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whats d temperature needed to melt soda cans? how good r they for investment casting?

simple. i want to  melt these cola cans (and beer cans too ! ) so i can use it to cast some stuff. interested mainly in investment casting (lost wax method). need to know the temperature. precautions and possible cases of going wrong.
i have an  electronic muffle furnace. if it helps..

regards,
 Chakra


jtobako4 years ago
Melting point in technical works is the slushy, grainy point-casting takes place at about 100 degrees f higher IF all you are doing is simple, thick pieces.  Thin pieces take a higher temp because you loose heat as the metal flows threw the mold.

Cans aren't the best aluminum for casting-try to find aluminum castings and melt them for a better casting alloy.

Investment casting has different problems at different sizes-a small, thin item is going to need more pressure (longer sprew or something to push the metal into the details) and more heat than a big, fat design. 

Aluminum gets a 'skin' of oxide very easily.

Are you pouring or just letting the metal sit on top of the mold in the furnace as it heats?  www.tienchiu.com/travels/ghana/kurofofrom-lost-wax-casting/ has an example of combining the crucible and mold in one unit.

What are you using for a mold?  Plain plaster of paris doesn't hold up to well at molten metal heat.
Hi Chakra.Re popcans. you can but don't. the problem is twofold. pop cans are pure Al, and that is a proper bugger to cast right. (gas absorption). #2 is all pop/beer cans go into a dryer (commercialy) to get rid of moisture.they are held at a high temp for a long time before melting.  i've had one moisture explosion so far (20 yrs exp.) so don't go there. I go to the junk yard and pay 60cents per lb for scrap. Likewise. anything that is an extrusion (window/door frames) are nasty due to high Si content, They make a mushy casting. Any pix of your furnace? Good luck, J B B S
chakra (author)  jimbobbillysue4 years ago
i have a decent muffle furnace capable of 1100C. lined with fire bricks, and a insulated door with a asbestos gasket. not much air will pass so dont have to worry of oxidation. only when taking out the melt chances of open air burning is there...
Aluminium melts at 630 C -ish depending on the alloy. It dissolves most metals, so make sure you have a decent crucible

Steve
I've not had a problem with steel, what does molten-Al rot?
Mind, the steel would have an oxide-layer of sorts.

L
What we do is done in oxygen free conditions, the corrosion is horrible. What we have done though is used a high Cr stainless and baked it ~800C in air. The oxide layer seems to work well.

Steve
Beer-cans, bean-can, open-fire works - but that's not nice clean aluminium (or steel). The steel cans burn through in the end but you get long enough out of them.

L
1120 degrees ferinhight will be what you need