Boxford Lathe Big Bore Conversion

Does anyone know if the commonly encountered Boxford lathes can be modified to increase the spindle bore from 0.75" to, say, 1" or even more?

I know that some of the later ones such as the VSL could be had with 38mm bores or thereabouts.

The X10 series Boxfords (250,280,330, 10.20, 11.30 etc) have a 35mm bore spindle.

Would it be too forward of me to mention that my 280 is for sale in the classifieds?!

The OD of the extreme end of the spindle on my ME10 measures 1.050", That measurement is also the tooth root diameter of the gear machined on the end of the spindle.

A 1" bore wouldn't leave much metal there.

Can't say how close you would get to the bearing inner races though.

I have asked Boxford this question and they said "Its not recommended to increase the bore of the spindle". I can measure a spindle from an "A" tomorrow and see how much wall there is. Cannot remember from my last foray into this subject.

.

If it was a good idea then I presume Boxford would have done it themselves as a bigger bore is always a good selling point.

Nick

Further to my post above, a bit of googling suggests that the ID of the bearings is 35mm, or 1,379".

leaving about 0.188" for a 1" bore. A bit thin I'd think.

Many thanks for all replies to my question. It looks as though there is no easy answer without a major rework.

Since the Boxford is a modular construction the bed runs right through under the headstock. Therefore you could make a new headstock from plate even a DIY aluminium casting, and fit it to the main part of the bed. Then line bore for your new selection of bearings. Moving it over to the headstock position should retain the alignment (assuming good condition bed). Probably worth basing it around the spindle of a 10" far eastern design if you can find one that has spares available. Would be an interesting article on MEW.

Thanks for your very interesting suggestion Bazyle, I did wonder about doing something like this. I'm not too familiar with Boxfords but would it be possible to do something similar by obtaining a spare headstock and boring it out to take larger taper roller bearings and either obtain or make a suitably larger spindle. If suitable roller bearings are not obtainable would plain bearings be OK ? Could the bull gear and pulleys be bored larger to suit the fatter spindle?

Been there,started but gave up.

**LINK**

Parts were to heavy for my old and wellworn back and the lathe where spindle comes from is cheap

https://www.hbm-machines.com/producten/metaalbewerking/metaaldraaibanken/metaaldraaibankensub/hbm-290-vario-metaaldraaibank

Edited By Niels Abildgaard on 13/08/2017 18:57:21

If you have a one off, or occasional need for the larger bore then it might be better to find an evening class or club with the bigger machine. If it is more frequent then it is probably better to get the bigger lathe anyway. Although Niels may have some more info I'd be surprised if the basic headstock would have sufficient extra metal around to bore out.

There is lots of metal to bore:

**LINK**

The original front bearing is 76.2 mm dia and the new proposed is 90mm.

Thank you Niels for your link to the Far Eastern lathes. I think the one which would suit me is similar to a Warco WM280V here in the UK, but the price is almost £3000 which unfortunately I am unable to afford. Anyway, I do enjoy a challenge and would like to further examine the modified Boxford idea. What bearing did you have in mind for the bored out headstock with an O.D. of 90mm? And which spindle would be available ?

Brian, Neils was directing you to the lathe that the larger spindle was sourced from as a spare part not suggesting you buy a whole lathe. Though the same 290 lathes are available with D1-4 mount which would be even better than flange mount.

If you wanted to stick with 1" bore then the 280 spindle would do and I think my bearings for that are about 70mm OD

Edited By JasonB on 14/08/2017 19:37:21

Hello Brian

I bougth the spare chinese spindle plus unused bearings and a used Boxford headstock.

I have sawed the rear part of headstock away because I need no back gearing.My present backgear is only used for unscrewing chucks.

Putting headstock on saw made me realise that I was to old for lifting things.

I then realised that I could have a complete new lathe from Holland for 2400€.

I will stick with my much improved Boxford.

You can have the parts for postage and a  gift to a dogs home

Edited By Niels Abildgaard on 14/08/2017 20:54:03

Edited By Niels Abildgaard on 14/08/2017 20:54:50

JasonB

I have sent you a P.M.

MichaelG.

Niels, I have sent you a p.m.

Regards,

Brian

I should have referred to the Warco 290V in my earlier post and not the 280V; a slip of my typing fingers I'm afraid!

Brian

Another possibility might be to take a look at the Australian made Hercus lathes, which like the Boxford, I believe, are a clone of the American South Bend 9" lathe. Hercus made a model called the 260 where they took the basic model and fitted it with a larger spindle supported in a larger headstock that sat the spindle an inch or so higher than the standard 9" lathe. Tailstock and topslide were fitted with thicker bases to match.

If they are all based on the South Bend dimensions, a Hercus headstock and spindle should fit your Boxford. If you google around there are plenty of Hercus parts available still. Here's a brand new headstock complete with gears etc and spindle for A$485. **LINK**

The fellow who runs the linked business is quite helpful and may be able to tell you if the 260 spindle and bearings could be fitted to a modified 9" headstock.

Edited By Hopper on 15/08/2017 00:16:54

Edited By Hopper on 15/08/2017 00:18:30