Chuck stuck on spindle....Help

[DaveH]

Well done

DaveH

[Micktoon]

This is the story of how the chuck was removed

I already had a boring bar I had made and a quick change tool holder that would hold it. The basic plan was to drill the end of this boring bar and make a parting tool incert to fit in the end of it that would align with the very rear edge of the backplate just short of where it mated with the spindle shoulder.

Thes shots of making the bar are in my mate Daves workshop, using hid Kerry AG lathe and Emco FB2 mill, cheers again Dave.
Centre drilling the bar


Drilling the bar for the incert to fit


The incert test fitted in the bar, this was something Dave had lying around so just needed altering as it was already roughly what we needed.


The side of the bar needed milled of for clearance and the other side was milled flat, drilled , tapped M6 and grub screws used to lock the incert in place


This is the new tool in the holder lined up for action


Note the DTI this was to gauge how far the tool advanced to make sure it did not mark the spindle


So far so good , just going slowly, once it was only a fracion to go, I tried putting bolts back through the backplate and the slightest of taps loosened the B*****d


This is the backplate after its surgery, just as planned , the spindle not touched but the stress locking the thread releaved so free


The spindle survived the ordeal


This it the blow hole in the casting that has been threaded, soon as I saw this I remembered it was like this before, it was like this when the chuck came with the lathe and has been used many times, do people think this is what will have caused the problem and is it savable by filling with metal putty and reshaping or bin it ? bearing in mind its either hassle or expensive to get a six inch backplate.



So at least someone else will be able to use this method to remove a locked on chuck without damage .........the back plate has enough 'meat' to be used again if its repairable too. Thanks to Willie 'Highpower' too for telling this basic idea had worked on rifle barrels which swayed me to go ahead too.

Cheers Mick

[DaveH]

Nicely shown Mick.
I wouldn't bin it, I would just clean it up (carefully) and use it as is. I wouldn't use any metal putty. I also think it may be a good idea to try it out a few times on a dummy spindle thread first.

DaveH

[Highpower]

Very well planned and executed Mick!
Glad to see that is behind you now. I'm with Dave though - no putty.

[Mayhem]

Nice work Mick.

[f350ca]

Nice save Mick. Hope that wasn't the first cut on the lathe.

[Micktoon]

Hi Lads thanks again for the in put, I think I will have a proper look for a new back plate first then if I can not get one think about making one and only use this one after making a dummy spindle nose to test and teast this one again on as I will be kicking myself if I get it stuck again and damage the spindle threads.
Greg it was the first cut lol, I was not even at the stage to cut anything when it was found that the chuck was jammed on., so it was desperate times call for desperate measures .............. so the first cut but I hope not the last

Cheers Mick

[dallen]

keep the plate, fill the hole with something like silicone to keep crap out of it and reface it for use

must of had a chip in the hole when you put it back on the lathe.

Nice save, sometimes we just have to do what doesn't seen the right thing to do, but is the only way get done what we need to do.

DA