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Re: Aluminum Collection for Casting Small Parts

Posted: Sun Aug 09, 2009 1:37 pm
by wammie
Uptownmaker, I have a some cans to deliver to ya. Please send me an email to let me know when would be a good time.

Re: Aluminum Collection for Casting Small Parts

Posted: Tue Aug 11, 2009 8:46 am
by wammie
wammie wrote:Uptownmaker, I have a some cans to deliver to ya. Please send me an email to let me know when would be a good time.
Actually, I'll bring the cans to you at this Wednesday's meeting.

Re: Aluminum Collection for Casting Small Parts

Posted: Tue Aug 11, 2009 7:45 pm
by darus67
Beverage cans is probably one of the worse sources of aluminum for casting.
Ideally you want to use other castings to re-melt. Things like pistons, con rods, tranny cases
are the usual sources I see recommended.

I think the purity of the beverage can ingots might be improved by re-melting them and
skimming more of the crud off.

Re: Aluminum Collection for Casting Small Parts

Posted: Fri Sep 11, 2009 5:42 pm
by bobble
Festival! Festival!
decided to have me my own backyard renaissance festival. why pay money to see others blowing glass or blacksmithing when you can do it at home for free! maybe i'd make something useful like a unicorn or a lathe.

i had acquired more cans for this melt -- the new miller light cone top cans looked promising. the metal was definitely thicker than soda cans. this time instead of pointing a hair drier underneath the make-shift foundry, i mounted two popcorn tins together and ran a pipe from the hair dryer to the lower tin. i had thought my mistakes were not directing enough air and maintaining fuel. last time i ended up with a chunk of useless aluminum.

The Setup
picture of the setup. i was going for a christmas theme. note the strategic placement of red duct tape.

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Did WWII Nazi Scientists Really Try To Build A Time Machine
i dunno... maybe... anyways, i ignited the briquettes. after a minute i switched on the air. it took awhile for the soup can crucible to start glowing. threw in some cans. kept shoving in one after the other. the new miller lite cone tops made a cool popping sound. the other cans didn't. threw more briquettes to keep the fire going. took a coat hanger to push down on the mess. saw some shiny stuff but with lots of dark crap on top. it felt spongy.

No Soup For You!
when i saw and poked the aluminum, it looked like another failure. pulled the crucible out and as i placed in on the ground it fell apart!!! arrggg!!! failure complete!!! zero for two!!! after it cooled off i peeled the can away. lots of craggy aluminum chunks. the crucible had a hole at the bottom. i suspect that the coat hanger poked though while i was pushing the aluminum around.

overall i had about a third of the soup can filled with aluminum and other crap.

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Cultural Learnings of America for Make Benefit Glorious Nation
1. prolly i need a better foundry
2. i suck at this.
3. i don't know how other people on the web do it. especially these dumbasses. i might be over thinking it.
4. i kept the soup can crucible in too long causing it to deteriorate? definitely a better crucible.

Re: Aluminum Collection for Casting Small Parts

Posted: Sun Sep 13, 2009 10:38 am
by bobble
Cleaning Up... Days Later
sunday morning i started to clean up the mess from friday. i emptied out the ash and saw a big glob of shiny stuff. i disassembled the tins and found where the aluminum went.

i'm actually relieved. it didn't make sense to me that the amount of cans i melted would amount to a 1/3 of a soup can of craggy black aluminum. not quite ingots but at least I can remelt this stuff.
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Look!!! Its a Unicorn!!!
dig the spike! these chunks have some heft to them.
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Re: Aluminum Collection for Casting Small Parts

Posted: Sun Sep 13, 2009 6:46 pm
by jtbarclay
It looks like the holes in the bottom of the first can acted like a strainer and let the good stuff fall through while keeping the icky stuff up above. You might be on to something...

Re: Aluminum Collection for Casting Small Parts

Posted: Sun Oct 11, 2009 3:29 pm
by bobble
Okay... lets try this again.

The Setup
same as before except this time i went to the institute of scandinavian surplus and picked up a new crucible - a mattlig which means stainless steel crucible. about $6.
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Not Again!!!
i filled the bottom of the popcorn tin with a single layer of charcoal. in retrospect i think this was my biggest mistake and prolly explains what happened the first and second time. ignited the charcoal and turned on the hair dryer. it took a long time ramp up the heat. eventually the walls of the crucible were glowing orange and so i started to ram one can after another into the crucible. i put more charcoals onto the fire but unfortunately dropped one in the crucible. fished it out but it was a mess. tried melting more cans but something was wrong. i thought maybe there was charcoal inside the crucble and that it was effing things up. the walls were not glowing as brightly. i started poking at the mass and it was stiff. i turned off the hair dryer and lifted the crucible out. it was a solid mass. %@# &*%@ IT!!! went inside for a minute to cool off and talk to ms. bobble.

