Dirty ugly Ingot, please advise

[Javater]

Hello Boolit casters,

I got some pewter and melted them down and i am seeing imperfections and would like to ask for your wisdom to fix it.
1. i am getting alot of cratering on the bottom of the ingot. how do i get rid of it? what did i do wrong?
2. i am seeing a sheen of gold yellowish tint on top. how do i get rid of it? what did i do wrong?
here are the pictures.
I spent only about 8 dollars for 1lb little over 13 ounces of pewter.
182291182292

Thanks much,

[RogerDat]

You used a muffin/cupcake tin and there is non-stick coating or build up of pam/grease. This boils off gasses when hit with molten metal so you get bubbles. After a few uses the stuff that is off gassing will be burned off. Plain lead melts at higher temp and will burn off that stuff that is off gassing faster than using with pewter. Non-stick once it turns dark and burnt looking is pretty much done off gassing.

Gold tint is typical of high tin alloys, I think it is related to casting temperature. Might not have it at cooler melt temps or maybe a cooler mold. Hurts nothing and is common so not unexpected in home made pewter ingots. About 1/2 of mine are shiny silver and very smooth and about half have the gold tinged or even solid gold coloration.

[Javater]

Thank you RogerDat, i was thinking i messed up somewhere. Yes Muffin tin are "New" to me and it was used before for cooking food
Its great to hear that Gold tint is normal for high tin.
Anyway i can speed up the blacking process of the muffin mold? I put a blow torch to it and it was burning my wood under it. maybe more is needed?

[Oklahoma Rebel]

be careful! it could crack if heated unevenly. I hope you get this in time, that would be crappy

[Oklahoma Rebel]

well, if it is cast iron, that is, lol. I was assuming and you know what that does!

[RogerDat]

It has been a total carp shoot how long those garage sale ingot molds take to clear up. Some are good after a couple of uses on the other hand I have two bread loaf pans I use for larger ingots that still blow bubbles after many, many fillings with molten lead. Some folks advocate for setting out to rust, claiming rusty ones don't stick and work better. Dear wife would drop the hammer on me if I put a bunch of baking tins out to rust.

Rebel is right cast iron cracks if you make the mistake of only heating one part of it. Or of quenching it with water so it cools too rapidly in one area. But it does hold a consistent temperature very well. Just requires some care if hitting with a torch that the whole thing is heated evenly.

If you get the plain metal ones be sure to test one cup before filling all cups, every so often I find an aluminum one that the lead bonds with have to beat the resulting puck out of the pan. Best to find this out with one cup filled not all 6 or 12. I found that out the hard way. Which means I'm not likely to make that mistake again eh?

[William Yanda]

I have had buyers say of the gold tint; "Tinted gold, just like I like it."

[Javater]

well, if it is cast iron, that is, lol. I was assuming and you know what that does!
nope not cast iron. its cheapo prob alumin?

[Javater]

It has been a total carp shoot how long those garage sale ingot molds take to clear up. Some are good after a couple of uses on the other hand I have two bread loaf pans I use for larger ingots that still blow bubbles after many, many fillings with molten lead. Some folks advocate for setting out to rust, claiming rusty ones don't stick and work better. Dear wife would drop the hammer on me if I put a bunch of baking tins out to rust.

Thanks for the advice. I "may" put them out to rust since we are not going to bake food with them.
As for 1 muffin cup at a time is a good idea.

[Javater]

Thanks all, I have good results after burning the muffin pan with blow torch.
New questions is why am i getting gold sheen during the lead melt? It poured great, but i gave up skimming the gold sheen on top after 15 mins. 182366

[runfiverun]

the gold is your Tin.
keep it in the alloy.

[RogerDat]

gold sheen it generally tin, but pure lead can have a blue/black/purple sheen on it. Both of these are normal and too be expected.

And lead in general, or it's alloys will oxidize (combine with oxygen) to make a gray sort of dusty film on top. Use a small piece of wax to drive that dusty film back into the alloy. Bees wax is supposed to be best but the cheap candles at Salvation Army store or from garage sales work just about as well, just burst into flame a bit easier. Can be sort of wild, as the wax melts and spreads out and slides across the surface it leaves a shiny patch behind where the oxides have been reduced back into the melt. Then suddenly Whoosh it bursts into flame. Some folks light the wax with a long BBQ lighter as soon as it all melts just to burn it off faster. Talking about a chunk the size of a lima bean in a 100# pot. Maybe pea sized in a 20# casting pot. I tend to save my more expensive bees wax for the casting pot and use the cheap stuff for the smelting into ingots.

[Javater]

I used Saw dust......its free from my shop Should i be stealing my wife's candles?:roll:

[RogerDat]

I used Saw dust......its free from my shop Should i be stealing my wife's candles?:roll:

I am NOT going to advocate stealing from wife, as the man said, you gotta sleep sometime better to piss off someone who doesn't have keys to the house. I think I might have spent around $2.50 for about 8 full length candles at Salvation Army.

Sawdust does one thing, wax does another. The sawdust helps pull impurities out, wax reduces oxides back to original metal. Tin tends to oxidize faster than the lead and other alloys so the skim on top is high in tin, wax forces it to transition from a tin oxide back to tin.

[Javater]

RogerDat, I though they were both for removing impurities... I guess i will go to Walmart and buy some cheap tea candles.
This forum and them members here are godsend.

[pcolapaddler]

RogerDat, I though they were both for removing impurities... I guess i will go to Walmart and buy some cheap tea candles.
This forum and them members here are godsend.
If you have one of the 'everything is $1' stores, you can get tea candles and such there for a buck. Probably a bit cheaper than Walmart. Sometimes these stores are a good source for stuff and they are often in the strip with Walmart.

Sent from my HTCD200LVW using Tapatalk

[Strtspdlx]

I preheat my Ingot molds to reduce the divot in them. I've had very good luck doing this. Mostly all my I gots show no signs of it now. I used to use a grill for rendering down and I would stick the mold on the grill surface and allow it to warm up with the pot. Pouring into a dead cold mold will give you poor fillout so why would it be an different when making Ingots. Or Atleast that's how I rationalize it. So that's my story and I'm sticking to it.
As for the gold sheen, don't put too much thought into it. It's high tin. But keep in mind the more heat you put into it the more it will oxidize the tin and you'll essentially burn some off. How much is actually burning off I have no idea. It may be such a small amount that you'll never notice. I honestly don't have the answer to that question.

[RogerDat]

With cold weather pre-heating ingot molds becomes even more critical. Transition from cold to hot can yield condensation (moisture) as you pour lead into the cold mold and it will "pop" splashing lead back out, could even yield an explosive visit from the tinsel fairy. Same for ladles and spoons. Sticking a cast iron ladle directly I got enough of a "recoil" that it made a long term impression on me about the power of moisture and molten lead.

Hitting the top of the lead with a propane torch will also help reduce the collapse into the center from cooling. But I think Strtspdix is correct the cold mold causes the sides to harden rapidly and then as the lead cools the center contracts away from those hardened edges.