- I tried using a castable refractory (wet concrete consistency) in my
gingery style crucible mold but it was a complete failure. the
refractory never set up and crumbled upon removal from mold. no doubt
I used the wrong ratio of water to the mix, since this refractory was
given to me i'll have to experiment further with it. I then used a
refractory that has a more plastic consistency and rammed it into the
mold much the same as ramming green sand. The crucible was a little
difficult to remove but that was because I used a silicon spray for a
mold release and all that ramming scraped it off the walls of the
mold (my theory of course). When the crucible did come out it looked
good and was solid except the lip was a little rough because I didn't
ram hard enough at first. Set it in my $10 goodwill toaster oven (set
the oven on its end so the crucible would set right) and cooked it
overnight at 200 degrees. Removed it out this morning and it was hard
and ready to be fired in the furnace (this weekend). Looks like you
can get four or five crucibles from a 50lb box of of this type of
refractoy, cost was I think $30 for the refractory.
- Look at the BCS site for lifting tongs and pouring shanks. You should be
able to make suitable copies.
Dan in Auburn
From: firstname.lastname@example.org [mailto:email@example.com] On Behalf
Sent: Tuesday, December 04, 2007 8:02 PM
Subject: [hobbicast] crucible
Any thoughts from the group on using
SiC crucible from BCS A form #4 to be used
for melting AL and brass.
If this is good, what lifter and pouring
devices would work safely?
I have a steel crucible with lifting pins at the top
and a pouring ring on the bottom that I use two tongs
to manage. One to lift from the pins and then hook the
base ring to pour. It's awkward for larger pours.
What's a better idea for 4-6 lb AL pours?
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