Ecnerwal wrote:
snip

My chains develop a "handedness" drift over time (it's difficult
to file each tooth the same when half of them point the other direction
- the left and right hands do not file the same, nor does the right hand
when asked to go backwards - same strokes and trying to use the same
pressure notwithstanding). A jigged grind job clears this right up,
which means it's more consistent than I can manage with a file.

In my case I file from the side of the bar with the handle of the saw
towards me, my chain(s) has 15 cutters on a side so when I have done 15
teeth on one side I change sides and do the other 15 teeth...the same
number of strokes.
Having done that, I still at times need to take a lot off due to hitting
a rock etc. and it is better to hold it by the bar in a vice, I even
have a removable vice I mount on the truck for times like that.
But when I'm with the skidder say 40 acres back in the woods it is nice
to have an extra loop along too.
On a related subject:
I'm getting old and a little worn out from traipsin through the brush
so I don't wear chaps, head gear, and definately no ear protection. I
need to hear the cracking sound things make when they fall unexpected or
someone trying to get my attention, and chaps for me just make it harder
to get around, and unsafe.
But that's just me....;0)
granpaw