Sep 26, 2017)

Just for reference I was quoted £850 for a bed 're grind, 're fit of the saddle, compound and top slide. This was for a Myford ML4 7x24" lathe, this doesn't include if any parts would have to be remade or replaced. Considering my lathe was bought for £350, with tooling, chucks ect. I simply cannot justify the expense. As it's more than what the lathe would be worth after the work was done, by more than double, triple even! I have been seeking advice on scraping, which is most likely the route I'll go down. For now I've set the lathe up as best I can and I'll see if I can get somewhere close. I have already managed to get the lathe levelled to turn concentric within 1 thou over 3", so 64thou taper over the length of the bed. To put it another way 1.6mm over the length of 600mm. Well out in precision engineering, but for what I am wanting to do may be just fine.


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## bazmak (Sep 26, 2017)

1 thou per 3" is 8 thou over 24" and you cant turn over 600mm lg,probably 12' max so that is 4 thou which is not bad for a new chinese lathe.Be happy with that but keep an eye on it.Have you checked the height of headstock and tailstock.With a piece of round bar between centres check the carriage travel
Also face off a large dia and check cross slide travel square to bed etc As you say if you want to spend serious money buy a different lathe


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## JCSteam (Sep 27, 2017)

Thanks Baz, must have been sleepy when I wrote that
I've measured my ML4 and it's 20" between centers 3.5" center height. I'll put a straight piece of metal between centers and see wether it wobbles much. When I brought two centers together on the lathe it looks as though it seemed level, though I'm not sure what it'll be like over a longer distance.

Jon


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## rockets (Sep 27, 2017)

Some valid points and interesting experiences. I'm yet to strip the Emcomat down so I'll be having a good measure of the bed and looking for obvious other culprits. I'll get a firm quote before I entrust the machine to the grinding shop. He has the facilities to grind up to 9' in length at his workshop. If the quote is more than the machine is worth then I'll live with it until I upgrade.

As JC mentioned, good set up and reworking the saddle might well improve matters considerably.

Rockets


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## Wizard69 (Sep 27, 2017)

It is an expensive proposition to have a job shop grind and fit.    If at all possible consider having the ways ground and then do the fitting yourself.  That means hand scraping the saddle to fit the newly ground ways.   

As for an Emcomat, this is a better quality lathe so spending a lot of money on it isn't a bad thing.   You need to look at it considering how long you expect to keep the lathe.   If it is over 20 years the cost of the grinding is trivial.  I'd be willing to pay anywhere form 1/3 to 1/2 the lates replacement costs if it is a keeper.




rockets said:


> Some valid points and interesting experiences. I'm yet to strip the Emcomat down so I'll be having a good measure of the bed and looking for obvious other culprits. I'll get a firm quote before I entrust the machine to the grinding shop. He has the facilities to grind up to 9' in length at his workshop. If the quote is more than the machine is worth then I'll live with it until I upgrade.
> 
> As JC mentioned, good set up and reworking the saddle might well improve matters considerably.
> 
> Rockets


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## goldstar31 (Sep 27, 2017)

Wizard69 said:


> It is an expensive proposition to have a job shop grind and fit. If at all possible consider having the ways ground and then do the fitting yourself. That means hand scraping the saddle to fit the newly ground ways.


 
Actually, today's answer is to build up the underneath of the saddle with something like Turcite.

I've used Loctite 660 on a No1 Shear on a Myford with success and there are other products like Devcon and Moglice which are used professionally.

Hope this helps

Norm


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## Blogwitch (Sep 28, 2017)

Jon,

It seems like your measurements are way out. going by yours, the saddle and tailstock would jam up solid if you tried to move them at most a 1/4 of the lathe bed length.

There are also a few ways that you can get a taper when turning, and bed wear is the least probable one.

If your machine has the removable headstock, like mine was, then the position of the headstock front to back and side to side in relationship with the bed can easily give very excessive tapered turning.

With regards to getting your bed reground, don't even consider it. The cost of it will not add one penny to the value of your machine, and I can see later, in a year or so, you will be looking for a larger machine, so keep the costs if at all possible down to zero.

Anyone with a good strong milling machine should be able to (with a couple of hours setup) skim across your bed with a flycutter, giving you surfaces that are plenty good enough for the type of machining you will be doing.. The same goes for the saddle and cross/top slide as well. In fact, you might find, if it is the head causing the tapered turning, the bed might be plenty good enough for what you want to do.Just keep it well lubricated with the correct grade of oil, ISO 68.

John


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## JCSteam (Sep 28, 2017)

Hi John, 

Yes it's got the removable headstock, I think I'll need to buy a test bar, or the very least get a magnetic base and dial indicator, mount it to the headstock and dial in a 1" test bar to in the four jaw, then proceed to see if the bar runs parralel to the bed, by measuring chuck end and far end of the bar, with the dial indicator mounted to the saddle. 

My theory is the spindle is fixed so if I can dial the bar in parralel to the head stock (and spindle) then I can use that as a reference to dial in it's position relative to the bed. What would be really handy for setup is a double ended MT1 taper bar, as this would help align the tail stock too. Whilst also useful to align the headstock. Which if I can get to 1 thou taper over 3" i dont think os too bad for now. 

Then comes measuring the cross slide square to the bed. For that I intend to use a faceplate with a dial indicator attached and take a measurement of the cross slide travel. 

Just need to get a dial indicator, oh and I've got my eyes on a ML10 next which I've been informed about so your quite right &#128512;


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## goldstar31 (Sep 28, 2017)

Ah but there is the question of the headstock spindle NOT being at right angle to the  ways so that the lathe will face slightly hollow and then the work will ring together. I'd sort of forgotten that amongst the plethora of often irrelevant information.
I'd been doing a classic series of tests using my J blocks on what of these extremely cheap super market verniers that everyone seems to possess.

Of course, the next interesting thing is not to lean on the tailstock or whatever one does whilst watching the wheels turn.

As the Glaswegians rudely comment-- Is that a fact?

Ooops

N


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## MRA (Oct 12, 2017)

I set up a rather odd (according to lathes.co.uk!) 'Wandess' lathe by adjusting the head across the bed, looking to make it parallel by boring holes until they were no longer taper.  But boring to a nice finish on a small, knackered lathe can be tricky anyway, and tools can be a bit bendy.

Then I set over the tailstock until it turned a straight bar too.  

It made something terrible into something merely rather worn.  I also coloured two of my jaws on the 3-jaw, since a bit of beer can here (but not on the third) made things a whole lot more concentric 

Then someone gave me a Boxford, with everything keyed to v-ways, which is either right or it isn't.  Well, for me it mostly is, but perhaps that's just by comparison from where I've come from!


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