Made A New Chuck Key

[Chipper5783]

I really must compliment mattthemuppet.
I liked the sliding handle chuck key that he made,
http://www.hobby-machinist.com/threads/stubby-chuck-key-for-4-jaw.41788/#post-359028

so I copied him (which is intended to be a compliment). My application is for the chuck on my dividing head. The way my little mill is set up, the tooling is generally held in collets that go right up inside the spindle taper. That holds the tools great, it keeps everything very close and about as stiff as one can possible get. That also means that the regular chuck key doesn't go round with out running into something (the key is common with one of my lathe chucks - and of course none came with the dividing head, being something I got at an auction).

So, I finally pony'd up and made a stubby key with a sliding handle. Instead of Matt's fancy little button arrangement (which is very nice and looks really sharp), I made a little land on each end 0.025" oversize.

The handle is a scrap of drill rod, with a reamed fit in the body. I ran a bit of AlOx cloth to get it to slide nice.

 

[toolroom]

Very nice and very professional. Did you heat treat the key end?

 

[mattthemuppet2]

super neat and thanks for the ref, it's great to see ideas spread and be used by others. I find mine really useful, though I have to say the finish on yours is way better than mine I'm guessing that the handle is a light press fit to get it in the key, then the oversized ends don't let it escape?

 

[Chipper5783]

I have not heat treated the key end. I have made 6 chuck keys - sort of weird because I have 7 chucks that use a conventional key. True confession, I made two keys for the collet chuck. I get most of my kit second hand - the little pieces are inevetably gone. In otherwords of the 5 chucks that I got here and there, none had keys. There is very little commonality of key size.

I do fuss with getting a good fit of the key in the square hole - I make the square to fit with 0.002" - 0.004" clearance, and then round the corners to match the shape in the chuck. Having a good fit, makes it easier on the tool and the pinion/screw. On my little lathe, it came to me with the spindle cams split open, because a previous owner used too small a square (which wedges the cam open).

It is not like the key gets used for lots of hours, I expect non-heat treated it will last a very long time. I also don't think I need the extra strength - if the key square is getting twisted, then I'm probably over tightening. So far I find I can give it a pretty good torque and no issues.

 

[Chipper5783]

I though the sliding handle with the larger ends was pretty clever (I'm easily amused). Photos attached with the rest of the story.

Obviously the first end was straight forward, the second end, with the chuck body in place took more time (effectively it was quite a ways out from the chuck).

 

[mattthemuppet2]

very neat - there's more than one way to skin a cat!

 

[Cheeseking]

LOL! Nice

 

[RIMSPOKE]