Collet

[JollyJim]

Hi y'all,

I've been enjoying this site for a long time, but only just joined as I am hoping
someone can enlighten me on the subject of collets.

Basically, I want the ability to hold wooden dowels from, let's say 6mm up to about 17mm,
rather than using my four jaw chuck. I want the holder to run in my morse taper1 fixing and
I've read so much, that I'm totally confused with ER numbers, straight, tapered,  thread
sizes, nut sizes  etc etc. I presume that collets are much more common within the metal working area, and this
is a subject  I have no knowledge of whatsoever.

If any kind member can spend a bit of time letting me know exactly what I would need
to buy, I'll be kind to my wife for the evening !!!!!

Thanks in advance, also, thanks for all the previous pleasure and knowledge
I have got from this site....

best wishes - Jim

[Bryan Milham]

I cannot tell you what the difference between the ER numbers mean (ER 25, ER32 etc). But if you look at the Axminster catalogue here (https://www.axminster.co.uk/accessories/machinery-accessories/drilling-milling/milling-accessories/collets-collet-holders), it is basically a 2MT stub that is put in the headstock and you can fit different collets depending upon what size stock you need to hold.

Axminster also do a Mini Chuck that screws directly onto the common rance of headstock threads and takes ER20 collets, (https://www.axminster.co.uk/axminster-junior-chuck-ax22446).

[JollyJim]

Thanks dr4g0nfly for the reply. The Junior Chuck looks quite interesting and they do
a version for my thread....I'll give it some thought!!!!!

Incidentally, the reason I stated I wanted one to run in my morse taper, is because
I just assumed that a morse taper would run 'truer' than a screw thread connection,
but, it is just an assumption and I have no evidence to support that theory. Do you have
any thought on that at all ?

Thanks again
best wishes - Jim

[Bryan Milham]

I do have 2 thoughts on that.

1. To hold a morse taper in properly, you do need to actually knock it in with a wooden mallet (try it and see that is recesses further than if you push by hand). Also if not propperly seated, it can come lose - I have experience of Jacobs chucks doing just that.

2. any damage (scrape etc) from a morse taper mandrel twisting in the barrel may cause the collet mandrel to run, just ever so slightly, out of true.

But they are just my thoughts, a true mech eng may know better.

[JollyJim]

Thanks again dr4g0nfly- food for thought...It's mostly for penmaking that I'm thinking and
for other small bits and bobs, but your two comments certainly make sense.

....just love your 'Money does talk, mostly it says ‘Goodbye'....especially to my BossLady hahaha

Regards - Jim

[John Plater]

Apoplogies if I am stating the obvious but......A lot depends on the type of work you want to do. Each size of dowel you want to use would need its own dedicated collet as the tolerance is about -1.0mm on most collets and -0.5mm on smaller sizes. The joy of a collet is accuracy, degree and quality of of grip, speed and ease as well as holding the end of a longer piece of stock with the rest inside the headstock spindle. As you want to go to 17mm I assume that is not a requirement as your No 1 MT is about 12mm at its biggest. My collet arbor is held in an old "c" spanner type of chuck which is not used for anything else as it has been superseded by scroll chucks. If I make a dowel for a piece it can be held very securely without the marking that one tends to get with a scroll chuck jaw but the dowel has to be made specific to the size of the collet. If your dowels are hidden a small scroll chuck might be a better option.
ATB John

[JollyJim]

Hi John, thanks for the reply.

Yes, I had'nt thought of the size of the mt1 cavity imposing a maximum size of the dowel, so, thanks
for that. I mainly will use it for pen mandrels so, would probably only need one or two collets.
Finials and fiddly little things, i could probably make using the same collets.
But, if collets are more accurate, then I would happily gradually buy one now and again to make up
a kit.

Thanks for your thoughts

best wishes - Jim

[happy amateur]

If you have an Axminster chuck you can get Internal jaws 504481 whish will close to half mm and give you full range of dowels. If for pen making get a 1mt pen mandrel which will allow to make any type of tubed pen.

Fred Taylor
orchard-woodturners.org.uk

[JollyJim]

Thanks for the advice Fred,

 I do use a mt1 mandrel but was curious as to whether it would
run truer in a collet.

I suppose what I am trying to decide is whether collets
run truer than tapers, but I'm sure everyone would
have a different take on it.

Thanks again - best wishes - Jim

[BrianH]

Hi Jim
To help you with your confusion about the relative accuracies of morse taper and/or nose thread may I point out that it is NOT the thread which offers the accuracy but the small face behind and surrounding it. Kept clean and undamaged it will offer all the precision you will ever need.

I wonder if you have thought of making wooden collets in order to protect the smile on your bank manager's fizzog….. albeit at the cost of Mr Axminster's? Just about all holding equipment can be safely made using hard wood and initiative, they may not last a lifetime but, hey, you can always make another.


All the best

Brian

[JollyJim]

Hi Brian,Thanks for the reply and that is quite a good idea regarding making your own collet or similar holding
mechanism.

I just realised last night, during a lull in the BossLady's moaning and order-giving, that, my mt1 pen mandrel
is, in fact, a collet holder and collet !!!!! I've no idea if any other collets would fit in it, and still interested to know
what the ER numbers mean, but, I think I'll just take a few paracetemol, lay down and give the brain a rest !!!!

Meanwhile, thanks again Brian, I'll definitely look about making my own..... Best wishes - Jim

[BrianH]

ER numbers... ERRRRRRRRRRRRR, Nope, no idea!!!!!!
Brian

[Redtails4]

Hi
If you really want to know what er collets are and what er stands for have a gander on Wikipedia site have fun bye

[JollyJim]

Thanks Redtails.......

I've just read the Wikipedia site and, although it's like opening a can
of worms, I think I've got enough knowledge to satisfy my curiosity.

..... now, I really am gonna have to lay down......!!!!!

thanks again....best wishes - Jim

[Redtails4]

Hi
Jolly Jim don't stress it's only a way of distinguishing between different types of tapers
And what they are used for if you could not use a pure Morse taper on a router travelling at
28,000 rpm or a r7 taper in a Morse taper socket.it would not fit.
Hope the headache gets better 📣📣📣