Need Help!- Boss 6 Y axis dead

[timprebleco]

Guy's
I have a Series II Boss 6 machine. It has been running fine for a couple weeks and I started it up yesterday and the Y Axis will not move. All the other axis will. The motor is getting power it is in "brake mode" when powered up. It just moves just ever so slightly when joging but will not turn. I switched out the motor, and the SMD board and still same response. I switched the X & Y leads going to the fuses above the big boards and now neither axis will move. It must have taken out something in the X axis as well now. Z still works though.
Some of the responses from earlier posts suggest bad tranistors. If this is my problem, I would like to know if they are still avalible and where? I have just been given a Boss 5 Machine, so I may have parts. I will ask about it in the next post.

[machintek]

Any time you suspect the transistors, put it in step and step the axis. The transistors typically short, not go open. They are mounted on the door that the SMD boards are on but on black heat sinks (bent aluminum pieces).
Bridgeport specified 2N6547 transistors. There are other posts where this is discussed. They are commercially available. I believe I have about 40 at my office.

George

[timprebleco]

Replaced a set of transistors and am back up and running.
Thanks for the help.