Yep, the guys who say that you need to change some gears to cut Imperial threads are correct, as the leadscrew is 3.0mm pitch. Metric leadscrew = designed to cut metric threads, as a rule.
Like this set, to cover the full range;
http://australianmetalworkinghobbyi...roduct&path=39_44&product_id=176That gives you the actual tooth count of these gears, so see if you got any of them in the bits box.
Edit: There are some great downloads on the basics of metal lathe use [and mucho other useful/interesting metalworking stuff] at
http://www.metalwebnews.com/mr.html I'd suggest 'How to Run a Southbend Lathe' and 'Text Book of Turning' for anyone starting out. The latter describes the use of those extra bits, like the steadies etc. very well.
