Testing for Zinc with Lysol Toilet Cleaner

[justindad]

Smelting the last 4lb batch out of 35 lb of soft stick-on wheel weights, and I found a half melted weight. Seemed like it should’ve been melted, so I pulled it out suspecting it was zinc. The top surface of the clean melt had a skin that looked sort of dendritic like my round nose ammo does in 92-6-2 alloy. The lead was in a cast iron skillet, which I poured into my Lyman ingot mold. Unlike the other pours, and skin of metal stayed with the pan. The cooled ingots have that dendrite look as well. The smelting of wheel weights took place over a camp fire, and I cleaned off the dross over a Coleman stove. A better setup would be nice, but I go for free when I am tinkering for the first time.
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I poured Lysol toilet bowl cleaner on the ingots, which in 9.5% HCl. The blue Linda turned white where it made direct contact with the ingot, but I would not say I saw fizz. The white could be on account of the cleaner being 5+ years old. After I washed the cleaner away, there was no etching to indicate a reaction occurred on the surface of the ingot.
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Is it likely I have some zinc in these four ingots, or is it more likely the lead was not as hot as I thought it was?

[Winger Ed.]

My guess is you found a presence of Zinc.

A stronger solution of HCL would confirm it though.
Another quickie test for Zinc would be to do your test on a known Zinc wheel weight.
Then watch how it reacts.

[Silvercreek Farmer]

I use a scratch test to test for zinc. Scratch the suspect weight against concrete vs a known lead weight. They feel completely different. The zinc will scratch almost like steel and the lead feels more like a hard crayon. Even if you got a bit of zinc in your alloy, you might be alright as long as it still flows and doesn’t clump up like oatmeal.

[Rickf1985]

If you are talking about a half of a zinc stick on that would be so small of an amount that even if that tiny bit did melt in it would not make any difference at all. Far too much is made about zinc in your lead. You can have some zinc and not have any issues at all. stick on wheel weights seldom weigh more than 1/4 oz. per section so in a 4 lb. batch you have next to nothing.

[bangerjim]

Up to 5% Zn will not "ruin" you re-melt. I have done extensive testing with forced contaminations of Zn and 5% or less makes no difference! (maybe slightly lighter booilit but you probably not even notice the difference.)


If you are worried about Zn contamination, just watch your pot temps and keep a tight control on it below the liquidous temp of Zn. Then all sinkers will float on the top!

Do not worry about a bit-o-zinc in your melt.


Cast away.

banger