Finding a chuck key!

[raynerd]

Hello, sorry if this is a  sort of question but it is driving me bonkers!

I`ve got two chucks, one is a tiny 0MT drill chuck, one is a recently aquired lathe 3 jaw chuck and I`ve even got another chuck tonight arriving possibly without the key.

I`ve googled and googled and I don`t see how to identify the correct key with the chuck! for example, the lathe chuck that I have has a 4mm pin and I`ve got a key with a 4mm pin but the leaves are no way near big enough to engage! So clearly there must be more to it than just the pin size..! I know Chronos state pin size and number of teeth but how do you identify how many teeth you need from looking at the chuck? I presume the more teeth, the bigger the key size.

Any help appreciate. Please don`t tell me it is trial and error 

Sorry if this is an obvious one.
Chris

[andyf]

Chis, I suppose you could you work out how many teeth there should be on the key for the little drill chuck by measuring the chuck's o/d across the wide end of the teeth and halving it to get the radius R1. Then measure the distance from the centre of the chuck key hole to the bottom of the teeth on the chuck, which will be (roughly) the radius R2 of the bevel gear on the key you need. Then count the number of teeth round the chuck, and multiply it by R1/R2 and round it down to get the number of teeth there should be on the key (more or less!).

It sounds like your lathe chucks may have bevel gears around them too, so the same calcutation should work for them.

I don't suppose this helps: http://www.newmantools.com/jacobs/keys.htm

Andy

[caskwith]

Go to a tool shop and pick up one of the multikeys, they are usually around a quid and have 4 different size keys in one. Try these and when you have one that fits you can count the teeth.

[raynerd]

Hi Caskwith
I have tried to do this and have purchased two on a whim buy. Each time I get them home, I find the centre pin is too large despite thinking otherwise when in the shop.

Andy, sounds like a plan and I`ll give it a go and see how I get on. To be honest, maybe it is easiest just trial and error after all!

Chris

[Stilldrillin]

Can't you turn down the pin dia, Chris?   

Ah! First, you'd need to hold it in the chuck........   

David D

[andyf]

I think Chris is a  multi-lathe man, David. I don't know how hard the pilot pins are on chuck keys, but they should yield to carbide. An alternative would be to make the holes in the chuck a bit bigger, though that is perhaps the last resort. The main problem seems to be finding a key with the right size gear on it, though.

Andy

[Stilldrillin]

Hi Andy.
Multi- lathe owner? I thought he might be....... 

I reduced, then sleeved a Jacobs pin, the other week...... It were blummin hard! Carbide was a struggle........   

I think the multi type might yield easier, to get the gear into mesh, or not! 

David D

[caskwith]

Hi Caskwith
I have tried to do this and have purchased two on a whim buy. Each time I get them home, I find the centre pin is too large despite thinking otherwise when in the shop.

Andy, sounds like a plan and I`ll give it a go and see how I get on. To be honest, maybe it is easiest just trial and error after all!

Chris

Ahh thats a bugger, guess I got lucky when I did that.

Maybe contact the company that sells the keys, explain your problem and as if you can order all their different sizes that might be suitable and then send back the ones you don't need for a refund. Will cost you a bit of postage but might be the only option?

[Fergus OMore]

As Caskwith says 'Try for one of these multi keys' However, they can be as soft as sh1t and at a quid or less, you should be able grind the spigot down or make a set of insert sleeves - if the outside diameter is right.

You could- well, you could take the Mountain to Mohammed and cart the drill chuck to a decent tool supplier. You live in Manchester so why not someone like Cromwell Tools?

I've a set of them from half inch down to gnat's c*** on a clip rack and every one of my tools has the proper ones as well.

Attitude of mind, my friend, maybe you are just having a bad day.

Good luck

Norman

[raynerd]

Turn the pin down....    I think sometimes I look too hard for an answer!  I`ll give it a bash tomorrow night.

Multilathe owner... Cowells, no less! (as of yesterday!)   

[Mayhem]

When faced with the same problem, I took the chuck into a tool shop and tried the keys they had.  Second tool store I tried had the proper key.

[RussellT]

I had a similar problem and a collection of old chuck keys which didn't fit.

I looked at the chuck and read the maker and model and looked it up on the internet.

It probably helped that it was a Jacobs one - but that was also more incentive to get a key.

Russell

[Pete.]

