Unknown Lathe. Any Idea's ???

[dickm]

Definitely home-made! Those Plummer blocks bolted to angle iron are a real giveaway. But none the worse for that.
Not sure if Picador did a ready made shaft as heavy as that, but it's quite possible. If it is a Picador, then any thread will definitely be imperial, and probably a standard Whitworth form.

 

[Tony Spear]

If it is a Picador, then any thread will definitely be imperial, and probably a standard Whitworth form.

That's what I thought but 1" Whit is 8tpi and so is the Record faceplate that won't go on!

UNLESS it's the thread angle which is different?

PS: I should have said Plummer block, not Trunnion, but it's been a long time.... :?

 

[Timsk]

I cleaned all the threads with a toothbrush to make sure it wasn't 'gunk' stopping the record face plate going on so I don't think it was that.
I've also used the guide in the axminster catalogue as suggested earlier to measure things and have the following results. Sorry I was born in the age of metric's so as it seems everything in lathe turning is in imperial my measurements may be a little confusing ! as I get confused sometimes talking in fractions !
But they are:
Register diameter 1" 1/64 or 27 mm
Register length 3mm
Thread diameter seemed 1" using callipers
Combined length of thread and register 25 mm
and Thread pitch 1/64th inch or 2.5mm

Any help is greatly appreciated. I hope my measurements are correct I did my best with callipers and an imperial ruler

 

[Tony Spear]

I get confused sometimes talking in fractions !

I can see that! 2.5mm. is approximately 1/10th inch, so the 1/64th. would appear to be wrong.

Do you have a local Engineering workshop or know somebody who works in one? If so it is quite easy to establish what the thread on the shaft is by using a thread gauge.

 

[Timsk]

Yea was a bit dodgy on that thread width that's why I put it in mm as well. I think I will ring a friend that works for a CNC milling company see if he has a thread gauge to make sure I have the correct measurement. May be another matter for the company to allow him to take it home for the night though !
If as said 2.5 mm is 1/10 of an inch looks like I'm going to have difficulty finding a face plate. I've seen them at 1/8 tpi, 1/12 tpi and 1/16 tpi but non at 1/10th tpi. I have been hoping for it to be something like "Oh you need anything that fit's a Myford M8" or "You need anything that fits an Axminster" but C'est la vie it was never going to be that easy.

 

[dickm]

Well, according to my trusty Zeus chart, 1" by 10tpi is BSF (British Standarf Fine pitch, for you youngsters!). You could check this by asking your engineering pal if they have any inch BSF nuts lying around (they'll probably look at you a bit funny, but might have one lurking in someone's spares box )
Not too difficult to weld a suitable nut onto a piece of steel plate to make a faceplate, but anything else will be a one-off special needing a metalworking lathe, I fear.

 

[Timsk]

I have arranged to drive over to see my mate tomorrow. Hopefully he may be able to clear this up for me. If do manage to get a fitting face plate sorted (sorry to sound stupid but remember I'm a newbie at this and have no engineering background) I should be able to get a jaw chuck to fit onto the faceplate as long as the faceplate has standard holes in it for one or other of the common types on sale ?

 

[Timsk]

Well just to keep anyone who's helped up to date. I've been over to my mate at his company and the specialist turner has had a look. No surprise this is not a standard thread for turning as people before have said "thanks dickm etc.." It looking more and more like something thats been knowcked together in the old mine workshops with bits found hanging around. The thread is 1 inch British Standard Pipe ! 11 tpi with a 55 degree insert...
I'm gonna nip back round later to see if they can do anything like re-tap it to something more standard.
Thanks everyone for the help you've given. It's been an adventure. I believe I can get untapped faceplate blanks so that may be the way to go on this one.

 

[Tony Spear]

This gets more interesting by the minute!

I'm really puzzled now - you measured the O/D of the thread at 1" but standard 1" gas pipe has an O/D of 1 11/32" (34mm.) 1" BSP thread is indeed 11 TPI but has a diameter at the top of the thread of 1.309" (33.25mm.), so how on earth did you manage to get a faceplate tapped 1" x 10 TPI (1" BSW) even part way on?

I know this is all a bit confusing, but understand that most threads are defined by the diameter of bar that they would be cut onto. In other words a 1" BSW thread is 1" dia. (near enough) at the top of the thread.

Imperial (and U.S.) Standard pipes however are defined by the nominal bore hence the dimensions given above.

A few more points:

If the information you obtained this morning is correct, it might be possible to get your Record face plate drilled and tapped to fit the thread on your lathe. It might not be a totally accurate fit, but could well be near enough.

If you are getting a faceplate made up or your existing one re-tapped, why not get your friend to make up a screw chuck at the same time - this will increase your turning options even further at very little cost.

