I was just at your reverb casting furnace page and had
a question regarding the use of a ladle. You didn't
mention when you skimmed the dross from the melt, but
I suspect that this was done before transferring the
charge to the ladle.
My question is, why use a ladle at all? It seems
like you could tilt the furnace to pour the charge
directly into the sprue of the mold.
I certainly like the idea of a reverb-type furnace
because it eliminates the need of an expensive
crucible, tongs, and etc.
Have you found that the rough surface of the furnace
causes metal to cling to it? How do you clean the
furnace when switching from melting aluminum to melting
bronze, let's say?
Thanks, very informative web page you have.
I skim it before pouring from the furnace. I don't preheat the ladle much
so I want to get it in and out of it as quickly as possible...
FWIW, these days I use a dab of flux on the melt. Anyone wanting to try can
grab a can of Morton Lite Salt which is half and half sodium and potassium
chloride. It's just loosely mixed, so you have to melt it in a crucible
seperately before use. After casting rock ingots :) you can add bits to the
aluminum melt and they will melt at a lower temperature than either NaCl or
KCl alone (as they are before melting). Think salt alloy.
The effect is a gray, powdery slag instead of sticky metallic junk. I once
melted about 10 pounds of random slag, fluxed it and poured off 4 pounds of
ingots plus a bunch of gray junk.
But that's off topic anyway...
I have recently, particularly with the bronze melts. The problem is it has
no spout to speak of so the sprue has to be in a certain location to be
filled, plus I can only get my smaller flasks under the frame.
Yes, I love it! :)
Not bad. Aluminum peels off easily except where stuck on (say drippings or
slag that dropped and caked on the hot areas). It leaves a thin, easily
peeled skin around the sides and a small slab in the bottom.
Turns out bronze wasn't bad either, the leftover flux gobs stick pretty well
but the metal itself is only sitting dry against the refractory.
Also, the metal shrinks more than the refractory so even if you run out of
gas (as I have once(!), the slab can still be extracted.
Unfortunately, bronze picks up a lot of gas.. I should try different things
before giving up for for the time being, I would recommend crucible melted
bronze. I also suspect you can get more heat into a crucible, since here
you only have the top surface area heating; a crucible is surrounded by
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