simple Hi-Tek coating

[Petander]

Petander,
I think your Yellow dross may be solved. There are two forms of Lead Oxides.
PbO (lead (II) oxide, litharge) : red
PbO (lead (II) oxide, massicot) : yellow
(Same chemical formula, different crystal structures)
It seems, that you have made the yellow version with your mystery composition alloy.
I don't know how it was produced, but that is most likely explanation for your Yellow dross.

Maybe this is gold?

This alloy is Rio brand factory trapshot only,BHN 8. I've never seen this with my own alloys.



.

Acid wash made my cast RB:s completely black,indicating heavy contamination.

[HI-TEK]

Maybe this is gold?

This alloy is Rio brand factory trapshot only,BHN 8. I've never seen this with my own alloys.



.

Acid wash made my cast RB:s completely black,indicating heavy contamination.

What was the colour of the acid wash? Was there a lot of fizzing? I am not certain why acid washed Lead turns black. That is also a mystery...

I have had another option for gold colour on Dross.
I am wondering if that gold came from someone using Gold Hi-Tek on cast.
The Gold is very temperature stable, and easily survives at melted Lead temperature, and it will float on top of molten Lead.
I wonder, as quite a few have obtained some gold in your country.

[Stephen Cohen]

What was the colour of the acid wash? Was there a lot of fizzing? I am not certain why acid washed Lead turns black. That is also a mystery...

I have had another option for gold colour on Dross.
I am wondering if that gold came from someone using Gold Hi-Tek on cast.
The Gold is very temperature stable, and easily survives at melted Lead temperature, and it will float on top of molten Lead.
I wonder, as quite a few have obtained some gold in your country.

I recently god some gold dross while smelting range scrap, I thought it may have been sulphur residue from someone trying to remove zinc, seems you have solved the riddle Joe. I have to admit that in the last few years wheel weights and range scrap can be anything. Regards Stephen

[Petander]

What was the colour of the acid wash? Was there a lot of fizzing? I am not certain why acid washed Lead turns black. That is also a mystery...

I have had another option for gold colour on Dross.
I am wondering if that gold came from someone using Gold Hi-Tek on cast.
The Gold is very temperature stable, and easily survives at melted Lead temperature, and it will float on top of molten Lead.
I wonder, as quite a few have obtained some gold in your country.

That ammo/shot comes from Italy. I had nothing else in the pot. Maybe I'm just hitting a sweet spot for this kind of oxidation,casting pure lead hot @ 850°F.

HCL itself doesn't change much in colour at all. My own alloy turns gray when soaked, this trap shot got completely black really. The black "dirt" rinses away leaving lead looking dark grey like pure lead. Which it is,being BHN 8.

Quite a lot of fizzing and tiny bubbles,yes.

Coating is very good,two coats here:

[HI-TEK]

I recently god some gold dross while smelting range scrap, I thought it may have been sulphur residue from someone trying to remove zinc, seems you have solved the riddle Joe. I have to admit that in the last few years wheel weights and range scrap can be anything. Regards Stephen

Hi Stephen,
Sulphur at melted Lead temperatures would evaporate and or catch fire. Melting point of Sulfur is much lower that Lead.
You mentioned Zinc removal, this is an important area.
If casts are made with Zinc contaminated Lead, if it is acid washed, the acid can in majority, removes available Zinc on the cast surface. If there are cast "holes" pores caused by Zinc, the acid will penetrate and attack exposed Zinc.
Once Zinc is dissolved, it should leave a porous surface. That is ideal for Hi-Tek.
Because of various Gold's being so popular, and used for many years, it is not surprising that shot range scrap would also contain Gold Hi-Tek coatings which should show up with the recycled Lead as dross on top.

[Petander]

Theory is good but this is not range mystery alloy. I'm converting factory trap ammo to round ball slugs.

[Stephen Cohen]

Hi Stephen,
Sulphur at melted Lead temperatures would evaporate and or catch fire. Melting point of Sulfur is much lower that Lead.
You mentioned Zinc removal, this is an important area.
If casts are made with Zinc contaminated Lead, if it is acid washed, the acid can in majority, removes available Zinc on the cast surface. If there are cast "holes" pores caused by Zinc, the acid will penetrate and attack exposed Zinc.
Once Zinc is dissolved, it should leave a porous surface. That is ideal for Hi-Tek.
Because of various Gold's being so popular, and used for many years, it is not surprising that shot range scrap would also contain Gold Hi-Tek coatings which should show up with the recycled Lead as dross on top.

I agree with all you said Joe, I have used the sulphur method to remove zinc from badly contaminated lead, and it does catch fire and stink no end, it is only in recent months I have learned about the acid treatment from your advice to Petander and yes it does work a treat. I don't know what we did before this coating become norm, a week never goes by when someone does not give me a handful of cast to coat for them to try. Regards Stephen

[hunter74]

This is what 6% Zinc in the alloy looks like. I had it tested

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[HI-TEK]

This is what 6% Zinc in the alloy looks like. I had it tested

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WOW, that looks really bad. It can only be Yellow Lead oxide, as Zinc, and its oxides are white not Yellow. Do you have the analysis results. It may shed some light on what was found.

[HI-TEK]

Theory is good but this is not range mystery alloy. I'm converting factory trap ammo to round ball slugs.

