this is HIGHLY frustrating. You first have to MAKE enough heat to melt the aluminum. THEN you have to have “more” because things start cooling down q-u-i-c-k once out of the furnace. At THAT elevated temperature (above liquidus)? Things are happening like… your melt which is a precious commodity? Is “burning off” into aluminum oxide quite steadily.
raise the temps of the furnace more to give yourself more time? you start burning it off like lighting paper on fire, lol… aluminum cans, which is of course the most popular “thing” to melt to GET molten aluminum at home? Has got to be one of the crappiest sources of aluminum going.
you see, when you melt metal (as any self respecting bullet caster can tell you?) you have to have a big load of the source metal… you melt it, and you pick out the “crap”, and theres plenty of it. Its called “dross” and its the waste equivalent of “slag” from making steel… its a total waste product.
The dross is lighter and riding on top of your melt… and its POROUS so, its sucking up your precious commodity of melt like a sponge. You have to “flux” the molten liquid, which makes it all smooth and creamy temporarily, allowing you to mix it thoroughly… and the waste comes up top where it can be pulled off to the side withOUT sucking up metal like a sponge… and you have a very limited time window of opportunity to accomplish this.
THAT leaves the final melt of very much cleaner metal? which you can now make clean INGOTS from.
but, you still havent made diddly *&^% yet… when you have enough ingots of the right size? you can NOW get a melt going, with the clean metal… which of course is oxidizing off at the same temperatures, but, its a ton easier to flux THAT clean melt, drag off the tiny bit of dross, then you can get a nice clean “pour” into your mold.
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its basically the same procedure as making bullets at home (i am a bullet caster, i got my technique down pat) to do this with aluminum. The problem is scaling everything UP. Higher temperatures… much higher… greatly shortened working times… higher and quicker oxidation (basically your precious melt evaporating steadily).
melting pots are GONE, your working with a big furnace, and putting a little “crucible” in it, and working out of THAT. For some idea of what i am going thru? i have a a coal furnace (a big one) simply ROCKING, the size/shape/thickness of the crucible? are all fairly critical.
its all a dance, and its frustrating.
a smaller diameter crucible? heats up fast, but, it doesnt HOLD enough melt for what i want to pour.
also, to “flux”, i have to get down IN THERE into red hot molten aluminum with tools and flux. it should be obvious that the small diameter crucible that works well, is way too small to “work in”.
thinner crucible? heats up awesome, but, it burns thru in a time frame measured in “minutes”.
thicker crucible? actually nice, and, it wont burn thru quick… but, its now getting too WIDE to be any good. A whole coal furnace’s heat, on a 3 inch diameter thick walled ductile ironpipe and base? thick enough it lasts… but, only the bottom inch or two is glowing cherry red like it needs to be. the DROSS from aluminum cans? theres so MUCH of it, that it forms a thick cap on top of the small melt, and theres more dross than melt… and i havent even made the ingot yet…
cant even get a “pour off” into a fluxing container? because what little melt is under the thick layer of dross? solidifies up the sides of the pipe trying to pour. and the dross is sucking up even more of the precious melt like a sponge.
I just today, paid 31 dollars for a couple inches of thick ductile iron pipe, with a thick cap on it… i got it working okay? but… the DROSS from the cans? is so bad and so much of it, that it gummed the whole thing up, its now useless.
you cant MELT dross, its no longer aluminum… its mostly aluminum oxide, which wont melt.
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internet information? isnt all that helpful. You have these “arseholes” online, who really just want to nmake a video people will watch, simply to get their 2 dollars beer money off of the views… they dont care if it works or not, they just need views. THEY are trying to act as if you can melt aluminum with a propane torch and just play with it. Which you CAN, but… only for purposes of making a medallion or a pendant. you cant get a big melt going.
my only “success” has been when i accidentally made ingots, by a small thin crucible burning thru, and retrieving the shiny puddles and sawing them into shape for re-melting… which of course burns thru another crucible.
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a 55 gallon trash bag of clean empty beer cans? sure, it weighs a couple pounds… but, you LOSE so much of it to dross, i couldnt cast a solid 2-d maglite, lol…
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the only way i am going to get anywhere? is by buying ingots ready to go… which put me up against the MARKETPLACE. All the “arts and crafts” f*cktwits out there in internet land? THEY want to make hippie jewelry, and “americana art” (which is latin for “junk”)… they wanna cast their girlfriends NAME on a desk plaque… etc etc…
and THESE idiots have ruined the price of clean ingots online? because the little wifey that wants to play “artist” wants to cast NECKLACE PENDANTS… and thinks paying 6 dollars a POUND for aluminum ingots that aint worth 2 bucks a pound to make her life easier? its just marvy to her…
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so… what am i GONNA do? glad you asked…. quitting is not an option. My couple of small “wanna be ingots” i saved up and got one small GOOD melt fluxed and poured? worked good enough i am machining ONE small flashlight out of right now.
I have to buy online ingots cleaned and ready to melt/flux/pour for home casting?? but, i have to BUY a minimum of 100 pounds of it at once, in order to get “up above” any weight that the single mommy hippie artist could possibly want.
then, i STILL have to waste pounds at a time, figuring out exactly WHICH diameter/thickness/height of ductile iron crucible? will “work” without clogging shut useless (thown away, bye bye 30 dollars) one after the OTHER until i get just the “momma bear” crucible that “fits” my particular setup.
when you SEE it all being done in a video, and they have a “build” plans ready? Thats all tuned, by trial and error, to THEIR furnace’s heat, to their furnaces shape and size… to their timing and everything.
but… as all compared to the sheer COST of buying and shipping “3 inch stock” to my house?? so i csn literally “play” with it to get good enough to scratch machine a light? thats expensive to buy 3” stock per foot… as any machinist here can easily tell you…
i am taking it in the rear end without lube, getting myself to the point i can make stock at home to work with.
shrugs
this rabbit hole is a tad deeper than it looked on the surface, LMAO.
i also have any number of cuts and burns and blisters to show for only ONE small light i am actually cutting on right now, ha ha.
