Increasing ingot yield from aluminum scrap

[@alexandersearles9273]

You sir, are a hero to me. Regular guy, creating a community, engaging with it to collect feedback, crowdsourcing and experimenting with solutions... this is how individuals can change the world outside of traditional paths our society has funneled people in the past. No notes, 100% thumbs up, you matter and you and people like you are a constant source of inspiration that lifts me in a world filled with wicked problems that we must overcome.

[@swdweeb]

No sir, you are the hero. I had a crappy day at work yesterday and when I read your comment last night my spirits were immediately lifted. Thank you!

[@whiskeyelement8802]

Thank you for these 2 videos... answered questions I could not find answers for

[@swdweeb]

Thank you for letting me know. I appreciate the feedback and I'm glad I gave you some info you didn't have

[@boelwerkr]

The pattern on the top are from crystallization of an aluminum alloy with an slightly higher melting point than pure aluminum. Pure aluminum can also create a very fine crystallization pattern. Things like that are the risks when you use aluminum from unknown sources. For low strength stuff it is good enough but can be hard to machine because of varying hardness.

[@swdweeb]

That is probably exactly what it is. And as you point out that is what you get when you melt unknown sources. Thanks

[@jamysmith7891]

Swarf is probably a machine alloy like 6061, mixing melting or who knows about the crystals A puddle effectively provides an oxygen free environment to melt high surface area scrap

[@swdweeb]

Could be, I ended up giving away buckets full of the stuff. It just wasn't worth the effort. You're right, a puddle helps but the swarf is a pain no matter what.

[@stamasd8500]

Thank you for reminding me I need to have lunch. Good result. Believe it or not, I would actually advise you to use even MORE flux, and add most of it right at the beginning. As for the pattern on top of your ingots, don't sweat it too much. I got something similar on top of a few of my ingots, and those were remelted from 100% cast aluminum.

[@swdweeb]

Man I'm glad I could help. It's important not to forget food :-D

[@GMCLabs]

I bet that puddle really helped. Just putting a bunch of chips in without any molten aluminum, has alot of surface area and it just forms a bunch of oxide. When you submerge the chips in the molten aluminum,it protects the chips from air so they melt before they have a chance to oxidize.

[@swdweeb]

I think the puddle and immersion made all the difference in the world

[@Bigjobs]

I'm really liking your scientific approach to how you're doing this. This is going to be a bit of a long one, because this is the first video I've seen of yours. Sorry about that. When I started melting things I wanted to know how much I could get out of beer cans. I saved them. I had neighbours save them. I had family save them. I squashed them. I still ended up with about 100 bin bags full of them. I had so much that the neighbours complained that I was bringing mice to the houses (it coincided with my now wife moving in with 2 cats). So I started melting them. It turned out I was on a fools errand with them, as there is little to no ali in them, and the ali that was in them was crap for what we want them for. There are a few reasons for this. Ali cans are 11 thou thick. Included in this is a layer of varnish inside and out. Add to that the oxide layer and there's little to no ali available to harvest. Ali oxide melts at 2000C. We aren't melting it in our home forges unless we make an electric arc furnace. Another point. What ali is worth melting. Of all the types of ali, for us it comes down to 2 classifications. Alloyed with zinc or magnesium. Zinc is by far superior for us. It's what is generally used in castings. I'm really lucky that I have both a car scrap yard, and a metal scrap yard in very close proximity to me, and that they both let me buy stuff off them for cash. I've melted all kinds of scrap from both places. I've found that by far teh best ali for casting is from alloy wheels. As I said, I'm really lucky taht I can pick them up for a tenner a wheel, but i've had good results with engine parts taht were cast as well (gear box housings, alternator parts etc) And finally. If your utensils are cold, When you put them in the melt the molten metal cools down around then and sticks to them and gains more the more you use it giving you a huge blob by the end. For me, using stainless steel tools (i use a big perforated stainless steel serving spoon) lets you put the spoon in the melt till the spoon gets to the same temp as the melt. This means that the melt doesn't cool and stick to your tools. I was advised against using a steel crucible (and tools) as the iron can leach into the melt and cause hard pockets which makes machining very dificult. LIke I said, I'm a new subscriber, and am really enjoying your channel. I hope to enjoy your journey along with you.

