On Wed, 25 Apr 2012 11:34:02 -0400, "Flying Pig"
wrote in part:

Has anyone had experience in out-of-round shafts to say whether the standard
packing will do its job? If I were to do a lot of shoeshining, I think I
could attack the flats/ridges, but probably not get it perfectly round no
matter how I danced around the circumference to avoid irregularity...

This part I can address. Unfortunately the answer is no, it will not
do the job.

As the high spots go by, they will compress the flax, or move it out
of the way if you will. The flax will not "bounce back" as the low
spots go by, leaving a gap.

Thick of a rubber ball and a ball of packing material. Hit the rubber
ball with a hammer and it compresses, than resumes its original shape
/ Hit the ball of flax with a hammer and you have a disk with rounded
edges. Remember the "trick" of fitting too thick flax by rolling a
pipe on it to flatten?

Rick