Milling machine spindle repair

[Agroshield]

If you spray fuse it, it will be be better than the original.

Sorry, I was talking of the repair as a whole rather than trying to cast aspersions on the welding. The metal that is deposited will be good but there is a whole lot more on top of that. You have to establish a spline profile and cut that profile with no discontinuities to the original, which is quite a challenge. It is a little different to a repair for a bearing, which is static, as by design the pulley slides off the repair and then back onto it.

To the replacement spindle cost he quotes, you'd need to add a replacement pulley as it would be slightly mad to put a worn splined pulley onto a new shaft.

What is wrong with running as-is? Are you getting chatter from cutters?

And there are solutions to mitigate the wear. It is common on Bridgeports. The way they do it is to put a small splined (sliding) collar above the drive pulley with a spring connecting the two so the drive pulley is always pulled into contact with the splines and no longer rattles. This still allows the quill to move up and down. If you can live without the quill most of the time, the collar can just be a plain bore the major dia. of the splines and grub-screwed into the deeper part of the spline. You do have to remember to loosen the grub screw if you want to use the quill.

 

[daedalusminos]

Here's a nasty fix - recut the splines the full length and depth of the wear. Yes it will give a little backlash but nothing worse than you already have.

EDIT
Ideally you'd want to re-finish the driving collar too since un-even wear on that will cause rapid wear of individual splines

 

[Agroshield]

Ideally you'd want to re-finish the driving collar too since un-even wear on that will cause rapid wear of individual splines

Or, if you can, turn it upside down as it will have spent most of its life driving in one direction.

Or invest in a lorryload of left hand cutters...

 

[Morrisman]

Can you put a spacer in so the quill doesn't go back up as far as the worn bit?

Always looking for an easy fix, me.

 

[scottmk1]

I’ve ordered a new hub to go on the splines, that part wasn’t too hard on the pocket! The spindle can’t be turned upside down, it’s got a 40 taper socket in one end as I’m sure you can imagine as it’s from a milling machine.

I don’t think there’s realistically enough meat to turn the existing splines off and press or shrink a sleeve on, so that’s probably a non starter really.

@Brad93 is this something you can repair with your metalizing gear?

 

[scottmk1]

I'd be making a new pulley with thicker sections, machining the splines to suit. I doubt they're hardened.

It’s not a pulley that runs on it, more like a hollow shaft with a dog clutch on the top face which is used to engage the bull gear for the low speed range