Sorry to be so long in getting back to the forum;
I thought the messages came to my email, but in
checking the site this evening, see that there
are a few that I haven't read yet! Our molds
were small (max was about 10" x 10" x 14 " high);
I burned out for about 15 hours at about 325
degrees in a gas kiln (square box, crude,
liftable steel mesh box lid with fiber-frax), 2
venturi burners. the kiln looks funky but it
works great and is easy to maintain specific
temps..... I saw a little carbon around the
cups, but not bad...One thing that may have
helped is that our forms were hollow, so there
wasn't much wax to burn out.... I had the
students make foam cores, then build up the wax
over that; we used acetone to get the foam out
ahead of time, so the wax had a pretty clear run
out.....
We cast with the crew at UNC-Asheville; there
were students and teachers from several regional
schools there,it was intense, a lot of work and a
lot of fun! We're doing it again next week in
Boone at Appy-State. Due to time, my students
are just making foam positives this time, no burn
out..... we are just learning about iron, and
obviously have a long way to go... but got some
good results and I will post a picture of my iron
deer antler soon.
thanks for the feedback,
Catherine
Catherine
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Re: burn out time for resin bonded sand molds
