Telling die-cast from aliuminum?

Die-cast = zinc, presumably??
Certainly cain't use magnets, eh? Chemical test? Grinder? Melt point -- not so easy, really, unless you can
sort of ball-park it with O/A....
And is die-cast zinc relatively pure zinc? An alloy?
--
EA



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Diecast metal can be a variety of things, including aluminum, magnesium, or brass. Zinc alloys are the most common.
There are simple reagent tests and test kits available to distinguish the two. But in most cases you should be able to tell by the part's density. The density of zinc is almost the same as that of iron or steel -- three times as great as aluminum.
--
Ed Huntress




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"Ed Huntress" <> wrote in message >

Here's a good story: A couple of months ago a guy showed up with a handlebar bracket for an antique chain saw that was cracked through the bar hole. It felt light as a feather. Can I weld it? Sure, it's magnesium. Oh? Your competition says it is cheap assed die-cast and can't be welded! Well, I'm sure it is mg. and yes I'lll fix it. If this were die-cast it would fell heavy to me and its light.
Got it cleaned up and prepped for weld and jigged up nice. Now, how will it act? It was by far, and I mean easy, the easiest thing I've ever welded! Easy full penny with no problem. Had to watch the temp or it would catch fire so I let it cool often. If you try this, watch for the base metal 'slumping' and stop immediately! This was a true quicky of a job and was so much fun I didn't even charge him. Gave him the mg dust in a folded paper and told him to give it to my competition at the local bar there, where they smoke. ;>)} phil k.
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That's interesting. I've never welded magnesium, but I've read that it's very easy -- if you're careful and know what you're doing.
The Brits used a lot of it in their racecars (and their mag-based Elektron alloy), years ago when the building operations typically were a few guys working in a dank garage. They welded a lot of it.
--
Ed Huntress



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We use a lot of diecast aluminum and magnesium. Just looking at the raw castings they look pretty much the same. When you pick one up you notice the difference. We machine the aluminum, we farm out the magnesium machining for safety reasons.
I wish we did work with zinc alloys like zamak, that can be cast at low temperatures near that of lead.
Wes     -- "Additionally as a security officer, I carry a gun to protect government officials but my life isn't worth protecting at home in their eyes." Dick Anthony Heller
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wrote:

Do you do your own diecasting, or is that jobbed out?
One of my first field trips at _AM_ was to a diecaster. One of the other editors told me I'd think I just gotten a look at the inside of hell. He was right. <g>
--
Ed Huntress



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Wes wrote:

Where are you at geographically? I'm in Whittier, and the shop where I sit would be happy to machine some magnesium for you. The chips are funner than a rat to play with! ;-)
Cheers! Rich
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On Sun, 29 May 2011 20:38:13 -0400, "Existential Angst"

===============http://www.eazall.com/diecastalloys.aspx
http://en.wikipedia.org/wiki/Die_casting
http://en.wikipedia.org/wiki/Zamak
http://www.crecocast.com/selecting-the-proper-alloy.htm
http://www.diecasting.org/dce/issues/0311/31136.pdf
http://www.tcdcinc.com/media/2009_NADCA_Alloy_Data.pdf
and a bunch more on google
-- Unka George (George McDuffee) .............................. The past is a foreign country; they do things differently there. L. P. Hartley (1895-1972), British author. The Go-Between, Prologue (1953).
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On Sun, 29 May 2011 20:38:13 -0400, "Existential Angst"
Aluminum is also die-cast quite commonly.

Copper sulphate solution will turn zinc and zinc alloys black, won't affect aluminum.

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