I have recently purchased an old Bridgeport series I v2xt. It has a SX15 controller I believe. I have been learning a great deal about this machine through reading the manuals and this forum but have been having some problems that I cant seem to figure out. When I first had the machine installed and hooked up, it worked great. I was able to home and dry run a program, the next day as I began to home it the Z axis got jammed and I figured out how to fix that thanks to this forum. Unfortunately something has run amok and the z axis wont let me even get to home the machine. As I enable the axis drive it will begin to move slowly up and it doesn't stop until it hits the limit or (home switch?) its the upper most switch. It then gives me an a message, AM Zap from SAF. So ok well I ignore that since I don't know what it means but im sure its significant to my problems here, and I go ahead and re-enable the axis. It tells me to jog Z off the limit so I do that but if I jog too fast downward it will give me another message and shut off, AM Z tach disagrees with command. Now since I have it off the limit I enable the axis again and ignore the fact the Z is creeping upward and try to home the machine. If the quill is close enough to the top it will zip upward and get stuck or if its more than a few inches down it will give me the tach error again. Does this make sense to anyone? Help would be much appreciated!