"Tim Williams" wrote in message
...
Still doing thinking on my Gingery-esque lathe project-to-be... at the
moment I am wondering about tapers.
http://www.motortoolmanufacturing.co...ications.shtml
Says that I could bore maybe a MT#2 in the stock I have... but just what
kind of minimum wall thickness am I looking at? I know Gingery originally
bored a #1 in his 3/4" tailstock ram, and I think same for spindle as
well.
I've got stock up to 1 1/8" dia. (hehe, annealed torsion bar... maybe not
the best for things that apparently should be soft, eh?) which could just
barely fit a #3 with like...nil wall left... but how little is too little?

Oh, and these are pretty precise things too... I have a 0-1" mic (aka
"expensive C clamp") so I could maybe turn some stock to the proper taper
and use that for the reference, but what kind of cheap and easy-to-get
stuff
has a more accurate reference? Speaking of which, I'm not going to want
to
build my own tailstock chuck...hehe...

Tim

Buy a dead center, or a live center, and use it as a gage. Something with
no dings, and a good surface finish. Don't turn something to some ethereal
diameter and taper, than bore the spindle, using it as a gage. You could
end up with something that is totally worthless. Centers are hardened and
ground, usually to the right angle, so would serve as a good gage for
setting the angle that you bore. Careful bluing and checking could yield a
very good angle if you have something that is right to begin with. .
That's critical to a good outcome.

I'd suggest you stick with a #2 taper, no larger for that diameter stock.
It all depends on the size of the threaded spindle I assume you'll be
making. Even that might be too large. A #3 is probably totally
unreasonable. You don't want the threaded portion of your spindle to
bend, do you?

Harold