Tracy wrote:

It looked like what happens when two pieces of metal rub

together without sufficient lubrication. ---------

  Even more confusing to me was the fact that the spalling

was only on half (of circumference) of sun gear.  It was most severe at

one

point and faded away on either side of this point for about 90 degrees

and

was completely gone on the other half.

Tracy, I had a similar pattern on my Ross sun gear which I believe is
caused by "hard mounting" the planetary gear set, rather than letting them
self align. In essence, the majority of the load is being taken by the one
planetary gear that is closest to the sun gear thereby contacting the sun
gear sooner than the others. Paul mentioned that you epoxied the planetary
gear holder outer teeth to the case which may have caused them to not self
align so that the load is shared equally between all the planetary gears.

I modified my late model Ross (which hard mounts the planetary gear holder)
so that it could move slightly, so that it would self align. So far this,
plus the sun gear oiling change, is working, but I only have about 25 hrs
on it. My gbox temps have dropped as well.

Chuck

 
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