Yes this seem to be a pretty good resource to learn.
JSR, we talked about the Sherline line, but those Chinese import mini-lathe are a cheaper alternative, sturdier and bigger.
Most of the time they need some adjustments, the quality is not top-notch, or better said the fitting is not that precise out of the box (that's what I've read on the machinists forum, I don't own one). They are a good and cheaper alternative, but for someone that want to invest time in the tool more than the job, at least in the beginning. I suggest you read this web site, and ask me if I can do, or can't do the same operations on the Sherline. So you'll better know its limitations.
The bigger difference Sherline have with a bigger lathe is the lack of power feed. That mean, you can't go automatically from one point to another at a constant feed rate, and more importantly you can't power thread. The threading attachment on a Sherline is basically a set of gear that you install temporarily
outside the lathe, and that link the rotation of the chuck with a precise advance of the tool, giving you a whole range of pitch on any diameter. So it's very precise, but you crank the thread by hand (motor off) ! Slowly, but surely!
I believe schraders have 7.7 mm metric threads
Yes, 7.7mm is uncommon, it is in fact SAE 32 NF thread.
I checked with my thread gauge, and it's referenced here:
http://en.wikipedia.org/wiki/Schrader_valve
32 NF is common, but not really in 0.305" 0D.
In this diameter, it would be difficult to make a inside thread, as you would barely have the place to insert a thread cutter. Maybe you could by grinding a miniature one out of a HSS square bar.
The best way yes would be to reuse the thread from an existing brass cap, cut it's top (on the lathe!) and glue it inside a niceeeeeee shiny custom made cap.
[edit] after a quick look on the web it seems this schrader thread is really an oddball. People have difficulties finding taps for them, the best I could find is custom order here :
http://www.e-taps.com/products.htm
Definitely a good idea to reuse the thread from a valve cap