[@swdweeb]

Good info and thanks. I've heard the same advice about alloy wheels multiple times. Unfortunately I haven't found a place around here to buy them for anywhere near as cheap as you mention. The best I've found is $2 a pound for scrap aluminum and most of it is extrusion not cast. Olfoundryman and smallcnclathes were trying to tell me to use better aluminum for casting some time ago. perhaps I should listen ;-) I've been thinking of getting a stainless spoon as you mention, just have to think about it at the right time.

[@Bigjobs]

I watch Olfoundryman obsessively. He does it for a living, so we can't argue with him from a hobbyist point of view. As for the spoon, being from the UK most of the places I would get mine aren't available to you. I looked on amazon.com and found this www.amazon.com/RSVP-Montys-Slotted-Stainless-Serving/dp/B00K2ZP2M4/ref=sr_1_6?ie=UTF8&qid=1526675894&sr=8-6&keywords=slotted+spoon+stainless+steel It's a slotted spoon if you would like to find one for yourself.

[@swdweeb]

Yes I listen to martin, but usually only after he has had to resort to strong language in an email. ;-) He's a great guy and I've learned a lot from him. Regarding the spoon, thanks. However as a hard-headed hobbyist, I prefer to spend less money on something that will turn out to be not suitable before I buy the right thing. ;-)

[@Bigjobs]

He's australian. THey only swear at friends :D

[@swdweeb]

He must absolutely love me then :-D

[@PaulsGarage]

gotta admit, i had to rewind to see what changed during the continuity test. I failed.

[@swdweeb]

Probably from all of that rust in your eyes from the hood ;-)

[@gavsgarage22]

PAUL, more casting videos every time you cast please! me and my girlfriend love watching both you and swdweeb!

[@BillyDocWalker]

I compress my swarf into very compact cyclinders and the years great

[@swdweeb]

I tried to compress it, even built a press and I couldn’t get it to hold together. I’d like to figure out a decent flux and a way to fed it into the crucible. I’ve got lots I can melt but have been holding off

[@alexwalker8422]

Top the load of swarf with charcoal powder, you could literally get that by using flour on top, that should completely cut off all oxygen entirely to the swarf. Edit: You might want a gravel of charcoal, powdered is gonna blow away.

[@swdweeb]

I've abandoned melting stuff like swarf. It's not worth the propane to try and get something usable out of it. The stuff is mostly aluminum oxide and creates lousy castings.

[@DKW-Biker]

Cool ingot pouring buddy. Can't wait for your next video. Like and sub.

[@swdweeb]

Thanks for the sub!

[@DKW-Biker]

@@swdweeb Have a great week buddy.

[@Uncle_Bucks_Forge]

Cool that was a fantastic increase in years. Wish you would have done a close up on that salt. Mortally sure what it is.

[@swdweeb]

"Increase in years" Ponce de Leon would have been proud ;-) The salt is Morton's Lite Salt. You can buy it in any grocery store.

[@Uncle_Bucks_Forge]

That was yield. LOL

[@darrendaz6969]

Hi bud, I like you smelting videos they great. One question is what size of crucible do you use? A5-6? Cheers

[@swdweeb]

Thank you Darren. That means a lot to me today. ;-) Been reading stuff from people that think differently than you do. I use a 6KG crucible. This one to be specific I use a #4-6 Kg ProCast Foundry Clay Graphite Crucible from PMC Supplies LLC. Bought it on Amazon FWIW, smelting is the process of extracting metal from ore, what I do is smelting without the "s" :-D Thanks again for the comment

[@darrendaz6969]

