The proper bench height is a few inches below your bent elbow
when standing.  I have noticed that the majority of benches are
too low and that the standard height is ridiculously low.  Blocks
under the legs are often helpful.  An adjustable height bench is
great.  I have a number of different height benches for different
size projects.

Other points often neglected is rubber mats at each location where
you will be standing for long periods and comfortable shoes with good
support.  I have not found back braces to be particularly helpful,
but back exercises do help.

Bob Yorburg
Amusement Carvers of America