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chiphead42
09-11-2006, 02:29 PM
Hello I have a question that I hope someone can answer. While poking around local scrap yard today, noticed lot of cast aluminum ingots, said to be melted down trans. cases. the size is such that I could handle one on my hor. saw & milldrill. Anybody know if this would be suitable for milling/turning fixtures, parts for my use nothing to be sold? Thanks for any help. chiphead42

torker
09-11-2006, 02:54 PM
I'd take that stuff in a heartbeat...likely 356 alu. As long as the castings look relatively clean and there isn't too much porosity....
Russ

Mike Burdick
09-11-2006, 02:56 PM
chiphead42,

Where I live the local scrap yard throws all "aluminum" into a truck and takes it to someone that melts it down into ingots for them. These ingots contain everything from beverage cans, to extrusions, to transmissions. For curiosity, I asked one of the workers there to band saw one in half for me - it had holes, bits of slag, and was generally not fit to make anything from it.

You might have them cut one for you and see what you think but in my case it was far less expensive to get a piece of known aluminum in roughly the shape I needed.

Something you might consider is making your own melting furnace. It can be made very easily to use charcoal as the fuel. That way the 'neighbors' will not complain about the smell - they'll just think you are having a BBQ. If you do your own casting, I found that the best 'raw material' to use is something that was cast in the first place. Melting things like extrusions and soda cans make casting a real pain!

topct
09-11-2006, 03:06 PM
Someone I know bought a special furnace for reclaiming aluminum from scrap and junk. It was propane fired and did a very nice job of seperating it all. Had a rotating ingot casting thing in the front that worked really well.

You then could, when cool, hold in your hand, clean scrap and junk. :D

torker
09-11-2006, 03:25 PM
Ummm...yup..Mike brings up a good point. I was thinking they where made from tranny cases exclusively.

Evan
09-11-2006, 03:30 PM
Cast aluminum has a lot of silicon in it, up to 10-15%. It will eat tools and blades.

Mcgyver
09-11-2006, 03:46 PM
Evan, even if you're just re-melting pistons or whatever? If you can re-melt pistons and get AL castings that machine well, where and why does all the SI come from? I've machined AL castings before and they were fine to work with??

Evan
09-11-2006, 04:06 PM
It all depends on the type of casting alloy. Some are fairly low silicon but some are really high. The silicon makes the aluminum flow better and makes it less brittle at high temperature.

Regardless, it may machine just fine but it will take the edge off the tools pretty quick. It also won't anodize well if at all.

chiphead42
09-11-2006, 05:02 PM
Thanks for the advice fellows. Being that I'm a curious sort I will go back tomorrow, get one & chop it up, see what it looks like. chiphead42

JPR
09-11-2006, 05:33 PM
If your interested in melting your ingots, you can build a simple furnace (http://members.optushome.com.au/terrybrown/welcome.html).

WORMgearster
09-20-2006, 01:49 PM
I would be interested if the ingots you saw at the Scrap yard had any cast numbers or symbols of identification on them???? I would think that ingot in a local scrap dealers yard would be odd... the real value to the seller would\should have been to sell back to the producer. You may have found certified ingot or toll melted ingot. Either way, it may be worth more than the scrap yard price.

As far as Silicon in cast Aluminum lets say a A356 material, "The most cast aluminum alloy", runs 6.5 - 7.6 % of weight contained and is needed for machinablity and strength. Magnesium, 0.25 - 0.45% is critical to the machinability as well. If you have "gummy" Aluminum that you are machining and your threads "pull" has they are cut, it could be that the Mg content is low.

Chiphead42... hope you get good chips from your Aluminum

WORMgearster
09-20-2006, 02:00 PM
I would be interested if the ingots you saw at the Scrap yard had any cast numbers or symbols of identification on them???? I would think that ingot in a local scrap dealers yard would be odd... the real value to the seller would\should have been to sell back to the producer. You may have found certified ingot or toll melted ingot. Either way, it may be worth more than the scrap yard price.

As far as Silicon in cast Aluminum lets say a A356 material, "The most cast aluminum alloy", runs 6.5 - 7.6 % of weight contained and is needed for machinablity and strength. Magnesium, 0.25 - 0.45% is critical to the machinability as well. If you have "gummy" Aluminum that you are machining and your threads "pull" has they are cut, it could be that the Mg content is low.

Chiphead42... hope you get good chips from your Aluminum

chiphead42
09-20-2006, 04:16 PM
Hello There are no numbers on the ingots. Scrap man says he gets them from 4 different sources. Apparently small operators. Don't know why they
sell to him instead of end user. All 4 are long way from him nearest 70-80 mi.
I contacted 1 guy 70 mi. from me, he only pours occasionly, when he has enough scrap. said he will pour a mold for me. I have made several cuts on the 1 ingot that I bought, has slag & porosity in center, will be about 50%
usable. Don't know if its from the guy I talked to. This means higher cost & more work to get it. not as good deal as I thought. It cuts & machines good, will be ok for what I will do with it. If I have him pour for me I will be sure he keeps it clean. Thanks for the help. chiphead42