Thank you brother. Your Crucible looked like a good size to handle big enough to make some good castings but not so large to be too heavy. I think the weight 6kg is copper weight or brass. I’m guessing aluminium is more like 2kg? Putting finishing touches to my gas kiln the now. Can’t weight to melt some stuff! Also looking at using oil sand to cast as from my research it gives better detail then green sand, though a bit smokey. Thanks for reply, so many don’t these days. To famous lol ;-)

[@swdweeb]

Yeah, it always annoys me when people don't respond, so I try to. I think you're correct in the weight. I don't know how much the aluminium weighs, but it is noticeably lighter than the bronze. I was told to buy my crucible first and then build my furnace around it. Of course I didn't and my crucible is right on the hairy edge of being too large. So far it has been a perfect size for me. If the diameter was 5 or 6 mm shorter across the top it would be perfect ;-)

[@treym8561]

You could also use potassium nitrate

[@dibblethwaite]

If you want to make a bomb, yes.

[@Mike-sv2nu]

I wonder how much of the new weight is sodium.

[@swdweeb]

Its been so long ago that I posted that video I have no idea what I did in it. I recall making a puddle and dunking to the meta into it to increase the yield. Surely I didn't dump lite salt into it. That is the biggest lie out there. But even if I did, it's potassium chloride and not sodium chloride.

[@chriskustra507]

I use boric acid for my flux, thats what I've seen a lot of other people use whether smelting or blacksmithing. You can get it from the laundry aisle at walmart in a box of Borax.

[@swdweeb]

Yeah, I've seen it. I suppose it's worth a try. It's cheap

[@stamasd8500]

Please don't use boric acid for aluminum. It's not a strong acid, but still reacts with aluminum and increase the amount of dross and aluminum loss. Boric acid is best left for much less reactive metals like copper.

[@chriskustra507]

stamasd ok so use boric acid for copper and use salt for aluminum? Does it matter what type of salt whether regular table salt, sea salt, or light salt like in the video?

[@stamasd8500]

I use a 1:1 molar mix of sodium chloride (table salt) and potassium chloride (water softener from hardware store). That's 58g sodium chloride to 75g potassium chloride (or approx 2oz of the first and 2.5oz of the second). The advantage of this mix ratio is that they form an eutectic so the melting point of the mix is as low as it can be. Sodium chloride melts at about 800 degrees C and potassium chloride at 750, but the mix melts at about 620 degrees C which is in fact lower than the melting point of aluminum.

[@chriskustra507]

stamasd thank you for the info, I'll be sure to try that out next time I use my foundry. I have one more question, is it possible to reshape a broken clay graphite crucible? The first one I bought I forgot to dry and temper so, of course, it shattered right away. I gathered all the broken pieces and figured since it contains all the same mixture from when it was made, maybe I can grind it all down to powder, stir in a little water to hold together, put in a cup shaped mold, compress it tight with some c-claps, and bake it for a while. Do you think that could possibly work?

[@mindofmadness5593]

Just FWIW [[not much]]. My main source of Al is cans at this point. I use the mortons too. I put one of my ingots in and melt it then push the cans in as fast as possible to minimize oxidation. Before the pour with the flame still on I add in a decent amount [[tablespoon I suppose]] of mortons and stir it in quickly. My dross comes out black and crmubly with no or little AL in it. If I forget the mortons I get big chunks of drossy AL to throw away. Oh and for gits and shiggles-I sometimes put the pans of frozen lasgne in there after we eat the stuff for the Al-it smokes, smells like scorched lasgne but it also gives me the same dross as Mortons-black and crumbly. BTW Paul sent me so where's my beer? :D

[@swdweeb]

Wait, he told you there would be beer??? I'll send you his address, you can pick it up at his house :-D I actually melted quite a few cans for the sprue former I sent Paul. Like you, I immersed them pretty quickly to minimize the dross formation. I haven't noticed the mortons thing work but I can always try it again. I'm in the middle of rebuilding my furnace so it may be two weeks before I get another casting in.

