Made a longer chuck key

[Janderso]

I’ve been wanting to do this for quire some time. To be honest, I wasn’t sure how to cut the square.
Thanks to YouTube and my learning curve reaching a point where tasks like this seem rather simple.
And, it was a simple project.
Question, I used 4140 for this project.
Should I harden the key at the square section?
I’m thinking yes.
What say you?

The pics, I centered the handle rod.
I love these spiral flute quality taps!
I found 4140 a bit difficult to machine until I found the right, sharp positive rake insert and I run them much faster than I use to.
I’m not hesitant to machine it anymore.
The key fits perfect.

 

[DavidR8]

Nice work Jeff!
I think I would HT the end of you can but I'm far from an expert.

 

[benmychree]

If you used 4140 HT, it is good enough as is.

 

[Janderso]

If you used 4140 HT, it is good enough as is.

Good to hear John,
I really didn’t want to go there. I could do a ghetto heat and dunk and try to bring back to straw but, it’s a guessing game.

 

[Janderso]

If you used 4140 HT, it is good enough as is.

John,
I looked up the order from McMaster back in April.
It’s annealed multipurpose 4140 steel rod.
Tough enough?

 

[benmychree]

Not really, for the long haul, but good enough for light to medium use. If I did a qu& Dirty HT, the draw would be closer to blue than straw.

 

[benmychree]

There is no serious reason to avoid 4140 HT, it is fairly easy to machine, not so hard as to be difficult to machine.

 

[projectnut]

I've made a number of them over the years, mostly from 1018, and a few were 4140. I don't have a way to heat treat them so none lasted more than a few years at best. Those made from 1018 lasted less than a year, but that was expected. Oddly enough it's the smaller ones (3/8" & 1/2") that wore out first. Maybe I was just heavy handed when using them, but the T handle was less than 4" across, and I never used a cheater bar or more than 1 hand to tighten them.

A few years ago I picked up several commercially made ones from a used machine tool dealer for $4.00 a piece. I have no idea what brands they are, but they seem to work well and aren't wearing out.

 

[rwm]

I have made several and have not hardened them. Someone (here?) advised me not to, so that the key would wear rather than the socket. They have held up fine for light use. I have never checked a factory key for hardness? Does any one know how hard they are?
Robert

 

[Janderso]

Well,
Right, wrong or whatever, I performed my ghetto DIY heat treat and temper on this annealed 4140.
Time will tell. Based on previous experience, it should be fine.
John York mentioned more of a blue vs. straw. I did the best I could.
When John speaks, I listen.