William,
I've only boiled Madrone, because it needs it. I've followed the crowd
that advocates leaving the walls 10% of diameter and then boiling for 3
to 4 hours depending on the size of the blank. I've also left the
blank in the water until it is room temperature. Then since the advent
of alcohol soaking to assist drying I've saoked 24 hours in Denatured
alcohol and wrapped the bottom and sealed in around the top lip. Then
store it out of the sun and where air can circulate into the interior
to dry it out. Madrone usually grows a beard of mold which can be
truned away after the blank is dry. I don't have a scale or a moisture
meter, just go by feel and it is usually two to three months before I
final turn and finish. Most of the Madrone I turn is over 12" and I've
had good success with this method. For wood prone to splitting and
cracking, like fruit wood and reactionary blanks boiling can't hurt.
Good luck
Roger Dunn