Hi tek flaking off

[Panman213]

Has anyone else noticed hi tek flaking off after sitting on the shelf for an extended time? When I first coated them, they passed the smash test and the wipe test. I loaded a bunch and they shot great. I stored them in a plastic container. Jumping foward about a year. I went to load the remaining boolits and found that the coating was coming off. Im glad I didnt coat thousands just a few hundred. Do you suppose I did something wrong? Oh well back into the smelting pot.

[HATCH]

could be oxidation under the coating causing it to flake off?

[Ausglock]

Yep. normally the case is oxidisation on the lead due to contaminates.
I have commercially coated bullets here that are around 10 years old.

[Grmps]

You didn't happen to quench the boolits after you cast them? that's an easy way to contaminate the surface.
The cleaner the lead (alloy) the less chance of this happening.

[Panman213]

Thanks for the heads up. I usually store them in a tupperware container (air tight?). But maybe this bunch got contaminated somehow.

[fredj338]

I haven't that many sitting around but I agree, probably something contaminating the bullet surface prior to coating. Do you size prior? If so do you use size anything else in the sizer?

[Panman213]

I only size after coating and usually coat shortly after casting.

[Goodun]

I’ve seen similar issues. Is PC as sensitive too surface contamination?.

[HI-TEK]

could be oxidation under the coating causing it to flake off?

Hatch,
I think you are right on with Oxidation.
I have seen Lead that was contaminated with Zinc, Magnesium, and Cadmium, and they all develop a metal oxide of sort, (powdery white crust) on alloy surface, that develops with time and moisture/humidity.
Any coating, will "breathe" and these active metals will cause problems with adhesion with coatings in time.
I have suggested, that cast alloy that may have such metal contaminations can be soaked in Muriatic Acid diluted with water about 1 part acid to 2 parts Water, and these active metals will dissolve from surfaces of alloy, leaving porous surface. Then, and after thorough washing and drying, these casts can be fairly successfully coated, as the reactive metals are no longer on surfaces of alloy, and pores left on surfaces of alloy acts as better foothold for coatings to bond to metal.

[Petander]

I have thousands of bullets from my past , active casting years. Stored inside,none have any visible oxidation but I couldn't make them work with Hi-Tek. I tried for weeks and took a break. It must be my alloy.

But I tried HCL wash for some bullets just to see what happens:

Attachment 222653


Two days in muriatic acid made the bullets brown and more oxidation started immediately,white stuff is growing on the surface after wash and dry. I decided they can not be coated.

But couple of days ago I thought I might just as well give them a coating... and I got my best coating ever! I mean, I have been shooting these for two days now with no lube - and no leading.

In my case Zn is very much possible , my alloy being mostly wheelweights. Or Fe from my cast iron smelting pot?


Attachment 222654.

The first coat bonds much harder than ever before. Yes I coated those brown bullets! This invisible contamination may be the reason for some other folks problems as well.

I have fresh bullets soaking in the garden right now, I have about a ton of this alloy,cleaned in ingots. Muriatic acid may be the answer, I wanted to try 45-70 and some other calibers but I thought my alloy just won't work.

[Petander]

Here are my fresh test bullets in HCL. Tiny bubbles are coming.

Attachment 222658

[HI-TEK]

I have thousands of bullets from my past , active casting years. Stored inside,none have any visible oxidation but I couldn't make them work with Hi-Tek. I tried for weeks and took a break. It must be my alloy.

But I tried HCL wash for some bullets just to see what happens:

Attachment 222653


Two days in muriatic acid made the bullets brown and more oxidation started immediately,white stuff is growing on the surface after wash and dry. I decided they can not be coated.

But couple of days ago I thought I might just as well give them a coating... and I got my best coating ever! I mean, I have been shooting these for two days now with no lube - and no leading.

In my case Zn is very much possible , my alloy being mostly wheelweights. Or Fe from my cast iron smelting pot?


Attachment 222654.

The first coat bonds much harder than ever before. Yes I coated those brown bullets! This invisible contamination may be the reason for some other folks problems as well.

I have fresh bullets soaking in the garden right now, I have about a ton of this alloy,cleaned in ingots. Muriatic acid may be the answer, I wanted to try 45-70 and some other calibers but I thought my alloy just won't work.