My theory is not theory at all.
It is quite possible that your alloy simply ends up with Yellow Lead Oxide and no Gold from Hi-Tek coatings. Here, the Gold coatings have been used for 20 plus years in indoor and outdoor ranges and in very high volumes. I would not be surprised at the results of Gold appearance showing up in dross from locally reclaimed Lead from these areas. As I said, the "Gold" is temperature stable above 600C, and is stable well above molten Lead. It simply floats to the top of Molten Lead without any other reaction or nasty fumes, like Sulphur produces.

[Petander]

Hunter74, was your alloy very hot?

I remember making my first pure lead ingots,I got all the rainbow colours when melting it. It was confusing after years of wheel weights / linotype.

[hunter74]

Sure, here's a pic of the XRF results.



The alloy got too hot. It went up to 750 F or so before pouring the ingots. No matter how much I flush I can't get rid of the yellow dross. It also makes yellow smoke when stirring the pot.

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[Tazza]

I have had yellow dross years ago when melting unknown indoor range scrap, i have no clue what it was either, all i know is i make sure to keep it away as it looked toxic. I thought sulfur too, but as stated, it would have burnt up.

The odd thing is, range scrap from an outdoor range i have done a few times, i never got this yellow dross, so it's very weird.

Both sources of lead, make great projectiles, so whatever it is, it never seemed to make any issues.

I have had the blue-yellow rainbow colours on pure lead ingots too, but lower themerateures seem to prevent this.

[HI-TEK]

Sure, here's a pic of the XRF results.



The alloy got too hot. It went up to 750 F or so before pouring the ingots. No matter how much I flush I can't get rid of the yellow dross. It also makes yellow smoke when stirring the pot.

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The test shows Titanium at 1.2%. That is a strange metal to have in a Lead alloy.

[HI-TEK]

Hunter, I believe that the Lead was far too hot, and was reacting with Oxygen to form the Yellow form of the Lead Oxide.
By your stirring you constantly exposed more Lead to Oxygen to form more Yellow Lead Oxide, which became airborne dust.
Very bad situation. There are many warning about excessive heating of any Lead alloy, where even Lead vapours are generated.
In a Foundry situation, the metal is shielded by inert gas to stop Oxidation. If they are refining with excessive heat, or dissolving Antimony, all gasses emitted are sucked into and scrubbed by metal fume capture system. Any oxidation taking place is loss of Metal, which has to again be reduced from the Oxide by reducing agents such as Iron dust or granules. The Iron extracts Oxygen from Lead Oxide forming essentially Iron Oxides, and this reaction liberates back the Lead.

[hunter74]

I'm sure you are right about too high heat and oxidation. Anyway the lead contains way too much Zn to be usable for casting the way it is. I have about 50 kilos of this alloy and I most likely will trade it in for new lead where I got it. At first I thought about thinning it out to <1% of Zn. By experience it can be usable for boolits when under 1% Zn but I don't think I'll bother.

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[HI-TEK]

I'm sure you are right about too high heat and oxidation. Anyway the lead contains way too much Zn to be usable for casting the way it is. I have about 50 kilos of this alloy and I most likely will trade it in for new lead where I got it. At first I thought about thinning it out to <1% of Zn. By experience it can be usable for boolits when under 1% Zn but I don't think I'll bother.

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Hunter,
You can get rid of Zinc by various ways.
1. Use Lead Sulphate from old car batteries, The Zinc will react with this and release Lead, and then form Zinc Sulphate dross.
2. You can also use Copper Sulphate, available from most agricultural supply store. The Zinc will react with this releasing Copper into the Lead, and the Zinc will form Zinc Sulphate dross.
Essentially you remove the Zinc very easily to an acceptable level.
Alternatively, as Petander did, simply cast, then acid wash to remove surface Zinc. This will help with coating as well.
All above can supply a usable alloy.

[hunter74]

My Bullet Master drips too much with Zn alloy. I have tried and it's too much of a PITA for me to do again. I'll try to get either of the sulphates you suggest. Thanx

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[Petander]

Alternatively, as Petander did, simply cast, then acid wash to remove surface Zinc. This will help with coating as well.

I don't have Zinc in my main alloy though, only Niobium (!!!) and copper.

.

This blackening trap shot may have anything though. I'll send it for test,just out of curiosity.

[HI-TEK]

I have had yellow dross years ago when melting unknown indoor range scrap, i have no clue what it was either, all i know is i make sure to keep it away as it looked toxic. I thought sulfur too, but as stated, it would have burnt up.

The odd thing is, range scrap from an outdoor range i have done a few times, i never got this yellow dross, so it's very weird.

Both sources of lead, make great projectiles, so whatever it is, it never seemed to make any issues.

I have had the blue-yellow rainbow colours on pure lead ingots too, but lower themerateures seem to prevent this.

Tazza, I suggest, that you use iron filing, or get machine shop granular Iron/steel. The finer you can get with this iron/Steel the better. Put this onto your molten Lead that has the dross and stir carefully. The iron will react with the Lead Oxide and liberate the Lead back into bulk. Result is, that you will then get Iron Oxides and reduce Lead losses with formation of Oxidised Dross..
Years ago, I used stuff called Ferrum redactum which was a fine granular deoxidised pure Iron powder. Ebay is selling Iron powder in bulk bags if you are refining a lot of scrap alloy. It is quite expensive.
It is cheaper to get turnings from a machine shop, Steel supply store, where they cut a lot of steel with rotary cut off disc saw. They will give it to you to take away.