Mystery Metal

H

Hardcase

New member
I've started running across this stick-on weight lately:

mystery.jpg


It's malleable like lead, but it floats like zinc and doesn't melt. What the heck is it?
 
OH, joy! Another mystery metal in the wheelweight business. I've never seen anything like that, but would love to know. Malleable like lead, floats like zinc, but won't melt. Sounds like a caster's nightmare.
 
Sounds good !!

There might be something wrong with your set-up as a 650DegF. should have take care of it. I smelt, way above that and cast as high as I can go with my pot. .... ;)

Be Safe !!!
 
Pahoo, you're right, something is wrong with the rheostat or the thermostat on the pot, but it gets the job done and I'm too lazy to fix it :p

I rationalize my laziness by figuring that if I can't get it hot enough to melt zinc, I should be able to keep myself out of trouble. My casting pot gets plenty hot, so I'm good on that side of the operation.
 
Won't fix what almost aint broke.. ..

I'm too lazy to fix it
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Mine is an old pot with just a rheostat and dial on the front. I too was having trouble with mine so I cranked it up to max, left it there and not we are getting along just fine. The Bi-metalic switch went bad and not worth fixing. Even when new, they all have their limts. I like that old thing cause it has a drop valve. ... ;)

Be Safe !!!
 
Cadmium

Cadmium has a higher luster and a blue-grey color than the metal pictured in the initial post. But the photo may not show the true color.

A good way to help identify the mystery metal is to measure one of the little ingots to determine volume in cubic centimeters, weigh it to determine mass in grams, and calculate density in grams per cubic centimeter. Cadmium 8.65 g/cc, lead 11.35 g/cc, and zinc 7.14.
 
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Metal ID

Did you try the wire cutter test? Take a pair of sidecutters (for wire) and put your mystery metal in the jaws and squeeze....if you can make a dent, it's a lead alloy. If it's too hard to dent, it's probably zinc or steel.
 
Harness Testing

Please understand that I mostly work with known pure lead. .... :)

As some of you might know, harness testers can be a bit pricey. As an alternative, I took an "automatic" center punch and lightly ground, rounded and polished the tip. I use a know pure lead sample, punch the lead and then the alloy, in question. I then compare the top of the punch or dimple, with a magnifying glass. If the top of the dimple, on the unknown piece is smaller than the lead, then it's obviously an alloy. .... ;)

Then there is the old Buckskinner trick of scratching with your thumbnail.
Another melt test, is to take a sample know lead piece and unknow alloy and lay them in the bottom of a flat pan and slowly bring it up to temp. In most cases, the lead will melt before the alloy
. I use to do this test three times but now, only need one.

Wash your hands and;
Be Safe !!!
 
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Another melt test, is to take a sample know lead piece and unknow alloy and lay them in the bottom of a flat pan and slowly bring it up to temp. In most cases, the lead will melt before the allow. I use to do this test three times but now, only need one.
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:confused: The alloy should always melt first.
 
Put a metal (steel) coat hanger on an anvil and tap it with a hammer. Flattens? If it does, it is "malleable" and then steel is malleable. Be careful with your definitions.
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I'm sure you would say the same thing if I used the word DUCTILE or even the term PLASTIC DEFORMATION.

I could say use a magnet but then that would be negated by some types of stainless steel.

So where do you want to draw the line?

[/end highjack]

Back to the subject, If you get plastic covered metal; you have steel for sure as the manufacturers of non lead wheel weights are not currently covering zinc with plastic.

Pure Zinc has a melting point of just under 790 degrees. It goes into the 8's depending on the impurities or alloying materials.
 
Zinc will react to muretic acid , just a drop ,it will dance a jig on zinc lesser on an alloyed metal of sorts no reaction on lead/tin/lino.Take normal safety steps handling the acid !!!

Not cadium ,it`s to expensive to put on wheels just to be torn/slung off .& cadium is more toxic than lead !!

Look like weights of of an import of sorts , they maybe aluminum ??

Lyman provides an adjustment on most of there furnaces , remove the knob, some have a set screw some slide on , look at the shaft is it hollow ?? if it is take a small flat bladed screwdriver & insert it it`ll engage the adjustment screw , can`t remember which way to turn it though .
 
I'm sure you would say the same thing if I used the word DUCTILE or even the term PLASTIC DEFORMATION.

I could say use a magnet but then that would be negated by some types of stainless steel.

So where do you want to draw the line?
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Malleable and ductile are Synonyms. In fact I would have a problem if you said Zinc was ductile and steel was not. They are both malleable and ductile.

Mr. Dictionary is our friend. It keeps us from perpetuating incorrect terminology if we do not have the education to know the correct terms.
 
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...Another melt test, is to take a sample know lead piece and unknow alloy and lay them in the bottom of a flat pan and slowly bring it up to temp. In most cases, the lead will melt before the alloy...
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In most cases...with the exceptions being, Bismuth, Cerrosafe, most lead/tin alloys, and some others I am probably not aware of.
 
Ductility and malleability are not always coextensive – for instance, while gold is both ductile and malleable, lead is only malleable.

Rich, Jack C. (1988). The Materials and Methods of Sculpture. Courier Dover Publications. p. 129. ISBN 0-486-25742-8.

malleable (ml--bl)
Capable of great deformation without breaking, when subject to compressive stress.

http://www.thefreedictionary.com/malleable

ductile (dktl)
1. Easily stretched without breaking or lowering in material strength.

http://www.thefreedictionary.com/ductile
 
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