Question About Tim Williams' Reverb Furnace

Tim,
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.
Reply to
Artemia Salina
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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 heat.
Thank you!
Tim
-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @
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Tim Williams

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