PETANDER
As it was suspected from the beginning, you did not have a good alloy at all. With Hydrochloric Acid the brown stains are generally Iron contamination. White crust type formation can be caused by Aluminium, Magnesium, and most possibly Zinc, and to a smaller possibility Tin and or Cadmium.
As I advised Hatch, back in April, Acid soaking & subsequent washing and drying can produce a surface that will coat using the Hi-Tek. The Acid will pickle off metals available at surfaces, which can be rinsed off. This produces a porous surface that really allows a great foothold on the alloy for the coating to stick well.
The problem you face is that acid treatment is most effective on cast projectiles but now so good with ingots. The Ingots have locked up internally contaminants, so if you aid wash Ingots, then cast, you will end up with same contamination problems with the cast, and have to wash with acid again.

[HI-TEK]

Here are my fresh test bullets in HCL. Tiny bubbles are coming.

Attachment 222658

PETANDER
Previous picture shows KLORINE on the bottle. Is this Acid or Bleach? What is chemical description on label? If it is Chlorine Bleach, (Sodium Hypochlorite Solution), this contains about 4% Caustic soda. This Caustic will react with Aluminium, and Zinc, forming bubbles. Unfortunately the Caustic will also start to dissolve Lead. You don't want this. NOT good at all.
Please check and advise.

[Petander]

Thanks a bunch,Joe. It says "Natriumhypokloriitti", no chemical label.

Desinfection cleaner it is, Na is sodium in english so yes, this is sodium hypochlorite. NaHcl.

Dang. I'll see what it does to my test batch. Those brown bullets got the first coating soooo goood, no matter how I scratch,it will stick. And the next coatings stay,too.


I don't have a problem with soaking bullets if it makes them good for coating. I'll see if I can find HCL only.

[HI-TEK]

Thanks a bunch,Joe. It says "Natriumhypokloriitti", no chemical label.

Desinfection cleaner it is, Na is sodium in english so yes, this is sodium hypochlorite. NaHcl.

Dang. I'll see what it does to my test batch. Those brown bullets got the first coating soooo goood, no matter how I scratch,it will stick. And the next coatings stay,too.


I don't have a problem with soaking bullets if it makes them good for coating. I'll see if I can find HCL only.

PETANDER

You have confirmed my worries that you used Sodium Hypochlorite solution and not Hydrochloric Acid.
This explains also the RED/brown deposits. It is essentially Rust, (Iron3Oxide).
Bleach is an Oxidising substance that made the rust in combination with the contained Sodium Hydroxide.
You must have a lot of other contaminants in your alloy that caused the bubbling. Iron does not react with Caustic that way, but combination of active Chlorine with Sodium Hydroxide caused the brown rusty deposit. The Caustic in the Bleach, may have removed the other contaminants such as Zinc, Magnesium, and Aluminium, that left a reasonably inert porous surface for the coating to bond.

Please discontinue using Bleach as a cleaner for your alloy.
It may work as a cleaner but downsides are very unhealthy.
Sodium Hydroxide in the bleach readily dissolves Lead, and makes it a water soluble salt. Then this solubilised Lead is easily and rapidly absorbed through the skin.


The Acid targets the more active metals such as Iron, Aluminium, Zinc, Magnesium. All of these become soluble in the acid cleaner. Any traces of Lead that may be dissolve helps to remove these other contaminants by electro chemical displacement process.


Getting back to the coatings, the above, is why I do get upset, when the true picture is not presented in the first place.
A correct diagnosis would have solved problems quickly, that your alloy was so badly contaminated.
I would have told you not to use the coatings until you fixed your alloy.
The results you would have had with coating, using the cleaned alloy, would have worked the first time, and not had the failures over weeks of your efforts.
Bonding problems was not the coating, drying or baking, but your alloy contaminations.

[Petander]

Yep I see that now. I know your coating is good,never blamed it. I'm sorry if my posts looked like that.

My first oven started to behave on its own as well,without me paying attention after the initial setup. I have a big,powerful oven now. I did some batches in too low a temp with the "toaster oven".

This bleach thing was just another test... I'm glad I did it though. Because now I know better.

I'll see how it goes with straight HCL.

[Petander]

Oh,I'm not touching that liquid bleach thing at all. No skin contact.

I only tried that once,that's it.

Thanks for the exellent chemistry lesson. This feels good now, it's very difficult to judge the quality of the coating when one has never seen,touched,smashed or rubbed a proper coating before.

