Just a note of caution:
Although we, in our field, deal with many procedures that, if not
used safely, could cause us physcial harm, curing urethane in our
studios is not a safe procedure. Lee Marshall's (designer of Bonny
Doon hydraulic presses) experience with curing urethane resulted in
some fairly severe, some temporary, some permanent and almost fatal,
Unless you are completely certain that all fumes from the process
are being vented out of your breathing space, it is not recommended
that you attempt to pour and cure urethane.
If any of you out there in the Orchid 'ether' is aware of a safe
method for dealing with urethane curing, please respond to this
message. Unless you are into Russian roulette, i.e. gambling with
your health and life, forget about saving a few bucks. Save your life
by buying your urethane already in cured form.