[TowerTalk] Hy-Gain T2X Mechanical Failure

[Mike]

Hello,

What could cause a gear shaft in a T2X to fail - shear off?  The symptoms 
of the problem were: The T2X, used to turn an EF240X and 4 element SteppIR, 
was removed yesterday after it started to slow down in turning in the CCW 
direction.  It turned at a faster rate in the CW direction, but when it's 
motor stopped a loud metalic noise was heard prior to the brake set 
sound.  The problem was one of the gear shafts had sheared off.  All the 
gears are okay and no other mechanical damage could be seen.   A spare T2X 
was installed and operates okay.

The gear shaft sheared off inside of the base casting.  No telling how long 
the gear shaft was in the sheared condition before it worked out of the 
base casting.  (A part of the gear shaft could be seen inside the base 
casting - so the gear shaft didn't completely come out of the casting.)

The T2X was purchased used about 8 years ago (part of an estate sale) and 
had been in use at K4GMH for 7 years.   Fifteen months ago it was part of 
the tower (130 feet) that collapsed due to Hurricane Isabel causing an 
eighty foot pine tree to fall across a set of guys.  The T2X was overhauled 
and reinstalled on the new tower and had operated okay for the previous 
five months.

Any ideas on what caused the gear shaft to shear off?  Don't want the 
problem to happen again.

         73,
         Mike, K4GMH