On the basis that 4 1/2 years late is better than never..

FWIW, a Major with MT..

Decided that a 'ring-immediately-above-the-taper' wasn't going to work for lack of room. Investigating the top of the spindle revealed a recess of convenient dimension to accept 5/8 BSW thread (11tpi) – coarser than I would have liked, but with the reat advantage of being able to be cut in situ without disassembly.

A sleeve nut was bored 10mm, through which was passed the suitably reduced portion of a 12mm drawbar, with a 19mm AF hexagon cross-pinned above to retain it and give a spanner-hold.

Some attempt at concentriicity, squareness and 'fit' are desirable for smooth operation, the spindle bore being long and tight.

It's been fitted for a few weeks and some dozens of tool changes, and has performed faultlessly using a ring spanner c. 150mm long to secure and release the tooling. Nothing has spun and nothing has taken anything harder than my hand to release.

Although at first sight a 1mm land seemed a rather small area with which to eject a morse taper, when circumferential to a 12mm bar it provides a respectable total area that feels both adequate and positive.

It'd be interesting to see if it would hold up for R8 use.

I made the R8 conversion for the Tom Senior self ejecting with a captive drawbar and it has been a great success. I could only do it because there was a convenient cavity in the spindle above the end of the tooling. Also, I could lock the spindle using spanner flats at the bottom end.

Edited By old mart on 08/02/2021 20:35:54

I've recently bought a Warco WM16B milling machine, and it has a built in ejector. If you loosen the drawbar, then turn it a couple more turns it hits the nut / cover arrangement that holds the drawbar in place. Another turn and it ejects the collet holder or drill chuck as the drawbar has come up against a stop at the very top of the spindle.

A bit late, but may help.

/quote Not on my 2019 WM18/gear head George, perhaps that's because it's an R8 taper.
DaveD