I guess if you measure the distance from the hole centre to (what would be) the pitch circle on the chuck, double it and multiply that by Pi, you'll get the circumference of the key at the pitch circle. Now see how many teeth are in that distance on the chuck and you'll have your tooth count for the key.

[raynerd]

Well some failure and some success/luck

I turned down the pin on a couple of my multi keys and found that none of them fit the chuck.

However, on a positive, the random key that came with the chuck but doesn`t fit, DID fit the new drill chuck that I said in my original post was on its way and had no key!

It is just this chuck - I just wonder if it is slightly different being a tiny lathe chuck rather than drill chuck!
Chris

[Fergus OMore]

Chris
  Someone ought to tell you that  0 MT only means that you have two pieces of metal but one has a 0 morse taper shank that fits aan unknown drill chuck. All that anyone can guess that it is a little one.

I'm sitting at my desk with a baby keyless  Albrech which holds 0-to 1.5( I presume mm)
Again,  I am sitting with a Rohm 0.5- 4  PJO S1 and that it has a key called Vitrex 1.

What the shanks should be and importantly what the female end of the drill chucks have to be determined - by fit.

Maybe details as above might assist?

Cheers

Norman

[dsquire]

Chris

 
Several posters have sugested that you take the chucks into a tool supply store and try to fit a key from their supply. So far you have ignored them. If you want to play with the big boys, quit being so cheap and spend some money when necessary. Every one of your shortcuts ends up costing you more money in the end.
 
Sorry to come down so hard on you but if you are honest with yourself you know that it's the truth.

Cheers 

Don

[andyf]

Don, you may be being a bit stern with Chris. I live the other side of Manchester from him, and I don't think there are many real tool supply stores left in the city. I would be glad to find one myself. Plenty of places that deal in DIY type stuff and items used in building and allied trades, but I can't think of one which is likely to stock a key for an uncommonly small chuck.

Maybe 40 miles away in  Sheffield, but that would be an expensive trip for one small item.

Andy

[Fergus OMore]

Cromwell Tools as I suggested has a depot in Salford. It has THREE pages of chuck keys.

It's trying when one is trying or when one is trying, one is trying.

Norman

[raynerd]

I work Mon - Fri and a family to sort out Saturday but many thanks for your reply.
Chris

[Fergus OMore]

Yes! 'Work' is a four letter word.

I gave up 35 years ago and it was the worst thing that I ever did.

I should have retired-- much earlier

Cheers

N

Sorry Chris, it was 37 years. Doesn't time fly when you are having fun?

[raynerd]

 
Wife is also 38 weeks pregnant so internet is the only way I'm going to get one or the foreseeable future. Another two weeks and I'll only have evening to my self and even then interrupted!

[RussellT]

AndyF

How about Joseph Gleave, only been there once or twice - but seem to do a lot of stuff.

Russell

[andyf]

Norman, I'd forgotten Cromwells but I wouldn't go there again unless I was desperate.  The chances of getting their cantakerous storemen to produce a selection for Chris to try are slim, even if their stock was actually as extensive as the catalogue ("Can probably get one in for you if you really want, but it will take a few days...").

Russell, Gleaves in Stretford don't seem to have much engineering stuff apart from drills, taps and dies. Helpful people on the counter, though.

Chris, a bit of research here < http://www.jacobschuck.com/images/products/accessory.pdf > shows two small Jacobs keys, one to fit their KO size chuck with a 1/8" (6.35mm) pilot and another for their K1 with a 5/32" (3.97mm) pilot. This page http://www.jacobschuck.com/images/products/Pro%20Keyed%20Updated%20(ENG)-1.pdf shows that those respectively fit the Jacobs 0 chuck (OD 21.6mm, holds up to 4mm) and the Jacobs 1 (OD 30mm, holds up to 6.5mm). If you think yours resembles either of those, Cromwells do list the keys on the third of the pages Norman mentioned.

Andy

[awemawson]

Chris,

You are into making gears - why not turn up a blank and mill one - it must be one of the least demanding (of accuracy) gears to make - even the bevel angle isn't that critical

AWEM

[Jo]

I suggest you ask Colin Childs to put the two missing chuck keys in with your new Cowell's spindle, that way you will definitely get the right ones .

After the £120 you have chosen to spend on (IMHO totally unnecessary) replacement spindle you will hardly notice a couple of cheap chuck keys thrown in.