Been using Mach 3 for about 2 years and have two different cnc routers. Recently the z axis on the one router will begin cutting correctly then when it moves up and goes to another part of program it stays up in the air and cuts nothing. Never returns back to the original z zero position. I've tried everything I can think of: reinstall, motor tuning. checked servo's, driver test. It keeps happening; even tired different programs (that I've run before) and nothing.
HELP!!!
Justin