Replacement tailstock, sculpture or fabrication

I recently bought a Meyer & Burger UW1, sort of lathe on a stalk that tips up for vertical milling. I am aware of the shortcomings of so called universal machines, I just find old and unusual machines interesting. It came without a tailstock. For a number of reasons (££££ I do not want to buy a new one but if anyone has a spare that my pension can afford, I would love to hear from you. I propose to make a replacement from the solid. I have a choice of steel, which would need to be stress relieved before machining or cast iron. If I make a separate base plate, I can use a block approx 180 X 100 X 50mm. A casting may be possible but it appears that small foundries willing to undertake such work are thin on the ground. Another alternative is to fabricate from steel by either silver soldering or welding. Some forum members are particularly skilled at fabrication and others at carving from solid, I much admire their work. All and any advice much appreciated.

Thank you, Dave

Sorry, accidental smiley.

Edited By daveb on 20/01/2017 17:51:14

What a fabulous machine to find, Dave

It doesn't answer your question, I'm afraid ... but you might like to know that the turntable legend, Arnold Sugden, used one ... which explains the 10" diameter of the 'BDs'.

**LINK**

http://www.progarchives.com/forum/forum_posts.asp?TID=98120

Whichever way you decide to make it ... Make it good.

MichaelG.

In the past when castings were being churned out for tooling described in the latest model engineer mag etc some people wouldn't buy them and fabricated instead. Castings need to be cooler rather slowly and left lying around for a long time to remove stress. It can be a big problem on tooling. I have a home made rotary table that came with my miller. The casting had distorted enough to prevent it working correctly. I took a strap off it and the casting cracked. Curiously the top and bottom is still flat so it still works. All I had to do was relieve it in parts to provide sufficient clearance.

The usual method of fabricating was mild steel and arc welding usually using automotive body filler to form the blend between parts and then painting. Arc welding is likely to be the best option as it's relatively easy to get high levels of penetration and a strong joint. The added material also tends to be applied in several runs which will result in a fillet like shape that might also require a bit of machining.

I've never heard of stress being a problem when things are produced like this. Effectively the casting is fabricated and then machined much like the casting would be.

Black bar contains a lot less stress than bright drawn but would require machining before it's welded. As far as I am aware and I have seen a number of example all were done in bright drawn.

John

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I would have to say arc welding is tricky if you're inexperienced.

Michael W

The thing with castings is the foundries were fetching them out of the sand whilst they were still hot. I instruct my tame man to bury them in more sand once cast and leave them long enough to cool to ambient. I've never had a problem that way.

You can just see the tailstock in Michaels link stood on teh bench just behind the lathe.

Looks like a simple enough fabrication, Flat block at the bottom flat vertical web and a round barrel. To add a bit of shape the base block could easily be chamfered up towards teh web, could even taper the web and then just turn a taper on each end of teh barrel and blend in much like a fishbellied rod. Weld it all together.

There is a guy on another forum who has made some nice tooling by welding and I remember on more than one occasion the part was heated in his furnace after welding to stress relieve it before machining the faces etc. He is also a very good welder, teh welds just needed a light touch with a die grinder and you would be hard pushed to tell they were fabricated rather than the fillets found on castings.

J

More details here: **LINK**

http://anglo-swiss-tools.co.uk/astoba-meyer-burger/

... and on the ubiqitous lathes.co.uk

http://www.lathes.co.uk/meyerburger/

MichaelG.

Edited By Michael Gilligan on 20/01/2017 20:19:10

Hi John, stress relieving is not uncommon for welded fabrications, but is not always needed. However, fabrications made with black bar or plate and sheet steel and also bright steels and stainless steels are virtually always machined after being welded and any stress relieving needed. As welding will always cause distortion, whatever you do to try and prevent it, any machining will be pulled out of shape after welding.

Regards Nick.

Thanks everyone. The machine will swing from 4 1/4 to 17" diameter, Mr Sugden probably thought better of it and settled for 10", at 17" you would want to stand well back when switching on! There is a video on the Astoba site showing the slotting attachment in action, it gave me a good laugh but I don't think I'd want to stand too close to that either. I know about the problems with castings, I would be tempted to bury a new one in a charcoal fire for a couple of hours and let it cool very slowly. Same treatment with a welded assembly. I think my welding will improve now that I've repaired the welder cables, they were down to a couple of strands. Carving and fabrication both appear to be practicable, casting perhaps not, if only on the grounds of cost. I will delay this until the weather improves. Further comments, ideas gratefully received.

