K72-80 Chuck Disassembly

Evening all, hope well and safe,

I have the 80mm 4jaw and have buggered one of the t-slots for want of a better word. It's just a couple of burrs toward the centre. I'm struggling to explain. I think where I have been ham fisted the leading edge of the screw (for want of a better word) has caught on top of the t-slot due to the load and cased three burrs.

Would any of you kind gents know how I get the screws (scrolls perhaps) out. I can se there are threaded plugs in the rear which will be the way to go. However I'm not sure if threaded (right or left) or just pushed in which I highly doubt.

Excuse my rubbish explanation.

Hi Woody, if it's like a standard 4-jaw chuck, the screws are retained by the plug you can see from the back. The plug has a u- shaped end which locks into a groove about half way along the screw. If you look from the top you should see the groove and the ends of the U at either side. I think there is probably a special tool for getting the u- shaped key out but I've done it in the past with a thin punch- work both sides alternately a little at a time and you should see the plug starting to emerge. To get it out fully you might need to make a punch with a slight bend to get round the corner. I'm not describing this at all well and a picture would be a lot better but all will become clear as the plug emerges.Good luck. Sandy

Photos of both sides of the chuck would help. The  common type are just pushed in with an interference fit. You will probably have to make, or modify a thin punch to knock the offending one out. Before you do that, scratch a line across the plug and the chuck body to help line it up when you refit it. I have removed the plugs from three chucks successfully. Also number them if taking more than one out.

Edited By old mart on 13/06/2020 20:43:07

Thanks guys, I used a bent punch, didn't have to completely remove the yolks, dressed everything up and the chuck is a lot more smooth. All I have to do now is learn how not to tread chucks like a vice!