Colored oatmeal

[Gunslinger1911]

Well I did a bunch of searches, got some conflicting ideas, could have sworn I've seen pix in the past; so here goes .....

Been casting with some bought ingots, couple hundred pounds - no problem.
Casting along, adding ingots as needed, all of a sudden I get a couple inches of very brightly colored oatmeal. I talkin BRIGHT blue !

Fluxed the heck out of it - no joy.

Dipped out all the grunge (half the pot), added new ingots, no oatmeal but not getting great boolits either.

Decided to step back before I got mad; cooled pot - never had that color on top before.
Heated pot up again, no oats but seems to be pouring slowly from spout (PM2 by the way)

Zinc ?

HELP !!!!!!!!!

[Wayne Smith]

A drop or two of muriatic acid will determine the presence of zinc if it sizzles and bubbles up. Easiest way to check.

[Gunslinger1911]

Thanks Wayne, I can get some HCl (same thing) from work.

[GhostHawk]

I never saw bright colors like that unless I was melting very close to pure lead, and got a little bit hot.

Now I don't know about the oatmeal. Not sure I've ever seen it in my pot.
If it is Zinc I would try fluxing it with some sulfur. And I'd watch your temp close, if it does not get hot enough the zinc can't melt.

[Mitch]

i see no metion of the temp the pot was at/i to have never seen anything but pire lrad make the rainbow color.I have nver seen zinc make color like that or be that as corse like in your pics.just guessing here malfinction on the temp of the pot.the wron inigot ummarked or something lik pure that melts at a higher temp than the alloy you were useing.zinc that i have seen is more like slushy snow fine grained stuff. just some guesses here is all.sure will be interesting what is going on when you figure it out.

[BK7saum]

My guess is that you got the pot way too hot. The blue is what you see when you overheat the alloy. As far as the oatmeal, I think you oxidized the tin and antimony out of solution and resulted in poor casting.

[Gunslinger1911]

Thanks for the input guys.
I don't think I got the pot too hot, it's a PM2 (can't trust it) but I have a Lyman dial therm in the melt.
Pretty sure it didn't go over 750
Just adding ingots as usual as needed, noticed the oatmeal when the ingot didn't sink in the melt.
I'm gonna fire it up tomorrow and see what happens. At the worst, I'll dump the pot and start fresh and hope for the best.

[wmitty]

If you have access to some copper sulfate you can place a small quantity on the surface of the melt and once the moisture has been driven out you can stir it into the melt and remove the zinc contamination.

[Gunslinger1911]

I'll have to look in the junk cabinet in my lab, may have some.
Isn't copper sulfate in stump remover or something ?
Gotta remember to grab some HCl to test the slag.

I went full nuclear last night; took the pot outside, heated it up, started fluxing, like I do a smelt - I use pine chips from chain saw, Carnuba Red lube, and / or motor oil. Just dumping the fluxes in (OK, I'm playing here, may learn something).
Just kept fluxing, skimming off the muck - smoking like a coal train ! Lighting the smoke as needed (didn't want the fire dept showing up lol).
Remember, this is just a 22 lb ProMelt 2 and I'm worrying about the FD here !
So we are down about a third of capacity, I have 6 muffin cavity's full of "something really weird looking".
Hmmmmm, what's left looks not too bad.
Heated up my 45ACP HP mould, cast a few; well shoot, those look pretty good !
I'll check hardness tomorrow, but they pass the fingernail test now.
I guess I'l have to "ring" the rest of the ingots and see if I can tell if any more "bad" ones - still gotta test slag with HCl.

Thanks to all of you, I had a path to follow, tests to check - I seem to be good for now.

I have to give a huuuuuge shout out to Dusty Bannister, he sent me a PM (more like a novel), asked questions, gave advice.

Certainly a real "Straight Shooter" and a hell of a guy !!!!

[B.C.Jay]

I have had similar colorings and slush with unknown alloys. My research leads me to think the bright blue coloring is some kind of cobalt oxide/salt. It tends to hang with copper/nickel, and excess copper can cause a slush.

It's hard to guess what the source might be, but I have never had it with any babitt metals, only 'unknown' metals and I suspect it may be be from battery scrap or similar.

My solution was to cool, skim, chuck it... before fluxing.

[Petander]

Sometimes very hot pure looks like that.

I melted some range scrap yesterday, everything FMJ or 22LR only. One batch gave me those rainbow colours again. It'a a very thin film-like layer in the surface only.

It's not zinc,I had my alloys tested. I do have Niobium. HCL reacts with many other impurities.

[Petander]

My todays batch is all golden!

[rockrat]

May be a lot of tin in there!!

[Big Ben]

If nothing else, the color is cool...

[Gunslinger1911]

Casting with my 20 lb dip pot to make some BIG boolets today, rollin along for an hour or two, using older known ingots.
Cast what I needed and decided to add in some boolets from the suspect alloy.
Lo and behold, after about 20 325g slugs here comes the blue.
No oatmeal, just a blue tint to the surface, cast OK.
I have enough alloy I'm just gonna trash the 10 lbs of oatmeal from last week.
Prob ding the ingots before going in the pot, maybe drag out the Lee hardness tester and check the "off" sounding ones.

[468]

Some say to flux in sulphur to help with zinc. Where does one get sulphur?

I haven’t “smelted” in almost 10 years.had some free time so decided to process some wheel weights. I’ve never sorted, just try to keep temp down. My result was similar to OP’s photos, but with much less oatmeal. I concluded that I ran the first batch too hot and the Elements precipitated out of the alloy. I ran the second batch more cautiously...same bucket of wheel weights. Came out perfect.

[SweetMk]

Some say to flux in sulphur to help with zinc. Where does one get sulphur?

I got mine as a garden supply,,
SO you could check lowes, HD,, Walmart on-line has it,,

If you try to grow blueberries,, SULPHUR IS A MUST!!


They say no matter how acidic your soil is,, blueberries needs more Sulphur,,

[468]

Thanks SweetMk.

I checked those biscuits with muratic acid. No bubbles. They’re good, just ugly...kinda like me!

[wmitty]

I have been down both roads; using sulphur and using copper sulfate to remove zinc contamination... I promise you, the sulphur route is unpleasant...

[dondiego]

I have been down both roads; using sulphur and using copper sulfate to remove zinc contamination... I promise you, the sulphur route is unpleasant...

When zinc first started to appear in wheel weights, I had no clue. I got the oatmeal once and just kept adding a few pounds of soft lead and it quickly went away and the boolits came out fine. I did some research here and figured it out.