Dave

I don't think I even suggested machining before welding but anyway I made a posting a little while ago pointing out the problems with producing stress free castings.

It's vanished into the aether. Hope it wasn't because I gave a clue about where that rotary table casting came from and pointed out 2 suppliers that for me have been ok but it can take years to find out if they are really ok.

Also mentioned the time Rolls Royce left engine blocks lying about - lathe manufacturer's castings too. Plus some of the problems of stress relieving things via heat.

John

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I think I would be looking at buying a secondhand tailstock from another lathe of similar centre height and modifying the base to fit your machine. I can't see in the pics if it is flat ways bed or V ways, but would say a Myford tailstock be suitable for adaptation? V ways could be machined into the base if needed, or if the whole thing was a bit short, a piece of flat steel gauge plate etc bolted and doweled to the bottom to suit the bed.

Otherwise, yes it's possible to fabricate from steel. I made a GH Thomas design versatile dividing head this way. Rough machined the steel pieces to desired size, arc welded them together, heated the whole thing up red and buried it in lime overnight to anneal and stress relieve, then did all the final machining as you would on a normal casting. It worked fine.

A tailstock might not be too hard to fabricate. Turn a suitable sized cylinder for the quill to ride in, with an undersize hole bored up the middle, use a piece of 20mm flat plate for the base, the a couple two pieces of 10mm flat plate to make the sides that rise from base to barrel, set at an angle like an A frame, then a 10mm piece welded over each end of the A frame to form a tapered box structure. Then you have to have a furnace, or those lightweight firebricks and a large torch to heat it red hot after arc welding and slow cool.

The other way with some other tailstock would be to get one even with a lower centre height but with the right size of quill, machine of the base and make a new base for it.

It would need some nice fitting to get the centre height smack on. I think I would be looking for way to drill and ream it from the head providing that is ok and pointing dead straight down the bed.

I have an old 4 or 5" tailstock of a well know german plain lathe that I scrapped off. Kept in case I ever needed to make a larger dividing head. Not an ideal candidate but could be done fairly reasonably.

John

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I think you did John.

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Dave,

Thank you for clarifying that ^^^

Strangely enough ... Until I saw that photo, I had always believed that Mr Sugden used a Myford [which would make reasonable sense of the choice of diameter], but I stumbled across that photo last year, and jumped to a conclusion.

MichaelG.

Edited By Michael Gilligan on 21/01/2017 09:03:41

The bed is flat but the tailstock locates in an off centre T slot about 60 degrees from vertical, similar to J&S bench centres but rather than a lip on the tailstock base, location is at the front of the T slot. The problem with using an existing tailstock is that the cam spindle is where the angled hole needs to be, I've looked at a few tailstocks but there's not enough meat in the casting. I did consider the older instrument makers lathe type but they are scarce and I don't want to cannibalise a good lathe

Ajohnw, I wonder if you would be kind enough to let me have a photo.

Thank you all.

Dave

daveb, where are you based ? I use a foundry in the midlands for small one offs. Sometimes from a polystyrene pattern which is cheap and sacrificial.

Conversion of another tailstock is possible. The hardest thing is to find something that will fit your bed as the width are all different. The second challenge is the vertical height to center of lathe. I Converted my lathe recently it will give you a clue whats involved here **LINK**

Nice work Martin, I had considered the ML10 tailstock, it looks more suitable than the ML7 and Super7 versions which have holes in the wrong place for my purpose. Unless you are lucky though, they are fairly expensive second hand so it's worthwhile to explore other options. If it make the thing from scratch, I can add features like lever or capstan operation of the barrel. Two forum members suggested castings, possibly using the lost foam process. I have PMd them for further information.

Thank you,

Dave

I make lots of parts for Edwardian cars that were originally cast. I get them flame cut from mild steel plate. You can get up to 300mm steel plate.

You can only cut them in 2D, but when comes to machining them I rough them out all over and leave for a couple of weeks to let the stress relieve it self.

Although it has its uses the lost foam process is not without its foibles. One thing to watch out for with it is voids in the casting can be caused caused by the gassing foam.