Cromwell S800 Mk3 lathe

Thanks Michael, I'm afraid it will slow down now as I am working long hours now for the next 4 months. However I will keep it ticking over. Got some tail stock tooling and a knurling tool also a set of imperial taper pin reamers and a left hand 3/8" ACME tap. Some bronze should arrive soon for the cross slide nut and a steady finger. Finished off the switch housing.

I'm still working long hours and will be away on location filming all around New Zealand, almost a paid holiday really. In a couple of months I will do the final push on the Cromwell and finish it off.

Hi Rod, I am new to this site, joining after having found your Cromwell rebuild project. First my congratulations! You've brought new life into another piece of great British engineering having faced quite a few challenges along the way! Well done!
I have just acquired the same lathe and am now assessing what I have and what I have to do! My lathe came without the stand and motor, so for sure I have to consider what to do about that at some time. There are a few points I am not clear about so far, particularly about the headstock adjustment / disassembly. Before I launch right in, I hope you might point me in the right direction? At the moment the Bronze/Brass thrust end caps (the visible castellated C spanner ones at both ends) are not 100% tight. Should they be? I can rotate them just a bit either way by hand, but they cannot be undone by hand. What holds them tight? I have a cross section drawing from the manual but its not really conclusive on this so any advice would be appreciated. There appear to be a few differences between our lathes, a bit of product development I think. The base for my compound slide is a gunmetal casting, and not cast iron for example. Mine is number 946. Apparently there were only about 350 made, so quite rare as you know. I hope to hear from you.
Paul

Hi Paul sorry for the belated reply. How have you got on with your machine? I will be redoing the belt on mine so will reacquaint myself with the head setting then.
Have ordered a new belt from Lathes UK also more taper pins and some U screws to hold the Gearbox plate on.
First job will be to make set screws for the hand wheels. Once they are done I can get the outstanding chrome work done.

RodF said:

Hi Paul sorry for the belated reply. How have you got on with your machine? I will be redoing the belt on mine so will reacquaint myself with the head setting then.
Have ordered a new belt from Lathes UK also more taper pins and some U screws to hold the Gearbox plate on.
First job will be to make set screws for the hand wheels. Once they are done I can get the outstanding chrome work done.

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Hi Rod, and thanks for your reply.
The lathe is coming on quite well now. It has presented challenges, the tailstock and gearbox were not original to the bed it seems, so that has taken quite a bit of alignment and fettling. I have had to make a stand, fabricate an underslung motor with VFD and make several parts that were missing, along with all the small stuff like replacement sight glasses, wicks etc. The headstock is sorted now with new main bearings. I had it spinning under power for the first time yesterday, and am really impressed with how smooth it runs, and that was without oil in the headstock! This one had a conversion to use a link v belt drive, and I've stayed with this, although there is very little clearance under the backgear engagement rod. I'll make a judgment call on whether or not to go the extra mile with re-chroming - this was only intended as a spare to use while I can work on my other lathe. There appears to be a small amount of wear in the bed, I would guess around 0.002" along the length, which makes the saddle a bit stiff near the ends. I may have to make some compromise with the saddle gibs. On the whole you can't fail but to be impressed with the build quality, more or less hand made I would say. The tumbler reverse box is a work of art!
Will try and send a pic later. By the way - what are U screws? Cap heads? Socket heads?
Regards
Paul

U screws are rivet like screws to be hammered into unthreaded holes. They are to hold the gearbox lever indent plate on. Had to buy 100 for US$14 with $25 postage.

U screws, belt and taper pins arrived. I now have enough U screws and taper pins for 10 machines.

Making thumb screws for the hand wheel dials. I need to brush up on knurling. once these are done I can take a few things to the chrome plater.

Didn't really think the process through so I had to buy a 3/16" BSF tap and make a mandrel to hold the screws for knurling. The result was a bit fine but I prefered that to the next coarser cut. Original is on the left.

On the cross slide wheel.