Material for Collet Holder

I want to make a ER16 collet holder for my tailstock.

I have a piece of meehanite bar just the right size for it.

Is this a wise choice of material? Would I be better of saving it for a better application and use mild steel instead?

Cheers,

Steve

Is it worth messing about making one when you can get one for just under £30.00+postage you also get the nut as well for that price.

All my ER32 collet chucks are made from steel

Edited By Dalboy on 30/05/2023 16:20:25

when I made mine I used USACUT55 which is a type of 16T and seems to be ok.Theynwere for a taistock turret.

I need to make one to fit the adjustable tailstock tool holder on my Sherline lathe.

Take a look at commercial fireguards. Do you see any that are made of chocolate?

Now take a look at commercial ER collet chucks and see from which material they are made.

Thank you for one of the most unhelpful posts I've seen.

Maybe you think it was a stupid question but it was a genuine query.

I'm not making a commercial collet chuck. It's for a Sherline bench top lathe.

If you can't answer informatively and politely, don't bother.

Steve

For all the ER collet holders that I have made, mild steel has been the material, and since relative movement is limited and at extremely low speed, so far the six or so "specials) that have been made, none have caused any problems.

I did take the coward's way bout and boughtb the nuts (Er20, ER 25 and ER32 )

I suspect that Mehanite being a cast material is likely to be less strong, when subjected to the outward forces required to close the collet, than mild steel.

Howard

Thank you Howard for a sensible answer.

I asked about the cast iron just because I had a suitable size lump.

I intend to buy the nuts as well. I do have some EN1A but I wanted to avoid getting the hacksaw out!

Steve

Dalboy, I made 7 and the nuts were £22 and the material was in stock plus how much is satisfaction per hour?

I have mixed views on any form of cast iron.

Easy to machine

BUT although strong in compression, it is weak in tension.

Dirty to machine; the dust gets everywhere. (A powerful magnet under a shee or sheets of newspaper catches a lot, but not all, of the swarf. This makes cleaning up and disposal easier.

Just make sure that the newspaper or sheet does not become in involved with anything rotating!

Howard

Considering the amount of use any home made tool for model engineering will get in its lifetime, or our lifetime, I don’t think it matters at all what material you make them out of, you are not going to wear them out. If you have a piece of material handy, use it, if it works that’s great.

My concern would be a relatively fine thread in cast iron - it's ok for a coarse backplate thread, for example, but closing nut threads take a fair load.

I'm going to be using mini nuts as well - an even finer thread, M19x1.

I think I'll get my hacksaw out and use mild steel.

I would use mild steel as I would be very doubtful that the cast iron threads would be strong enough. Colin

Hi Steve, when I owned a BCA Miller I made 2 er collet chucks and the material I used was what used to be known as EN24T now 817M40 it's a high tensile steel but machines well and should have all the strength and wearability needed

I've recently bought a bunch of ER11 collet holders from Aliexpress. the one I've measured so far has a run out of 12 microns, which is OK, I think.

They are actually decent quality on the whole, and quite ridiculously cheap. For a tenner you can get 2 or 3!

One word of warning - some of the reviews and my own experience indicates that the holder proper is pretty nice, but the nuts can be subject to burrs. Seems random, so maybe buy a couple of spares.

I think you can also get them from Amazon for a little bit more.

Iain

Steel is going to flex rather than crack when subjected to the forces of the taper on the OD of the collets being forced home by the nut. Definitely go with steel.

Save your meehanite for a use where it is advantgeous: bushings, gears etc.

I agree with Hopper - if you have a mishap, cast iron is likely to snap, just like that, while steel will bend. Good steel (like most of the bought ones) might be so strong that damage will be done to other parts, and needs careful heat treatment, so for 'delicate' use on a small lathe (etc) mild steel should be a good choice.

Cheers, Tim

I made a couple of ER25 chucks from mild steel about 15 years ago, one for the mill and one for the lathe. They get a lot of use, but they are still going strong and remain accurate.

It’s well worth while paying a bit more and buying ball bearing nuts. The tightening torque for good grip is considerably less. Particularly important in the mill, where I’ve never knowingly had a cutter slip.

Mike

Rather than make the complete holder and having to select a suitable material, would it be possible, to modify an existing commercial holder by adding the tang or whatever is needed to fit the tailstock?