# First gold blank



## Noxx (Sep 24, 2009)

Here is the first bar I made using a press and a few other tools.

Sorry for the bad quality pic. I used my webcam. I'll try to post a better one this week-end.

P.S. It looks much better in real


----------



## Harold_V (Sep 24, 2009)

It's not easy to see much detail, what with your web cam and my outdated monitor, but it looks pretty nice, Noxx. I'll be interested in seeing more.

How much tonnage did it take?

Harold


----------



## Noxx (Sep 24, 2009)

It took 12 tons and I pushed the press to its limit.

I'll need much more tonnage for the stamping.


----------



## lazersteve (Sep 24, 2009)

Looks really nice Noxx.

I just purchased a rolling mill hoping it would allow me to make smooth sheets that could be punched into discs then laser etched as 'coins'.

The mill has a very narrow opening and therefore doesn't lend itself readily to working directly from gold buttons fresh out of the furnace. They are way too thick which requires the button to be hammered thin enough to make it into the mill opening. Besides that the mill requires way more force to turn than I thought it would. It's pretty much impossible for me to work it right now with my bum hand from the surgery. Maybe when I get back to nearly 100% I'll have better results.

I guess I'll need to get my hands on a good press to get that smooth finish I've been looking for. Do you have a photo of the press you are using?

Great job!

Steve


----------



## EDI Refining (Sep 25, 2009)

Au supplied by P3M 

That blank looks quite professional to me so far, cant wait to see the result after the die press.

Noxx, something interesting I found, though they have stopped producing/selling them.
https://online.kitco.com/splash/index.html


----------



## Noxx (Sep 25, 2009)

Thanks 

Yeah, then I guess it's time to take Kitco's place :lol:


----------



## jimdoc (Sep 25, 2009)

Noxxco


----------



## Noxx (Sep 25, 2009)

No, no... NikOr Inc.


----------



## Noxx (Sep 25, 2009)

Here are more pics with a cheap 4 MP camera.

















The gold's surface is not perfect yet, it needs a bit more polishing.


----------



## Noxx (Sep 25, 2009)

lazersteve said:


> Looks really nice Noxx.
> 
> I just purchased a rolling mill hoping it would allow me to make smooth sheets that could be punched into discs then laser etched as 'coins'.
> 
> ...



Steve,

Lazer etching gold to make coins sounds a bit tricky to me. I suppose you will be using some lazer CNCs ?

Rolling mills are a must. I guess the one you have is adjustable from 0mm to 5mm ? 

On my side, I used my school's rolling mill and it was quite easy to operate. The handle is quite long thus giving the operator a mechanical advantage. I'll have to buy one because the one I used is dirty and it surely contaminates my gold.

The press we have at school is a benchtop manual laboratory press made by Carver. Here is a pic I took on google:


----------



## Gold (Sep 25, 2009)

Very nice Noxx. 8)


----------



## Harold_V (Sep 26, 2009)

In spite of being pure, gold still work hardens, so it's mandatory that it be annealed when rolling. If you fail to do so, even if you succeed in rolling the material, it's likely to crack. It will come out extremely rigid and hard, making it difficult to work with for any future operations (such as coining). 

You won't believe the difference it makes to heat it dull red, then allow it to cool, or plunge it in water. 

I used to own a set of power rolls, made in Italy. Flat rolls on one side, with wire rolls on the opposite side. Sold them when I sold the refining business. They are now owned by one of my previous customers, in Ogden, Utah. 

Harold


----------



## Oz (Sep 26, 2009)

I was aware of the work hardening aspect of pure gold but not the specifics of its annealing. You statement leaves me still wondering. Steel is annealed by taking to red heat and cooling as slowly as possible. Copper is annealed by taking to a red heat and quenching to cool it as rapidly as possible. 

When you say to take gold to a dull red heat and allow it to cool, or plunge it in water I am still left wondering. I’m not trying to bust your chops, but I am still unclear as to how to anneal pure gold.


----------



## Harold_V (Sep 26, 2009)

Steel is hardened (usually) by the carbon cycle. That has nothing to do with non-ferrous materials, gold specifically.

Everything you need to know to anneal gold has been presented here---you simply have options in cooling, which has nothing to do with annealing. If you heat gold to a dull redness, it will be annealed. The same is true for copper. It does not require quenching for annealing. 

The advantage of quenching, if you care to take that route, is that it rapidly cools the material, making it possible to be handled sooner, and tends to clean the surface in the process. Otherwise, there is no real advantage in quenching. 

Assuming you attempted to anneal a material that formed oxides, the rapid quench tends to shed the oxide coating, so that's to advantage, to say nothing of limiting the amount of time the heated material might be exposed to the atmosphere. I used to cast large copper bars for recovery of silver. I relied on the quenching to clean the bars. 

