Chester Champion 16VS mill

Hi, I have a Chester Champion 16VS mill, which looking at to fit power feed to the height (Z) adjustment for the mill head. The crank handle on top, as well as being keyed to the shaft, is held on with long 16 mm nut. A 16 mm grub screw is screwed into the top of this nut, the grub screw is not listed on the parts list or appear in the exploded diagram. Does anyone know the purpose of the grub screw?

Thanks,

Shugs

Hi Shugs. I have already done a power conversion and side handwheel with bevel gears. I fitted a ballscrew as well as the motor drive.

If you want the drawings and info I can send them if you wish.

https://youtu.be/hYPRQU2XSL8

David

Hi David, Thanks for quick reply and kind offer. My use of the mill is quite basic and therefore only need to move mill head when swapping between a vise and a chuck etc., the quill deals with the rest of Z movement. This also means my design is much more basic. I’m using a repurposed cordless drill and a 3d printed coupling, which during trials seemed up to the job. The problem is that the 16mm nut is too long to use with the coupling, a normal nut would be fine but the grub screw is puzzling me, can I do without it?

Thanks again,

Shugs

I can only remember a nyloc nut on the Z handle on mine, Did you buy it new or could it have been altered by the previous owner?

Have you tried using a cordless drill on the nut with a socket? I just used to put a ratchet handle and socket on mine prior to selling, a lot easier than winding the Z wheel up.

Purchased new from Chester, so all as originally supplied. Did the same as yourself, tried a socket fitted to cordless drill, work fine but unscrewed nut when reversed. 3d printed a “what’s it” that fitted over crank handle spokes, that attached to drill, worked well, moving mill head up and down. Reasons of age/health make me want make a more permanent arrangement and it gives me a bit of a project.

Hi I just had a look at the original parts for my mill. It has a long nut and grub screw. To adjust the thrust bearings on the z Axis you unscrew the grub screw a little way then tighten the long nut till there is no play then holding the long nut still with a spanner and tighten the grub screw to stop the nut unscrewing. If you do it this way you don't overtighten the thrust bearings and the nut won't unscrew and you could use s socket to drive the z Axis.

David

Edited By David George 1 on 06/09/2022 10:05:46

These pictures.

David

David, thank you for your reply and photos, it now makes sense, I was weary about disregarding the grub screw. Will now have a rethink, as regard coupling design.

Shugs