I'm describing the taper. Look at the overall length of the same, on the
Nova I mentioned, and you'll see that the entire is not long enough to butt
against the end as you retract the quill in a lot of tailstocks. Seems like
it needs about an extra half inch in length beyond the point at which it is
3/8 or so in diameter.

http://miva3.synergydns.net/Merchant...s-acc-novacntr

I still haven't the foggiest notion of what you're trying to prove. I'm
merely noting that shorter tapers, including those which come with Chaiwan
benchtop drill press chucks, like we have at school, might be the reason
they didn't self eject for the original poster, not his lathe. The metal
lathes at school also have short live centers which require help.

I also gave two easy ways to eject such types.

"AHilton" wrote in message
...
I just posted a picture on ABPW of one type (the most common found on
todays' lathes) of tailstock design with the self-ejection feature. I'm
just using the common bored-through live center design in these pictures.
If needed, I can easily put a Jacobs' Chuck in there or anything else to
show what's going on. Also, I can do a drawing of some other tailstock
designs (that have the self-eject feature of course) to compare and
contrast.

The more I think about George's statement of "You probably have noticed,
at
least once, that the self-ejecting feature is an extension beyond the ~
3/8
diameter portion of the #2 taper." the more he's describing a completely
different tailstock design. And this statement of his ... "Nope. Think
about it. If they're designed to be able to bore through them, they'll
lack
the self-ejector" really suggests that he's just thinking of that one kind
of tailstock self-ejection feature design. He's expecting that "tang" to
be
there on the end of the male morse taper to hit the center-hitting device
in
the tailstock to knock it out. In my mind at least, he's confusing that
tang as the self-ejection feature in wood lathes.