I use to loosely mount between centres and by trial and error find a
reasonable balance by adjusting the tailstock centre's position until
the piece would stay at rest in any position. Fiddley and time
consuming but it works. Adding weight to the light side is OK but as
others have pointed out, you have to make adjustments as you turn.
Now I have a re-built wood pile and all the pieces are wax sealed and
stood on end. Balance problems are now very rare and minor. Mind you,
having a dial in VSD that will allow single digit rpm certainly helps.
The new stacking also appears to eliminate a lot of checking problems.

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