Homebrew PCBs

Hi Guys

I am building a small CNC Mill for machining PCB's and was wondering 
what you guys are using for the lead screws on the X and Y axis?  I have 
a small Ball Screw that I am going to use for the Z axis. (10 mm 
diameter)   I was thinking of using stainless threaded rod and split 
nuts made out of brass for the X and Y axis lead screws.   I am using 
Stepper motors and would also be interested in what you recommend for 
pitch.  Would like reasonable travel speeds.
Thanks for the help.

Regards
Bill