goldnugget77
Well-known member
when I researched this on the internet spelter
I got this
http://en.wikipedia.org/wiki/Spelter
can someone explain this
Thanks
I got this
http://en.wikipedia.org/wiki/Spelter
can someone explain this
Thanks
spelter
- Thread starter goldnugget77
- