Help on key for 4-jaw chuck needed

Trevor,

The ratio of views to replies is normally very large, especially for new comments. A good proportion of the initial views are always search engine's 'bots' investigating a new link.

New threads will often show on google within minutes - which I assume means that Google rates this forum!

Neil

Neil, would explain why the views shot up rapidly just after posting...

Got the answer I really expected, ie no-one can name a supplier for that size, many emails also came up blank.

The reason for wanting a non-mild steel key is it is a 10" chuck driven by a 7mm square key.

Trevor

Silver steel, tempered right down to blue?

Neil

Neil,

Lack of equipment, I only have a plumbers blow lamp.

Trevor

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?

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

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

Off the shelf and on this shelf too

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

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

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

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

Neil

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.

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

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

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

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

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

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

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.

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