aluminum

[marvinthemartian]

does anyone have any ideas about casting aluminum? you know, melting it and pouring it into a mould? i don't have any problems melting the aluminum, i just don't know what material to use for the mould.

[NitroJunky]

i took a class in high school we made molds out of this black sand its an oil base stuff i cant rember what its real name is but it was like dirt u can mold it. first we made a flat brick of this sand and then you carve the rivers where the metal will flow and you can imprint something into the sand or carv your own desighn. alumium melts at a low tempature you might be able to melt it with a torch but you have to get it hotter or it will freeze before its done getting pored in the mold

[weasel]

And dont you add sulfer to it to get out the impurities? I took the same class in metal shop, almost 10 years ago! Cast alum. is brittle tho.

[clancy]

I agree it is very brittle and not suitable for parts. You need to use billet al and turn it down to your part spec. This is where the cost comes in. :( :(

[outsider]

I think the strenght in aluminum comes from machined parts, bot poured cast parts like you can do with iron. Like it's already been said, it becomes very brittle.

[Rc1oGtMaN]

Cast iron would be really really heavy. My neighbor and I make fishing weights with liquid steel, and the molds are made from lead.

Mark O.

[NitroJunky]

to get teh sludge out thats what i think they called it. it would float to the top and you can take it out with this big spoon. i know are MTT class teacher verry well he was suppose to make me a chassis but i never got around to giving him the chassis.

[Clayton]

methaneman, Many companies cast their parts then machined to a nice finish and to meet tolerences..

[clancy]

I agree with you clayton, however my understanding is like you said tolerances. I believe they have the testing equipment to manufacture to iso standards. In most cases the average do it yourselfer does not have these testing methods available to them. Also Billet al is an alloy that has a certain amount of other raw materials mixed in for good measure to create the strength we enjoy. Billet is a hot worked semifinished product suitable for rolling, forging or extruding. The ASTM provides standards for this testing. I am not saying your regular joe sixpack cannot do this I am just saying why when you can buy a finished product relatively cheaply. Anyway, please correct me if I have gone astray.
Regards,
Methaneman :confused:

[Clayton]

I agree with you completely.