[@mindofmadness5593]

His vid about your Sprue thingy is why I came over. I'm building my second furnace using more expensive items so it will, hopefully, allow me to melt copper and silver for some jewelry projects I've come up with inside of my twisted brain. First is sand.plaster, a year old and still functions but small, heavy and no way to move it around when it is hot [[I also do antbed castings]]. Anyway, I'm posting outside Denver at the Days Inn-Paul said YOU had the beer and gave me your address! See you in a few hours! :D

[@swdweeb]

Doh... sorry I missed you, I must have been asleep when you got here. Did you have any wind where you were last night? ;-) The best, and lightest, part of the furnace I built was lining it with fire brick. I added a coating of refractory mortar to that that didn't turn our so well. That's what I'm dealing with now. The lining started to crumble after a several uses. If you can incorporate fire brick in your furnace design, I highly recommend it.

[@mindofmadness5593]

Only wind I noticed was after eating at that crappy Mexican place I found in an Alley... I'm going with Rockwool on this one, place called Hard Luck Forge sells kits with everything needed and they are cost effective, being on disabilty I have to count my pennies but, even this new one being a full-sozed propane tank versus the pint-sized Helium tank I used before, I can tell it is going to be 20# lighter and the handles I added allow me to move it.

[@swdweeb]

;-)

[@omm7763]

What you have done is called bath smelting. On average this is about 25 to 30% efficiency on fuel alone. There is another 18 to 25% Time savings on the melt with a 25 to 30% reduction on oxidation. The end result is you should have almost 60% more production with 50% less fuel and time.

[@swdweeb]

Of course I quit melting cans just because they're junk and full of oxides ;-)

[@omm7763]

@@swdweeb I agree, but so many followers love to see something cool made from nothing....

[@swdweeb]

@@omm7763 Let's face it , so many followers simply love to see molten metal being poured from a crucible. I doubt that most give a rip about what the actual resultant object is, hence the popularity of casting ingots.

[@smallcnclathes]

Hi Perry Do you mind if I offer no advice at all? I seem to missing the gene that makes me want to melt metal and make it into something. Having access to good castings without raising a sweat may also contribute to my lack of desire to cast things. So, as a non casting person, I just had to say how much I enjoy your zany videos, loved the whoops with the swarf, your face was a picture of whoops? I have had a busy week, would you like another 44 of aluminium swarf? I can assure you it is alloy 2011 so you know exactly what you were working with!

[@swdweeb]

Hi Nigel, that's only because you have really cool machines to play with. Or, it's quite possible you've matured past playing with fire. ;-) Gotta have some fun with the videos. If I didn't, they'd look like that other guy's videos. You know the one, he lives a short distance from you. ;-) Somehow I think I could buy gold plated 2011 cheaper than shipping yours halfway around the world. You didn't turn that sprue former that I got in the mail did you?

[@smallcnclathes]

That was all courtesy of Martin.

[@swdweeb]

hopefully I get to use it tonight.

[@smallcnclathes]

I look forward to that video, with the sprue filling nicely and staying that way until the metal comes up the feeder. So sorry that almost sounds like advice and I can't do that, never having gone near a crucible!

[@chevydmax04]

wrap your salt into aluminum foil and drop it in that way, much easier

[@swdweeb]

Dropping salt into aluminum is pointless. It does absolutely nothing except add more crap to the mix. It isn’t a flux, it isn’t a degasser, and it doesn’t clean the metal.

[@tech-u-train8003]

Where did you get your crucible tongs from?

[@edwardervin879]

What the bleep is swarf?

[@swdweeb]

Swarf is what comes off aluminum when it machined in a mill or a lathe. Essentially the chips, shavings or turnings. Aluminum is highly corrosive and oxidizes as soon as it is is exposed to air. Swarf is then essentially aluminum oxide which is not good for melting. I still have a huge barrel of this stuff that I need to dispose of.

