Hardinge HLV-H Threading Problem.

[GeorgiaDoc]

Threading on my machine has been going fine. Went to do some threading today and the carriage will not move in the right to left direction when you engage the threading handle. The knob is turned to thread, the half nut is engaged, but the carnage will no move. it will move left to right but not right to left. Any ideas? I am a fairly novice hobby machinist so this is not my typical realm. Any help is appreciated.

 

[Billtodd]

Check,
Lead screw shear pin, by checking the rotation of the front change-gear shaft. (It is connected to the lead screw with said pin)
Motion of the dog clutch levers : the end of the sliding shaft is visible at the change-gear end ( wiggle the lever you'll see it move) , check that it is moving in and out the same distance from centre . Check that the left and right thread stops are not stopping the motion of the thread lever.

Pray, that the dog clutch is ok and that it hasn't lost a dog.

 

[GeorgiaDoc]

It was the shear pin. Thx!!