# My first bar



## fishntrox (Jul 31, 2011)

Here's my first bar which weighs 39.3 grams. I have been making little gold buttons from pins and fingers using the electric cell & AP process. After several months of study I finally bought some nitric and made this bar from 10k & 14k jewelry. It is twice refined, although I was very tempted to melt after the first refining. I know it's not the best looking bar, I still need to practice pouring in the mold. Are there any tricks I'm missing while pouring the gold? The bar is a whole lot more shiney than the pic shows.


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## samuel-a (Jul 31, 2011)

This bar looks fantastic fishntrox.

The bar, as i see it, was poured into a vertical mold (adjustable?)
In this case, you need to pour at a bit higher temperature of the melt and heat the mold thoroughly with a torch so the metal won't freez so fast.
The biggest disadvantage of heating cast iron is the formation of oxides that you will need to clean later with fine sand paper if you want to pour fine gold again in it.

You'd also want to soot the entire inside of the mold lightly with a candle or fuel based torch before (if you didn't)


Two more thing..
When you adjust the mold, calculate it to the exact pour volume + 20%, this had worked out fine for me so far.
Also, when you pour, it most be done with one constant & confident pouring movement, like a machine if you will...


All in all, it's mostly practice and steady hands.
Good luck


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## TigWiz (Jul 31, 2011)

I love this bar, it has a lot of character. Good job.


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## Harold_V (Aug 1, 2011)

samuel-a said:


> The biggest disadvantage of heating cast iron is the formation of oxides that you will need to clean later with fine sand paper if you want to pour fine gold again in it.


Oxidization of the mold (not rusting) is a *very good thing*, and should be encouraged. If the mold has been properly prepared, the values never touch metal, so there is no fear of contamination. Keeping a mold bright and shiny isn't a good idea at all. 

I used to blue my molds intentionally. That helps limit gold's ability to solder to the mold, which isn't all that hard to accomplish, in particular if you're pouring a fairly large ingot and it is poured all in one place. That has a tendency to burn through the soot coating, so a clean surface guarantees the ingot will solder to the mold. 

To blue one, simply heat until it turns blue, then allow it to cool. Before use, it should be preheated, then well covered in soot, as you suggested, either by candle, or with an oxy/acet torch. It should be preheated quite hot, but below a temperature at which carbon will burn. The soot layer helps prevent soldering, and ensures the ingot will release properly. 

Harold


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## samuel-a (Aug 1, 2011)

Hi Harold

Thanks for sharpening that point.
Just to be clear, i was reffering to the rust forming after storing a used iron mold.

Do you know of any trick to prevent that?


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## nickvc (Aug 1, 2011)

Sam spray your moulds with wd40 or similar product after they cool, it's what I use as a bar release agent anyway and it works ok for me.


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## fishntrox (Aug 1, 2011)

The mold I used was a graphite mold I bought off ebay. I torched the mold w/ a propane torch while melting the gold. Then before pouring I put the ox/acc torch on it for a few seconds. Then I heated the gold some more before pouring. I'm thinking I just didn't get the gold hot enough to make a smooth pour. But I'm not 100% sure.


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## Geo (Aug 1, 2011)

the bar you made looks great for a first attempt.try heating the gold as you pour.also you can place a cast iron skillet on a hotplate and place the mold in it and set to high setting and wait till the mold heats up,then when you pour you can heat the gold in the mold with your torch to make it uniform.its called "fire polishing".


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## fishntrox (Aug 1, 2011)

I will try that next time Geo. Thanks! And many more thanks to the fine members of this forum. Had it not been for you all I never would have been able to do this.


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## avalokitesvara (Nov 16, 2011)

hi; i'm a new in this gold refinery and casting business; and i'm pretty confused in creating a totally smooth glass-like surface, especially the bottom part.

i've met and request some steel making masters to make me some steel based molds, but out of all 8-10 molds it gave me the same output, it cannot be the same like when i bought some imported gold bars such as perth mint.

i've tried several way such as giving the mold oil / fats / some carbon.... but i still cannot make the smooth surface especially at the bottom.;

i doesn't have any problem with the upper surface as i've learn from my senior that we have to keep the surface blown away with the torches slowly but sure to keep the 'dirt' moves to the side....

also one more thing, which is better, to cool it down the gold bar directly to the water with the mold, or just the gold bar?
or should i just leave the gold bar cooled it down by itself within the steel mold? (as far as i know it the bottom will be black if i leave it too long on the steel mold.)


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