[@jacobmilgromiii7729]

Helpful, ty

[@swdweeb]

Glad it helped

[@Lawnmowerman02346]

A lot of guys say to use lite salt for flux and washing soda for degassing . All my melts are small , I use half of a propane cylinder for a crucible . I'm not sure if it makes a difference . Check out ( luckygen1001 ) he gets out the science book and looks up the chemistry . ( myfordboy ) has a video on what aluminium to use and he has used the salt and soda for flux an degassing . Have you given any more thought to making castings with lettering ?

[@swdweeb]

To be honest, I havent had a lot of time to think about the the lettering. I'm going to try and cast something again tonight that has a debossed (learned a new word yesterday from a commenter) pattern it it. I'm a few hours away from getting out there but I've already got my fingers crossed.

[@Lawnmowerman02346]

I fix lawnmowers so I have more cast aluminium than I do time but the whole idea was to make model engines . I did make one good one , even put up a short video but that"s it . Time and cold set in too quickly .

[@stamasd8500]

Either my torch/furnace is really efficient or there is something else that I'm missing. With one 20lbs tank of propane I have done 2 aluminum melts, a copper melt, a mixed salt melt (to make flux), an aluminum bronze melt, a tin bronze melt, an antimonial copper melt and a mixed antimony/tin bronze melt. And I still have propane in the tank for at least one more run. Each batch was at least 1 pound, using #3 crucibles.

[@ronyerke9250]

Bib! Disappearing compressor. Well done, Harry. Dude, get a metal scoop or something to add the swarf with. SMH. Pattern is crystalization, don't worry about it. Your crucible will last longer if you let it cool off INSIDE the furnace. Whoo! Whoo! The train of thought has left the station.

[@swdweeb]

Oh Ron, so many comments. There ought to be a rule, one comment per..er..comment. ;-) I have a metal scoop, but it's too big and it dumps swarf all over the outside of the crucible. Well, ok, I dump it all over the place but its the scoops fault. I think the better action is to just get rid of the swarf, it's kind of a pain to deal with. My crucible is probably nearing the end of it's life anyway. I think this is the first time I've not let it cool slowly within the furnace.

[@swdweeb]

Oh, and bibs are for babies. Real men wear their food like a badge of honor ;-)

[@ronyerke9250]

Bibs are for babies? Have you ever been to Red Lobster or a nursing facility? Smaller scoop, or just don't fill it so full. That flaming paper thing was a stunt, right? (I hope) Maybe you can compact the swarf. Funnel it into a pipe and ram it down. It might not work, but it might. Swarf pucks!

[@swdweeb]

I've been to the dead lobster, but its been years. The wife got sick there and we've never been back. I've tried filling a pipe with the swarf. You can't pack it, it is to hard to get it out once you've done that. I did make a smaller scoop... out of metal... that I was able to use for the bulk of the fillings. I'll never let on about the paper ;-)

[@ronyerke9250]

How hard can it be to get the swarf out? Just lift the pipe's end up off the floor and ram again. How much did you try to pack in there? I was expecting the pucks would crumble easily though. The kind of pipe might make a difference, too. Automotive exhaust pipe is smoother inside than plumbing pipe, and swarf might imbed into plastic. Low grade pipes tend to have a raised weld inside too, but at least that runs longitudinally.

[@massimilianoilardi2749]

ciao ti chiedo una domanda 900 grammi di rame fuso e 100 grammi di alluminio diventa bronzo ma oro24 carati quanto si vende al kg

[@swdweeb]

hello I ask you a question 900 grams of melted copper and 100 grams of aluminum becomes bronze but 24 carat gold as you sell per kg Ciao Massimiliano. Non capisco la tua domanda. Stai chiedendo perché a volte viene usato kilo ea volte non lo è? Hello Massimiliano. I do not understand your question. Are you asking why sometimes kilo is used and sometimes it is not?

[@nowayjerk8064]

i dident see you lick any of the bits you used in the vid try that next time . thanks for sharing

[@swdweeb]

Lick any of the bits???

