MT dead centres

Are the above available with an unhardened Morse taper? I have always assumed they are hardened throughout.

Andrew.

A couple came with my Boxford. Usually called "live centres" for the headstock, as opposed to hardened "dead centres" for the tailstock.

I have some cheap MT2 centres that are hardened and inaccurate! I also bought one made of HSS, Dormer I think, and that's inaccurate too! When I need a centre I use one I turned myself using an MT2 blank arbor, I can always give it another touch up if it gets damaged. The blanks are easily available I think.

Do you want a hardened point but unhardened taper?

Do you want the entire item unhardened?

What should the back end of it look like (tapped for drawbar, tanged, don't care)?

If an entirely soft item will do, use a Morse blank arbor.

If a hardened point is needed, a Morse blank arbor with a hard insert at the front.

Cut the flutes off a Morse taper drill. The taper portion is tough, but not hard. Turn a point on it.

Like John I just turn my own, usually from a bit of steel held in the 3-jaw as with the smaller work I mostly do the side of a jaw is ideal to drive a cranked dog.

If you have ever seen the results of fitters using a large drill's morse taper as a hammer on the blunt end of a drift to release another drill from a machine's socket you would know they are far from hard.

I have turned a point on some steel held in a collet then (carefully avoiding the sharp point) put the 4 jaw over the freshly turned centre. That way I can mount an irregular or large diameter workpiece between centres and drive it by lightly gripping it with the 4 jaws. Most recently I turned some Ø110mm acetal pushed onto a mandrel in this way. No way to do the part with a drive dog even if I had one big enough, you can't get enough grip on a mandrel with plastic and you can't glue it as you can't heat it to release the glue.

Looks a bit like this old one (3) Facebook

Martin C

Thanks everyone,

More than enough information in the above to answer my problem!

Regards,

Andrew.

"If you have ever seen the results of fitters using a large drill's morse taper as a hammer on the blunt end of a drift to release another drill from a machine's socket you would know they are far from hard."

That would explain the marks on one of my inherited drills.

Martin