Now it bonds like crazy AND the third coat won't flake or anything like that. It's not like paint on the surface anymore. It's like colored lead.

Here are the "rusty" ones,coated a bit too hot three times. Left to right, first,second and third coat. Two bullets smashed for each coat. Colour is a random mix, green got some purple from the bowl. I have fired several boxes without problems. Clean barrel. And excellent accuracy,that's why I stick to this bullet in the first place.

This is a wheelweight country I live in,no way to get commercial alloys.

Attachment 222709

[HI-TEK]

Oh,I'm not touching that liquid bleach thing at all. No skin contact.

I only tried that once,that's it.

Thanks for the exellent chemistry lesson. This feels good now, it's very difficult to judge the quality of the coating when one has never seen,touched,smashed or rubbed a proper coating before.

Now it bonds like crazy AND the third coat won't flake or anything like that. It's not like paint on the surface anymore. It's like colored lead.

Here are the "rusty" ones,coated a bit too hot three times. Left to right, first,second and third coat. Two bullets smashed for each coat. Colour is a random mix, green got some purple from the bowl. I have fired several boxes without problems. Clean barrel. And excellent accuracy,that's why I stick to this bullet in the first place.

This is a wheelweight country I live in,no way to get commercial alloys.

Attachment 222709

PETANDER
Aside from coating being over cooked and darkening with colour, they are all fine. You have done well.
You repeated over baking and proved that the over baking will not harm performance but only the final colour.
With wheel weights, every country has their own idea of what wheel weights should be made from. Unless you can find out the brand, and maker tells you composition, it is only a Guess at best if you have an alloy that may be suitable.
This is why, experienced wheel weight users know what is good and what needs work to make it usable.
There is a lot of information on this blog site about alloy refining, and hardening, it is just a situation of having to read advice from people who have done the refining themselves.
You have to remember, that more active metals such as Zinc, Magnesium, Aluminium, will interfered with good bonding, as they all react with the coating, and stop it sticking well.
You simply have to try and remove these metals by various ways first, so you can use the refined alloy.
Attached is picture of over cooked coating and resultsOver Cooked coating.pdf

[Petander]

Yes,WW is a big mystery,I just happened to have thousands of old 9mm bullets that I wanted to try first.

I still have thousands ,also in different calibers. I did try to coat straight linotype too,without understanding how it could be contaminated too. Well,it's the doggone same cast iron pot that I have used to smelt and make ingots from ww and pure and 22LR scrap... they all must have at least Fe.

Here is day three in bleach,recently cast bullets. Such a simple way to analyze contamination.

Attachment 222751


I have enough alloy for 100 000+ bullets. I have survived 35 years of music business and a heart attack, I will make this a relaxing hobby again.

[HI-TEK]

Yes,WW is a big mystery,I just happened to have thousands of old 9mm bullets that I wanted to try first.

I still have thousands ,also in different calibers. I did try to coat straight linotype too,without understanding how it could be contaminated too. Well,it's the doggone same cast iron pot that I have used to smelt and make ingots from ww and pure and 22LR scrap... they all must have at least Fe.

Here is day three in bleach,recently cast bullets. Such a simple way to analyze contamination.

Attachment 222751


I have enough alloy for 100 000+ bullets. I have survived 35 years of music business and a heart attack, I will make this a relaxing hobby again.

Petander
It seems that recently cast also has some sort of contamination. It looks like Iron from brown stains on surface.
If you then wash this with water first, then soak in dilute Hydrochloric Acid, the acid should get rid of the brown rusty appearance
and remove more unwanted contaminants like Zinc, Magnesium and Aluminium..
HCl that is suitable that is used as Concrete cleaner, available in hardware stores. It is also known as Muriatic Acid.
Use2 parts water and add 1 part Acid to the water, then pour diluted acid onto projectiles and use plastic containers only for acid soaking.
Soak overnight, and have a look the next day. Use Rubber gloves, and wear goggles to protect your eyes from plashing acid into it.
Keep it outside somewhere. I would be interested in what happens after acid wash. If it looks OK next day, pour off diluted Acid into another container containing projectiles requiring cleaning.
Then wash the acid soaked alloy thoroughly with water. Dry well, even if warm air drying is needed. Then coat and see what happens.