If you get a faceplate drilled and tapped to suit - fine, but you may struggle finding a chuck. I know that there are several chucks that are available with interchangeable inserts in the back to fit different lathe threads and that some manufacturers offer (or used to offer) untapped inserts or even one off tappings for non-standard threads. This is probably the way to go 'cos once you're on that slippery slope you're eventually going to want to upgrade your lathe and at least you will still be able to keep your chuck just by buying a new insert.

You appear to have pronged drive centre, which you've been using for the turning you've done so far. Is this on a Morse taper?

 

[Tony Spear]

You appear to have pronged drive centre, which you've been using for the turning you've done so far. Is this on a Morse taper?

I've just had a closer look at your photographs and it appears that your pronged drive centre is indeed on a Morse taper, which implies that despite it having a pipe thread, the shaft or at least part of it, is solid. If so, can you get it turned down to 1" and get it threaded 1" x 8 TPI?

Alternatively of course, you could get somebody to make you an adaptor tapped 1" BSP female and stepped down to 1" x 8 TPI male. I know this increases the bearing overhang but those bearings look pretty substantial and should be OK for anything except very heavy work.

I realise that this is all a bit complicated, but I feel that you are far better off trying to get your lathe to accept standard fittings rather than getting fittings made or adapted to fit your lathe. If you do it this way at least any fittings you buy will fit any future lathes you may buy or if not, will be saleable to other turners with 1" x 8 TPI lathes.

 

[Timsk]

Cheers Tony. Yea the drive centre is MT1 (well I assume this as MT2 does not fit and it looks about 12mm across the hole when I measured. My friend is knocking me up a faceplate this week using 4 inch diameter steel rod they have. He offered but I'm hesitant to ask for much more what with the current climate in his industry. Who knows what the management would say him doing this for me ! I think asking them to make me an adapter with a MT in the end would be a little too cheeky.
Speaking to the lathe specialist he was a bit puzzled by the BSP thread & mentioned it should be longer or thicker (I don't remember which ?) & he did think of re-drilling the Record faceplate fitting a blank inside and tapping that. He said that would be a lot of work though that he didn't have time to do it. He also said the groves looked a little too wide to re cut directly and they would be too brittle afterwards.
Re-cutting the thread on the shaft was not mentioned. I think if he thought it was worth it he would have mentioned it.
I may mention the screw chuck after a few pints another day !
I have seen blank backing plates ready to be tapped somewhere on the internet as I was researching chuck prices. It may have only been for a quite expensive chuck though. I will have to look again, so I may have to search round for a BSP tap and die set ! as my mates place did not have one.
This Lathe is looking more and more like one of the old one off's made at one of the mines workshops there used to be lot's of in my area. They could knock anything up with scrap. Some very talented & ingenious craftsmen worked there.

 

[Bodrighy]

You can get adaptors for different threads and morse sizes so the possibility is valid and as said. If you can get the thread on the lathe to a common one it will make life a lot easier than adapting every chuck, faceplate etc that you get and believe me they will come. Comments about selling on are valid as well.

Apart from all these teetghing problems it does look like a solid piece of kit you have there.

pete

 

[CHJ]

Blank chuck backing plates are usually associated with engineering (metal cutting) lathes.

They are used when an odd or old standard thread match is required or in conjunction with metal lathe chucks to obtain maximum precision of fit.

The bore of the backing plate is machined to fit the lathe spindle thread and register, then mounted on the lathe spindle and the periphery and face machined in situ to give a precise fit in an engineering chuck rear register.

Most wood work lathe chucks do not have this type of rear mounting register (some higher end devices do) it's not impossible to have a backplate made to act as an adaptor between the none standard spindle and a suitable chuck but it would need great care in machining an fit between the two to get it aligned correctly, especially if the spindle does not have a true register collar.

 

[dickm]

If you can get that shaft off (it should drift out of the bearings with suitable pressure and support) there would probably be enough "meat" on the end to turn it down to 3/4inch, and then thread it 16tpi to take "standard" chucks etc. It's the sort of job someone from your local model engineering society might find an interesting challenge......
Certainly easier and cheaper than getting every accessory specially made

 

[Tony Spear]

Tim,

how did your friend establish that this was a BSP thread? Did he use a thread gauge? Or did he just count the threads per inch and make assumption. Reason I ask is that you said:

"he was a bit puzzled by the BSP thread & mentioned it should be longer or thicker (I don't remember which ?) & he did think of re-drilling the Record faceplate fitting a blank inside and tapping that".

If he said it should be "thicker" i.e. larger diameter, that would explain the dimensional anomalies that I described before. If it was a genuine 1" BSP, I reckon you could drill & tap the Record faceplace without any sort of insert as drilling the faceplate bore right out would give you a clean bore of 1" and it should be dead easy to get a 1" BSP thread into that.

