Bob Engelhardt wrote:
James Waldby wrote: [on using pressure during resin casting] ... I think
the main intent is to more-completely fill the mold. ...

If the mold is completely within the pressure vessel the pressure will
have no effect on filling the mold.

True - or mostly true, anyway. I was thinking of a pressure vessel of
my cousin's design that contains a bladder inside it to push on a form,
and of vacuum bagging, which uses atmospheric pressure (but no vessel)
to press things together. I think you are right that the usual pressure
vessels for casting are just for suppressing bubbles.
-jiw