Hi Arch

I seem to recall a post and picture of someone trying to make a dynamic
balancer.

If I recall right, he had a a pipe bolted to the headstock vertical and
above, there was a weight that could be raised/lowered to find the best
position to lower the "shakes".

I don't recall how successful it was, also I have no idea as to the
forces involved, or if the device could increase the shake/shudder and
make things worse under certain conditions.

I know counter rotating shafts are used to minimize engine vibrations,
but I have more questions than answers on that.

My way of dealing with the unbalanced blanks has been adding weight to
the lighter side, last time the large 24" willow burl that I did was
screwed to a large MDF platter and weights bolted to the platter, it
worked just fine.

Have fun and take care
Leo Van Der Loo