Member postings for David Scothern

Right, I've understood my rather basic mistake - my calipers are graduated in decimal parts of an inch, not eighths - so just over 0.3in (i.e. 5/16) rather than 3/8. Lesson learnt.

Anyway, aside from demonstrating my incompetence, and by way of rendering this thread useful for anyone searching in the future, the good people at Colchesterspares.com confirmed that the bolts are 5/16" UNC.

Thanks again to everyone for your patience and advice!

I've been back and found the longest of them - I'm still coming to 18tpi. I think it was my hasty measurement of diameter that was off - 5/16" rather than 3/8". 5/16x18tpi looks a bit more reasonable.

Thread gauges would be a good idea - and some basic competence with the calipers would also help!

In which case, I've obviously miscounted! I got 9 threads in 1/2". Definitely not 12, so let's go with 8, i.e. 16tpi.

Happy news - the vertical slide came with four mounting bolts, which happen to match the threads in the cross-slide! I still don't know what they are, but they're 3/8" over the thread x 18tpi.

Edited By David Scothern on 11/05/2018 19:21:18

Hi all,

I’m looking to remove my Mk1 round-nose Colchester Student’s cross-slide in order to do some work on it. I’ve previously removed the handwheel, cross-slide feed shaft etc to deal with backlash, but I didn’t manage to get the cross-slide off the lathe entirely then and am not sure how to go about it. Has anyone done it, and if so, how?

Thanks in advance and best regards,

Dave.

Many thanks - will look for some Whitworths and find out!

I've got a round-nose Colchester Student. I'm looking to adapt a vertical slide to give me occasional milling capability. I hope to mount it to the cross-slide via the rear toolpost threads. Does anyone know what those threads are? They're round about M8 but I'm assuming Imperial. The manual itemises the bolts but doesn't say what they are. I'd be grateful for any advice.

Thanks in advance,

Dave.