[@nowayjerk8064]

yea well pre lick the tools for science reasons and luck

[@massimilianoilardi2749]

buongiorno ma che valore ha alluminio in lingotti

[@swdweeb]

Ha molti valori. È più facile da memorizzare. I lingotti si sciolgono con molto meno scorie e per questo posso misurarlo con maggiore precisione quando realizzo cose come il bronzo

[@WaltSorensen]

the geometric shape is the metal dendrites from the metal solidification. Small possibility you're seeing some alloy desegregation. Here is a bad video that will show what's going on while the metal solidifies. kzbin.info/www/bejne/fWbdan6ho6uSqZo

[@WaltSorensen]

here is another one kzbin.info/www/bejne/q3iWZneVmtqAY5I

[@swdweeb]

:-) you'll have to excuse me Walt. It's getting late here and I'm tired. I'll watch them in the morning. As always, thanks

[@n8hfi]

The salt is a cover flux. It melts and forms a glassy layer that floats on the molten aluminum and prevents oxidation. This layer also adheres to other contaminants that float, making them easier to skim. The reason for using the NaCl/KCl mixture is that it's eutectic. Both NaCl and KCl,, in their pure form, melt at a higher temperature than Al, so are unsuitable as cover flux by themselves. But an alloy of the two is eutectic and melts at a lower temperature than either constituent by itself (like Sn/Pb or Al/Si). A roughly 50/50 mix will melt at about the same temperature as Al. Ideally, you should melt them together to make a proper alloy before using them as a flux, but there's a lot of anecdotal evidence (including my own experiments) the "lite salt" seems to melt okay, even if it's technically a mixture rather than an alloy. You need to add enough to make keep a nice layer on top your melt throughout the melting process, until you skim it off. You don't need to add more with each addition of metal, unless you accumulate so much dross you need to skim it. The proper amount depends on the exposed surface area of the melt, i.e. the diameter of the crucible. I don't think you used nearly enough. Try a couple of ounces of flux, added with the initial charge of metal, and you shouldn't need to add more until you're ready to skim and pour. Borax, aka washing soda (NOT boric acid) is also a good cover flux, in my experience, and cheaper than the lite salt.

[@stamasd8500]

Agree on the eutectic, but washing soda is not borax. Washing soda is sodium carbonate which is not a good flux. Borax is a good flux, but it's not washing soda.

[@n8hfi]

Oops, you're right. I checked again, my box says "detergent booster", not washing soda. I wasn't remembering the label correctly.

[@swdweeb]

Great information. Thank you for taking the time to write it all up. I'll add more to the initial charge next time and see how things go.

[@BrianDaleNeeley]

Somehow, your output (499 g ingot + 175 g dross (674 g)) exceeded your input (184 g puddle Al + 450 g swarf (634 g)) by 40 grams! I suppose it's possible you added 40 g of flux, but if you do more experiments such as this, I would suggest a few containers of pre-weighed flux for use as needed. As for the clump of Aluminum that formed on your stir rod, you could possibly set it on the foundry, with the end over the exhaust. The exhaust should melt the blob off the end, and allow it to fall back into the crucible. It may also make the other end too hot to handle, so be careful if you try my suggestion.

[@swdweeb]

Maybe I defied the laws of physics and created matter from nothing. Did you ever think of that? ;-D Great catch. I assume I either weighed something wrong or wrote a wrong number down. Unfortunately I can't go back and check as the dross went out in the trash and the ingots were remelted into my latest project. Thanks for letting me know

[@mikealman9259]

I had to stop watching as soon as you tried pouring the swarf into a red hot furnace using A PIECE OF PAPER !!! REALLY!!! SMH LOL

[@swdweeb]

Yeah, I’ve done some dumb things. In my defense it worked for Tim the tool man Taylor

[@massimilianoilardi2749]

ciao tu ai fuso kg di rame e 100 grammi di alluminio per diventare oro 24 carati giusto

[@swdweeb]

ciao amico, si e vero