Help on key for 4-jaw chuck needed

[norman valentineParticipant @normanvalentine78682]

I don't understand what all the fuss is. Just make it with mild steel, it will be strong enough. Yes, it will wear out, then make another one. What's the problem?

[pgk pgkParticipant @pgkpgk17461]

Can't you just find a 7mm square drive screwdriver type bit and a cheap holder? Or perhaps some 5/16th square tool steel and grind it down a whisker and fit it into a handle?

I'm new at this so ignore stupid ideas

[Trevor WrightParticipant @trevorwright62541]

Pgk

Not stupid at all, all valid ways of doing it.

The original request was to ask if anyone knew where I could get one off the shelf as this forum always comes up trumps when it comes to the obscure.

Will probably make one from a piece of stainless I found hiding on the shelf.

Trevor

[JasonBModerator @jasonb]

Off the shelf and on this shelf too

Edited By JasonB on 30/12/2014 17:40:39

[Trevor WrightParticipant @trevorwright62541]

Thanks Jason – found the Cromwell tool but is out of stock – will buy the rotagrip at 9/32"

Trevor

Edited By Trevor Wright on 30/12/2014 23:18:37

[Ian S CParticipant @iansc]

Plumbers blow lamp should do it, you only need to heat treat the square end, say about 1 inch, heat to red, and quench, repolish the metal, then hold the key square up ward and aim the blow lamp about halfway down the key, and watch the metal turn blue, and when it reaches the end of the square, quench it again, job done.  This way will leave the tip in a tough, reasonably hard tempered condition, tapering off to unhardened, non brittle steel at the handle end.

Ian S C

Edited By Ian S C on 31/12/2014 12:20:57

[Neil WyattModerator @neilwyatt]

You may even be able to harden it over a gas stove.

Neil

[Enough!Participant @enough]

Posted by JasonB on 30/12/2014 17:35:12:

Off the shelf and on this shelf too

I see they're putting safety springs on these things now too – to protect me from damage due to leaving the chuck-key in.

Now, if they can only come up with something to protect me from the skinned knuckles I get when the chuck key slips out 'cause I'm fighting the ejection spring …. then they'll really have system.

[MadMikeParticipant @madmike]

RDG sell chuck keys for around £8.00 each as I recall.

[chris stephensParticipant @chrisstephens63393]

Hi Guys, all this chat about hardening and tempering, are you lot looking for extra work? Plain old 303 rustless steel in as supplied state is more than adequate. I say 303 because I don't much like rust, if I have bothered to make something I want it to stay pretty for life. Also, I say adequate because the one I made about 7-10 years ago is still unmarked, despite regular use. The only proviso is don't make the square too long and avoid sharp corners where the square meets the round, but do make the square as close a fit as possible to prevent wear.

Happy new year folks

chriStephens

[Tony Pratt 1Participant @tonypratt1]

Posted by Bandersnatch on 31/12/2014 18:17:28:

Posted by JasonB on 30/12/2014 17:35:12:

Off the shelf and on this shelf too

I see they're putting safety springs on these things now too – to protect me from damage due to leaving the chuck-key in.

Now, if they can only come up with something to protect me from the skinned knuckles I get when the chuck key slips out 'cause I'm fighting the ejection spring …. then they'll really have system.

If a person is not clever enough to remove the chuck key should they really be using a machine which uses sharp tools to cut metal?

Tony

[Neil WyattModerator @neilwyatt]

Sounds a good idea – real protection with no real inconvenience.

Makes a lot more sense than the stupid plastic guards that offer zero protection and maximum inconvenience fitted to much kit.

neil

[Mike PooleParticipant @mikepoole82104]

As an apprentice we had a standard chuck key, the spring loaded ones were for anyone caught leaving a key in the chuck. Hats and hairnets were mandatory for us long haired class of 1972 apprentices. After feeling a slight pulling sensation on my hair while using a lathe at tech where the hair nets were not required I pulled back quickly and escaped a scalping, was much more careful after that.

Mike

[Stephen FullerParticipant @stephenfuller]

I think the spring would drive me completely round the bend, would have to remove it.

[Ed DuffnerParticipant @edduffner79357]

I have a spring on my 3-jaw chuck key and thought it would be irritating, but I 've continued to use it and it's surprising how it becomes second nature to expect it there. It also makes you concentrate on what you're doing instead of multitasking with your other hand e.g. grabbing the next turning tool.

[Ian PParticipant @ianp]

How do people with 'spring fitted' lathe chuck keys get on with jaw swapping?

I frequently change between inner and outer gripping jaws and its only a few seconds work because the key stays in the hole and can be spun with one finger through several revolutions. I would hate to have to laboriously keep the key engaged and the first thing I would do is remove the spring.

Ian P

[Ian S CParticipant @iansc]

Ian P, either use the speed wrench from you socket set, my 3/8" one fits my chucks, or make up a driver for the battery drill/screw driver. I have an old battery drill powered by my workshop low voltage DC supply plugged in near the lathe.

Ian S C

[ChrisHParticipant @chrish]

"Makes a lot more sense than the stupid plastic guards that offer zero protection and maximum inconvenience fitted to much kit."

Semi agreed! Semi in that a spring on the chuck key would drive me mad and I would soon remove it, and semi in that the stupid plastic guards do offer zero protection and maximum inconvenience. All the plastic guard seems to do for me is offer a perception of protection, a bit like fitting seat belts to an old (very old now) Morris Minor that was never designed to have them; you think you are safe wearing that seat belt but are you?

The machine being in one's own workshop, with only yourself to worry about, one can always remove said stupid plastic guards!

My lathe, built back in the 1960's/early 70's when people still employed common sense, has no stupid plastic guard over the chuck, or interlock fitted to prevent me opening the cover over the headstock gears and belt drive with the machine running for that matter. I like it that way – wonder how we managed to survive all these years?!

Sorry, this seems a bit off topic, will stop now.

Just for the record, I'm with the "make the key myself" brigade, either using mild steel or a HT bolt, would serve well for quite some time if made properly. When it was no longer good, I'd make another, move on and not think about it anymore.

Chris.

[Trevor WrightParticipant @trevorwright62541]

Update to my original post;…

Struggled to buy one – Xmas and new year shut downs probably – needed to use the 4 jaw so took an 8mm T-bar allen wrench and ground a snug fitting square on it. Crude but functional.

Might just add that I have the habit of clocking to within a couple of thou, and get the final alignment by tightening even more to to high side – hence something tough. Always use thin aluminium packing pieces to prevent damage and it has enough give to get that final alignment.

Re-spring loaded chuck keys – spring is binned immediately – irritating in the extreme.

Trevor

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