Harold


----------



## Oz (Sep 26, 2009)

If I understand you correctly gold does not go through a phase similar to steel (martensite or austentite). From blacksmithing my understanding was that iron formed a martensite (high hardness) due to the rapid cooling that traps the carbon atoms instead of letting them diffuse. This is why low carbon iron could not be hardened by quenching. 

The austentite state on the other hand is promoted by allowing the carbon to escape its matrix before the iron has cooled.

I really did not want to belittle the point with technical descriptions that often do not work out in the real world. If based on your experience gold that is taken to a dull red heat is annealed regardless of the rate of cooling that is good enough for me.

It also rings a bell that rapid cooling sheds oxides regardless of the element based on my experiences.


----------



## Harold_V (Sep 26, 2009)

Oz said:


> If I understand you correctly gold does not go through a phase similar to steel (martensite or austentite). From blacksmithing my understanding was that iron formed a martensite (high hardness) due to the rapid cooling that traps the carbon atoms instead of letting them diffuse.


That's not what happens. When carbon bearing material (steel) is heated to the critical point, its structure, which was body-centered cubic, is transformed to face centered-cubic. Rapid quenching prevents the face-centered cubic from returning to body centered. That is the mechanism by which steel (or iron, assuming it has enough carbon dissolved within) is hardened. 



> That is why low carbon iron could not be hardened by quenching.


Mild steel, or steel with less than roughly .3% carbon, can't be hardened because it lacks the required percentage of carbon that is transformed upon heating, although I recently read an article that claims that even mild steel can be hardened if it is quenched rapidly enough. Tends to go against the rules, but I am not a metallurgist, so I am unable to refute or support the idea. 



> I really did not want to belittle the point with technical descriptions that often do not work out in the real world. If based on your experience gold that is taken to a dull red heat is annealed regardless of the rate of cooling that is good enough for me.


It's not only my opinion, it's supported in fact. 

Here's a little test you can perform so you will understand better. If you have access to rolls, roll a small piece of gold without annealing. You'll notice that each pass through the rolls will be harder than the previous pass. It's not attributed to increased surface area alone, it's because you are cold working the gold, which responds by work hardening. After you have taken your piece through the rolls maybe three times, you'll find it quite hard, springy, in fact. If it is quite long, it will support itself when held horizontally. Now, place it on a piece of fire brick and heat it to dull red. Do not quench. When it has cooled, hold it horizontally and tell me what it does. Next, run it through the rolls, making it thinner yet. Tell me how hard it was to send through the rolls after annealing, as compared to the last pass before annealing. 

For the record, work hardening and the carbon cycle have nothing in common aside form each of them making the metal in question harder than it once was. 

There is yet another process for hardening, and it encompasses both ferrous and non-ferrous alloys. It's called precipitation hardening, which is the method by which aluminum is heat treated (artificially aged, and then only certain alloys) and many other exotic alloys. Vascomax is one of them. Vascomax 350 can be heat treated to 350,000 psi, and it does not require anything but an air quench. Heat treat is accomplished in the furnace, at reasonably low temps, where hardness is created by crystal growth. 17-4 PH is such an material. There are also many air quenching tool steels. 

Harold


----------



## Oz (Sep 26, 2009)

I questioned you because I respect your opinion and you have had more years than I to gather empirical knowledge. Empirically I know more about iron than gold as I have spent many more man hours blacksmithing than refining. It will be fun performing the experiments you propose and I will report back as usual. Because of my iron working past, gold has always cofounded me when it comes to temper/hardness. You have also enlightened me as to copper, as I had always though that the rapid quenching was required for annealing.


----------



## peter i (Sep 29, 2009)

I understand that you are confused, but as Harold wrote, the principle behind the hardening is different.

In steel hardening you want to have the hard "high temperature structure" at room temperature. So you heat the steel to high temperature, and quench it. The quench is so fast, that the steel is "frozen in the high temperature structure" before it can change to the low temperature structure. There is an energy barrier to the transition, and once cold, the barrier is too high.
For the same reason, when you want the steel to be soft for filing or cutting, you heat it and let it cool as slowly as possible, giving it ample time for the transformation to the low temperature phase.


When working a piece of metal, you introduce defects in the crystal structure, and this makes it harder. When you heat it, you add the energy (and mobility) to the metal that will allow the structure to "heal" the defects. It is thermodynamically preferable to have a structure with fewer defect, but once again the energy barrier prevents the rearrangement from happening spontaneously... until you heat it. Since there is no "hard high temperature structure" in copper, silver, gold and brass, quenching will just make it cold, not hard.