Oh What The Hell..
went outside to clean up but then changed my mind. i had a 1/4 bag of charcoal left and threw some back into the popcorn tin. i put the crucible back on top. it sat high above the popcorn tin. i thought being that it was cold and windy that this wasn't going to work. i turned on the hair dryer. this time the fire was really roaring! almost like a blow torch. wasn't doing that before. encouraged, i put more charcoals along the side of the crucible as needed. it didn't take long for the aluminum to melt again.

I Love It When A Plan Comes Together
i was running out of charcoal. there was a bunch of crud on top. i tried to remove it but decided not to be a perfectionist and to just dump it into the mold. i believe i the crucible was filled a little more than 1/2 volume. instead of crud i was amazed to see shiny aluminum pour out. the sprue overfilled and went onto the grass - i wasn't quite prepared so i poured the remaining aluminum on top of the mold. there was some bits of charcoal in the remaining slag.

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i was pretty excited. i waited about 1/2 an hour and broke open the mold. i had low expectations coming into this. when i opened the mold i saw my creation. i couldn't believe it!!! IT WORKED ...

...well sort of!!!

The Reveal
although it may appear as a failure it exceeded my expectations!

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i molded a dakine snowboard stomp pad. all i really need is one row of spikes to glue to the tail of my alpine snowboard. i could saw off the middle row! or, i could glue that big ugly piece on the back. reason for all of this is i'm protective of my board and i'm tired of yelling at dumbasses in the lift line who ride right on top of the tail. i might retry this again and add a riser to the mold.

hey, anyone board? parlez vous bomberonline?

Lessons Learned
1. add a much deeper layer of charcoal for the bottom. more fuel on the bottom was the key.
2. start off by igniting the bottom layer first then put the crucible on top and fill the sides with charcoal as needed.
3. add a riser for the other side of the mold or maybe move the sprue to the middle of the pad.
4. have something ready to pour the remaining aluminum into for ingots

Re: Aluminum Collection for Casting Small Parts

Posted: Sun Oct 11, 2009 3:45 pm
by wammie
Good going Bobble! Thanks for the detailed report!

Re: Aluminum Collection for Casting Small Parts

Posted: Sun Oct 18, 2009 6:51 pm
by bobble
had fun last weekend i though i'd try this again.

The Setup
same configuration but had some new tins... ms. bobble got these tall tins used for olives, courtesy of seward coop.

Molding Sand
i'm using silica sand and bentonite clay. seems that bentonite isn't very common. some people will use ground up cat litter because it has some bentonite in it. fortunately i was able to find a local source - i got bentonite from minnesota clay co. in edina. i got a 25 lb box. its a powder and it is really fine... so fine that it some with a material safety datasheet with warnings about cancer. worked outside and held my breath to avoid breathing it. don't remember the exact proportions... i made small batches and just threw them into a pail when they felt right. i got the sand at home depot.

Tourettes By Proxy
my neighbor had the windows open. i heard him yelling, "efff!! EFFF!!! YOU EFFERS!!! NOOOOOooo!!!". at first i thought he was yelling at his kids then i realized the vikes were playing. i can only handle the vikes so much. go vikes.

anyways, great day to be outside! i was doing double duty -- filling the crucible with aluminum and then pausing to fill the foundry with charcoal. i was melting cans and some aluminum pieces a buddy donated. whenever the flames weren't roaring like a blow torch i'd toss in more charcoals into the foundry. the crucible would occasionally shift inside the foundry. three times i lifted the crucible out and put more charcoals at the bottom of the foundry. after the cans were all melted, i shut off the hair dryer and pulled out the crucible. it felt heavy and i was a little nervous handling it. i tried skimming off more crud with a spoon.

when i first poured the aluminum the sprue filled up quickly. initial thought was the sprue choked and that there'd be some defects. with the remaining molten aluminum i tried making ingots. first poured into an old muffin pan. i also poured some into a tin can. grass was smoldering.

Casting Of Discernible Awesomeness
after about 1/2 hour i dragged ms. bobble outside to see me open the mold. i lifted the cope all i could see was the scorched sand on the drag. YES! i flipped the cope over and the casting was alll filled in, NO DEFECTS!!! OOH RAH!!!

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the casting was still hot. picked at it with a tool to dislodge the sand. some sand is bonded to the tips of the hersey kisses which is extra fine by me. makes the points sharper and likely to gouge the hell out of someone's snowboard or skis. the bottom was flat but has a rough texture. total weight including sprue is 12 ounces.

the muffin pan had melted underneath. uhh... whoops. :roll:

i tore open the can that i poured aluminum. bobble make wheel! weighs 9 ounces. on the top of the pour, the aluminum has a rough surface like pumice. the edge and bottom are smooth. there are tiny little holes from hydrogen bubbles i guess.

High Five

here it is again. my only complain is i wish that the surface was a wee bit smoother.
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Re: Aluminum Collection for Casting Small Parts

Posted: Sun Oct 18, 2009 10:06 pm
by noise
Nice, I'll try to get your last post up on the blog and link this thread for the history.

Update: Posted