standard sizes are 5-56 thread and 4-40. your store bought threaded pushrods have roled threads. you can tell they'er rolled buy the fact the thread is bigger that the wire and they'er round instead of shap threads. the machine to do this yourself would be cost prohibitive, I'm sure some knows of a cheap roller.

[link=http://members.aol.com/centralrtd/]roled threads[/link]