Precipitation hardening is yet another ballgame depending on diffusion and subsequent formation of crystals at the grain boundaries.


----------



## Noxx (Sep 29, 2009)

The die arrived today.

     





I can't wait to stamp my first bar.


----------



## markqf1 (Sep 29, 2009)

Sweet! 8) 

Mark


----------



## elfixx (Sep 29, 2009)

Where did you get the dies made? and what was the cost?


----------



## lazersteve (Sep 29, 2009)

Awesome die! Please do tell us where you got it!

Steve


----------



## Noxx (Sep 29, 2009)

C'mon guys, you can't force me to disclose a business secret


----------



## elfixx (Sep 29, 2009)

Business secret? lol :lol:


----------



## elfixx (Sep 30, 2009)

Isn't the purpose of this forum to share information?


----------



## glorycloud (Sep 30, 2009)

There are some things that are worth keeping to oneself. If Noxx chooses
to keep to himself his source for what he diligently pursued and found, then
more power to him! 

Find it for yourself and be proud of doing it! Don't look for a handout off someone
else's hard work and inspiration. 

Yes, the purpose of this forum IS to share information. But I add, not when it
could impact your livelyhood. You have been posting here long enough to know who Noxx
is and that he is more than a hobbyist diddling around with escrap. He has branded
a business and he put forth the effort to go first class and develop a die with his
company name on it. Perhaps, he prefers that "value add" to differentiate his
company from the rest of the "gee I have a refined gold button to sell" crowd.

There, I said it. Let's encourage each other, not demand from each other. 8)


----------



## Gold (Sep 30, 2009)

http://www.info.infinitystamps.com/


----------



## goldsilverpro (Sep 30, 2009)

I estimate that I have only shared about 40% of what I know with this forum. Many things just haven't come up yet, but I do have a short list of topics that I'll never divulge to the public. They are mainly specific, obscure, profitable processes that I have alone developed and made good money on. They are still viable and are for sale. One process is available for $1 million.

Before this forum, almost everything we now discuss openly existed only as trade secrets. As far as I'm concerned, any thing you receive is a gift. You people are blessed. Charity is charity and business is business.


----------



## oldtimmer (Sep 30, 2009)

Going along with what GSP has said, in the mid 80's I had access to several hundred pounds of scrap gold plated PC boards per month. The company that I worked for, just scrapped them out (trash can). I spent several weeks going to the library in an effort to find anything I could on how to porcess the boards to recover the gold. I do not even remember finding any of the books that are so easily recommended and can be down loaded. Some information was to disolve in AR, but not enough an how to get it back out. Found one chemistry book on how to do anaylsis using titration, but that would not work for large volumes. There were a few books on how the old miners did their analysis, part of which I had learned from my dad, but had never done it. Hear again good for a small scale, but not large scale.

My extent back then for several years was to higrade the boards that had the most plating as well as the fingers. My extent was to use Nitric acid to remove the copper base metal and leave the gold fingers. I would then melt these fingers and take them to a local group that did some refining. I then just sold the gold buttons to them and let them do the processing. Even though I got to know them very well, I could not get them to let me in on any of the information on how I could recover the gold. 

Towards the end, kept around 10 oz of the gold buttons that I had managed to salvage. I ended up selling them in the mid 90's for money to take the wife on a nice vacation.

I believe that if I would have had the information that is here on this forum, I may have done line Harold and a few others and started a small local refining business just on the scrap PC cards that the company was thtowing out in the trash.


----------



## nickvc (Oct 1, 2009)

lazersteve said:


> Looks really nice Noxx.
> 
> I just purchased a rolling mill hoping it would allow me to make smooth sheets that could be punched into discs then laser etched as 'coins'.
> 
> The mill has a very narrow opening and therefore doesn't lend itself readily to working directly from gold buttons fresh out of the furnace. They are way too thick which requires the button to be hammered thin enough to make it into the mill opening.


Could you pour your molten fine into a wire mould they are available here in the jewellery suppply shops or if you want make your own from a graphite block that might help you to start the rolling process.


----------



## Harold_V (Oct 1, 2009)

> The mill has a very narrow opening and therefore doesn't lend itself readily to working directly from gold buttons fresh out of the furnace. They are way too thick which requires the button to be hammered thin enough to make it into the mill opening.





> Could you pour your molten fine into a wire mould they are available here in the jewellery suppply shops or if you want make your own from a graphite block that might help you to start the rolling process.


