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rebelrodder
10-18-2003, 08:41 PM
I recently replaced the old aluminum frame windows in my house with some nice vinyl ones. My question is this: should I save this old aluminum for a future foundry product or just take it to a recycler.

My question comes up from reading one of the past threads where someone mentioned using soda cans for a source of Al. Basically, it was decided that this was a far too dangerous prospect to pursue due to impurities and foreign liquids remaining in the cans. Would this "structural aluminum" pose a similar threat, aside from liquid issues? I have no idea what the alloy might be, which is another consideration. I had heard that some Al alloys don't cast well. Is this true?

Thanks in advance. A big pile of scrap hangs in the balance... http://bbs.homeshopmachinist.net//biggrin.gif

wierdscience
10-18-2003, 09:03 PM
Most of the storm door/window extrusions don't have much alloy to them,but you can make them into usable material by alloying it yourself.

On old alloy which is one of my favorites is one containing 92%aluminum and 8% copper,this alloys pours and machines well and was used in making aircraft engine cases for a number of years back in the 30's.

I usually cut up the scrap and shred the cans and clean off things like sand and glue and that sort of thing,then wiegh the aluminum and the copper to obtain the correct ratio,once the aluminum is melted I preheat the copper by holding it close to the furnace exhaust for a few seconds,then very carefully add the copper with tongs,in a few seconds the two metals will alloy and can be cast off into ingots,do not waste your time trying to pour castings straight from a scrap melt,you will be disapointed,lots of gas bubbles,its better to pour it off in ingots and remelt it later.

PS be sure and mark the alloy on the ingots and don't breath the fumes!

SJorgensen
10-19-2003, 11:24 PM
I agree. I think you should go ahead and make inguts. Note what you know about the metal. You will be able to tell the hardness and strength if you cast some small long pieces that you can test by breaking in your vise. Even scrap aluminum will be useful for lots of castings that don't require the strengths of an alloy. It's kind of fun and relaxing and good practice.

Spence

CCWKen
10-20-2003, 10:56 PM
As long as you're not building for NASA, another good source of aluminum for projects is the scrap yard. Also, auto wrecking yards. I watch for engine blocks that are cracked or otherwise dead. I've picked up 4-bangers for $15. Lots of aluminum for the price.