HTC 400 pallet change problem resolved!
In one of my past posts concerning an intermitant pallet change problem on my HTC 400. This problem has gone on for a couple of years with no clue, just every now and then it would not activate a pallet change to paller #2, you had to push cycle start and it would complete the change and continuewiht the program. MDI, M72 and M71, worked perfectly.
The other day I pulled the covers off on the Z axis for an annual cleanup of the bilge. Low and behold there was a rub mark on the thrust bearing pillow block. A wire, I guess the sensor for the pallet lock, was catching when the carrige was near the spindle while in work, it would rapid back for a pallet change and I guess the shock would break the circuit enough.
My fix was to use a plastic zip tie to secure the wire better, issue has never repeated. I know I should have replaced the wire but I think I will wait until next year.
Just wanted let you guys know the conclusion and a pitch for maintainance. I do have to admit that my plan was to wait until something broke, I just got lucky.