That isn't the correct approach. There are molds made for the purpose. They are end poured, yielding a wide and thin ingot, which enters the rolls without effort. If you start with a wire form, you end up with a narrow, long strip of metal that won't serve the intended purpose. When rolling, very little is extruded to the sides. Material gets longer as it gets thinner, not wider. The only way you can get it wider is to roll it at a 90° angle from the previous pass. 

Harold

edit: corrected spelling


----------



## nickvc (Oct 1, 2009)

Harold said:


> That isn't the correct approach. There are molds made for the purpose. They are end poured, yielding a wide and thin ingot, which enters the rolls without effort. If you start with a wire form, you end up with a narrow, long strip of metal that won't serve the intended purpose. When rolling, very little is extruded to the sides. Material gets longer as it gets thinner, not wider. The only way you can get it wider is to roll it at a 90° angle from the previous pass.


thanks harold you got my basic idea and turned it into the correct method. The alternative is dependant on the amount of gold you wish to bar, many of the 1oz + bars are cast into a mould slightly over weight and then trimmed back to the correct weight and stamped with a hand punch, cheap but only worth the effort if you have reasonable quantities..For the pleasure of having your own stamped bars the cost i suppose is secondary even if its not a good delivery guarenteed bar most people in this business know good fine gold when they see it..


----------



## Lou (Oct 5, 2009)

goldsilverpro said:


> Before this forum, almost everything we now discuss openly existed only as trade secrets. As far as I'm concerned, any thing you receive is a gift. You people are blessed. Charity is charity and business is business.



Truer words...


----------



## Noxx (Oct 6, 2009)

Hey guys!

Here are two pics of the first bar I tried to make. I obviously need more tonnage in order to fill the die properly.

I will keep you posted.


----------



## Oz (Oct 6, 2009)

That’s looking good Noxx, you are getting there! How many tons pressure was applied with your press? Would it be possible to add a 2:1 mechanical advantage into your press to get you the rest of the way there?


----------



## Noxx (Oct 6, 2009)

It's a 12 ton press, like the one pictured at the first page.

It's a good question but I don't think this would be possible. Anyway, the press isn't made to handle 24 ton. Just imagine what would happen if this thing would break apart


----------



## Oz (Oct 6, 2009)

I just looked at your press, and yes it would be hard. A 2:1 fixture within the press would still only see 12 tons but the loading on your press would be offset and may damage it. 

Building a steel tube frame for a 12 ton hydraulic jack that uses a 2:1 or greater lever may be a simple solution though since you need little stroke at the dies. Surplus jacks are cheap.


----------



## Rhodium (Oct 7, 2009)

http://www.gregsmithequipment.com/30-Ton-Hydraulic-Shop-Press-p/iit36950.htm


----------



## Harold_V (Oct 7, 2009)

Noxx,
That's amazingly good, considering the low pressure at your disposal. 
Can I assume it is not filling the die completely? Hard to tell from my end, but surface finish certainly looks good. 

Way to go, Jean. My hat's off to you!
Harold


----------



## Anonymous (Oct 7, 2009)

Noxx, For a full fill on this ingot, you will need about 30 to 40 tons. This will sharpen and deepen the image as well as fill out the missing material at the edge of the planchet if it's not too pronounced. I suggest getting the book NUMISMATIC FORGERY by Charles M. Larson which is sold on Amazon for under $20. This book shows how to construct many things for making small runs of coins including a gravity hammer capable of striking up to both sides of a silver dollar in one drop. You won't be sorry you bought the book if you ever want to produce your own coins or ingots.


----------



## ALPHABiT (Oct 17, 2009)

I asked about 1 years ago what ton press is needed to coin up bullion bars. No answer from this forum 

I have something now, going yo see and ask directly to press producer in order to set up a small mint.

20 Ton press is quite enough to coin just a 1mm thin gold bar.
Fot a 100gr bullion bar with a thickness of 5/7mm a 120/160 tons press is suggested.
Of course this is just ti "fill" the stamp. Other ton quantities are needed to obtain a very fine angle/curve on the surface drawings (like coins).

1- Process to coin is ROLL to obtain a perfect thickness
2- Cut to obtain exact weight and stamp form
3- Red-Heat not-fine bard obtained to preserve stamps
4- Coin to fill out the stamp.

---
What i'm tring to do is pouring in a definied mold making weighted gold obtaining not fine ingots to go directly on point 4.
This is to not buy roller and cutter too!
A 200 tons press and customized stamps are very wxpensive here. Dont know there.


----------



## Anonymous (May 28, 2010)

how do you polish the gold or silver blank after heating it


----------



## qst42know (May 28, 2010)

Casting porosity may spoil your perfect weight blanks.

Video from the US mint show rolled and punched blanks being lathe trimmed to adjust the weight before being pressed into a coin.


----------