For this reason, I don't think it can actually be 1" BSP. Easy way to check is get a 1" BSP pipe coupler or any other female fitting from a local engineering supplier and see if that screws onto the shaft. If it was a genuine 1" BSP, turning it down to take a 1" x 8 TPI wouldn't be a problem. What hadn't ocurred to me before was turning it down to 3/4" x 16 TPI as **** suggests. If the Morse taper is No. 1 there should be plenty of meat in the shaft to do this.

My suggestion of an adaptor doesn't require a Morse taper. What I meant was to get something made that you screw onto the end of the shaft when you want to use standard accessories, but you remove it when you want to use the morse taper. This could be made quite easily IF we can establish what the thread on the shaft really is.

As I said before (and **** M and Bodrighy both seem to agree) I really think you should devote any money and favours to getting the lathe to accept standard accessories rather than getting specials made to fit the lathe.

This all reminds me of what I used to go through back in my professional days. I used to work as an engineer in the water industry and spent years refubishing water treatment plants in various 3rd. World countries. In the 90's I did a load of plants in Nigeria, working from the U.K. on behalf of a Nigerian Contractor I did the engineering in the UK and travelled out there now and again for initial site surveys, progress visits and testing and commissioning the new and refurbished equipment. The work on site was carried out by the Client's local staff and I used to get telexes like "we need a new valve for the filter inlet. The pipe diameter is 150mm. nominal bore and the flanges have 4 holes". Try explaining at 4000 miles range to a young Nigerian engineer that there are at least a dozen different flanges that fit that description and that I need to know a lot more detail and I need to know the length of the valve if it is fitted between flanges!

BUT I managed in the end and I'm sure that between us all we'll get you well up and running before too long!

 

[Timsk]

I realised what you meant with the morse tapper later that night ! I have sent a text to my friend asking if it would be possible to make the collar instead of the faceplate but not heard back from him yet. It does seem the most sensible and the easier thing to do if he can make a faceplate then surely it is as easy for him to take a piece of steel rod and make the collar instead with a thread 1 " 8 tpi to fit the record faceplate on the end so I could use that to fit a jaws chuck as well.
When he measured the original thread he used digital callipers counted the threads and used small inserts to check the angle of the thread (sorry don't know what these are called). Not being an engineer everything else they said went over my head a bit I'm afraid. He checked everything against a laminated chart he had and his Zeus booklet. I think maybe he was also confused as to why a pipe thread was on a solid piece of metal and not on a pipe ! I'm awaiting a call back though to see what's occuring. Again thanks for all your valuable insights. I'm learning a lot !

 

[Tony Spear]

I'm still confused!

If your measuring was anything near accurate and the diameter over the threads is really only 1" it can't be 1" BSP as the root diameter (diameter at bottom of thread) for 1" BSP is 1.193 inches (30.3mm.) which is more than what you've measured the overall diameter at. I can't believe you could be 5mm out!

I think that the suggestion made by **** M is probably the best i.e. get the shaft off, turn it down to 3/4" and get it screwed 3/4" x 16TPI. I realise that this means that your faceplate won't fit but maybe the supplier will exchange it. It will certainly ensure that anything you buy in the future is guaranteed to fit.

To establish what Morse taper you have, insert the drive into the taper. Mark the shank where it enters the taper (a little scratch won't hurt), then measure the diameter at the mark, compare to the Morse taper info that you've already been given and Bob's yer wotsit!

 

[dickm]

Can I suggest that making an adapter to fit on to your shaft is probably not a good idea. The problem is getting absolute concentricity and parallellism between the male and female threads. Sounds easy, and possibly with a big enough lathe, and good metalworking skills it is, but in practice, it's not that simple. DAMHIKT, but at the third attempt my adaptor to fit Bonham chuck to the Myford is still not 100% true .
Cutting a standard thread on the end of your existing shaft eliminates at least half the problem, and would allow you full choice of accessories.

 

[Timsk]

I spoke to my friend today and asked him if he could re thread the shaft to 3/4 inch 16 tpi. He said that probably was the best Idea so I've left the shaft with him to see what he comes up with. Here's hoping he can do it. He said he would get back to me by the end of the week.
One thing I am thinking about is when I get the shaft back and I fit it all in the screw holes on the headstock is making sure it's aligned correctly with the tailstock again. Any tips ?

 

[dickm]

Shouldn't be a great problem, Timsk. Put a centre in the taper in the headstock shaft, same in the tailstock and bring them together point-to-point. Provided your tailstock slides true, and doesn't wobble from side to side between the rails, that should give you a start. But you'll still need to make sure the headstock shaft is parallel to the main lathe axis. Probably the best you can do is to make up some sort of long straight edge and place it parallel to the shaft, then make sure the straight edge is parallel to the bed. You can do that surprisingly accurately by eye. If there is a problem with vertical alignment of the centres, you will have to put shims under the plummer blocks, but, unless its out by a mm or so, I wouldn't worry too much initially.