chester conquest tailstock is sloppy, help required please!

[Jonny]

By sticking abrasive paper to both the V and the opposite (flat) side of the bed you will abrade both sides of the tailstock evenly.

This will enlarge the V on the tailstock thereby increasing surface contact, lower the tailstock to the correct height, and at the same time rectify the awful factory finish which leaves very little contact and wavey critical surfaces.

So when you are effectively lapping the tailstock on the bed you are creating extra unwanted problems like it or not.
Angle will be too high.
Rounding of back and front edges even if abrasive is kept very tight, which i doubt. Having less grab than probably what it is now.
A few passes would deem the base scrap.

Better off with a file or scraper and marking blue = no rounded edges think about it. If material isnt required in middle of the dovetail, its very hard not to rub away in front or behind that point. Then add to that equation when rubbing and sliding tailstock back and forth, are you actually moving it every time absolutely cock on level, no twist left or right, no vertical up and down tilting it = Impossible by hand.

[Stilldrillin]

Abrasive on the flanks of the bed V, will make the tailstock V wider. 

Not what you want.......   

David D

On the contrary, it's precisely what you want.

Cheers,
Rich

Oh? 

Ok! 

David D

[pmdevlin]

thanks to all, the good news is that I have been offered help by HS93 member on here, I will be taking the lathe to him, and he is going to check it out, inspect all my bits and pieces, and watch how I do things! then put me right, so watch this space for the embarrasing outcome, I bet its something really obvious!!

I do think though, even in my novice status, the required precision is fine on the headstock end, but sadly lacking on the tailstock end, unless you are an experienced machinist that can sort these things out, and these lathes I would suspect are starter lathes to people like me, so its a bit of a vicious circle, but a learning curve which is good,  it then amazes me how anybody gets any accuracy from the ancient pre war lathes for sale on ebay, thank goodness I didnt end up with one of them!

Paul

[HS93]

,  it then amazes me how anybody gets any accuracy from the ancient pre war lathes for sale on ebay, thank goodness I didnt end up with one of them!

Paul

It wasent for want of trying,  the best one you found and wanted to bid on was pre WW1 I think   :doh

                    Peter       

[GerryB]

G.Day Mate and welcome to the world of the Machinist.
We all started like you finding our way through breakages,bending and generally messing up the project,only we did not have this type of communication to help us.
I have been reading the answers to your problem and they are correct but,i think you should start at No1 of setting up a lathe and that is securing it to the deck.
The way that it is secured and tightened down will affect the level of the bed  (twist)
The 2nd step is to make sure that the Headstock is in line with the bed.
Once these two items are dealt with then you can aline the Tail Stock,as per the Razor Blade test given by Fergus.
The Two screws you mention are the setting screws for the alinement of the Tail  Stock Center,they should be secure,that is not loose.
Usually these two screws are at the rear of the Tail Stock so that by loosening and tightening you can point the business end the correct way.
This is all very well for alining the centers up on a level plane but if the centers are out vertically then you will need an experienced engineer's help.
You mention that you are taking the lathe over to a friend for his help.
This is ok but remember that by unsecuring the unit to transport it you will need to go through the set up again upon returning to your workshop.
It would be better if your friend could come to your place and see your set up.
There a many books out there on the set up of lathes etc.one that comes to mind is the Southbend book on their lathe,
It was started in the 1930's in America but it is correct even by todays machines.
Hope this will assist you,and good luck with your friends help.
GerryB

[jim]

i look forward to finding out the cause of your woes.

have you checked the tailstock at both ends of its travel??

[Fergus OMore]

deleted

[HS93]

The topic has wandered somewhat from a specific problem on a specific lathe to 'mangles' from a WW1 era.
Consequently, I am sort of following the new trend by saying that- there is information still available. I mentioned it - twice, I think, once in Model Engineer after I had restored a friend's Myford ML7. I have no information left as I got snotty reminders of things like copyright and whatever- from stuff that I had written. Bloody Hell!
OK, for those who have access to old Model Engineers, in libraries or clubs, they can still access a sensible DIY series of articles by the late David Lammas who retored a pre-war Myford. As best that I have it, it appears in a series of articles dealing with scraping first and then going on to lead and feed screws which appear on 4th November and 2nd December 1988.

I've rambling a bit but a further bit of research reveals that modified tailstocks are currently available. Whether or not, others regards them as pricey is not the issue. The price is filling the car tank with fuel-- which is where I am going to now!
Bye!

so what has model eng and you restoring a ML7 and Petrol got to do with it , I was responding to Paul where he was saying he was glad he had not bought an old lathe, I was just reminding him of one he was looking at

Peter

[Fergus OMore]

I was merely - or so I thought, of continuing the idea of setting off to restore the accuracy of a lathe after reading that the writer wanted to set off with a lump of emery paper! At least, my reference pointed at one way of doing it- and succeding.

If my 'contribution' is troubling others, please do what I have attempted- and deleted it as best I can.

[HS93]

I was merely - or so I thought, of continuing the idea of setting off to restore the accuracy of a lathe after reading that the writer wanted to set off with a lump of emery paper! At least, my reference pointed at one way of doing it- and succeding.

If my 'contribution' is troubling others, please do what I have attempted- and deleted it as best I can.

I cannot see anything wrong with your helpful posts,

Peter

[loply]

By sticking abrasive paper to both the V and the opposite (flat) side of the bed you will abrade both sides of the tailstock evenly.

This will enlarge the V on the tailstock thereby increasing surface contact, lower the tailstock to the correct height, and at the same time rectify the awful factory finish which leaves very little contact and wavey critical surfaces.

So when you are effectively lapping the tailstock on the bed you are creating extra unwanted problems like it or not.
Angle will be too high.
Rounding of back and front edges even if abrasive is kept very tight, which i doubt. Having less grab than probably what it is now.
A few passes would deem the base scrap.

Better off with a file or scraper and marking blue = no rounded edges think about it. If material isnt required in middle of the dovetail, its very hard not to rub away in front or behind that point. Then add to that equation when rubbing and sliding tailstock back and forth, are you actually moving it every time absolutely cock on level, no twist left or right, no vertical up and down tilting it = Impossible by hand.

I see where you're coming from, but this is a tried and tested method, even used on the saddle as well as the tailstock - see here for example http://www.kahale-martinapmachine.net/navigation_bars/nextpage.html

If you want absolute perfection then extreme care must be taken, or the part could be hand scraped, but perhaps you're not familiar with how rough these parts are to begin with, they are bordering on requiring re-milling to sort out, hand scraping would take a long time. More or less anything will be a major improvement, and certainly with care lapping on abrasive paper glued to the bed with tape is a good method, it solves 3 problems in one go - tailstock too high, tailstock V is not straight and parallel, finish on the tailstock base is extremely poor.

If you are worried that the tailstock would end up tilting (ie not standing straight) because you took more off the V than you did off the opposite side, well these tailstocks feature a sliding parallel adjustment which effectively slides the centreline of the tailstock back and forth in the same direction as the cross slide, allowing you to correct for this error, which is most certainly present from the factory anyway.

[Fergus OMore]

As we have yet to receive an update, may I mention that GadgetBuilder's site is 'doing up a tailstock' for a 7x12 lathe which is probably a Chester Conquest lookalike

[pmdevlin]

no update until its been done, 

[pmdevlin]

Its been a while, but I have to own up to my embarrasment. Last night the lathe was at a friends, who knows what he is doing , he could not fault the tailstock operation, after a lot of head scratching, and taking things on and off,  we then used my drill bits, oops! looks like it is my rubbish drill bits that caused the off centre drilling, what a fool I am!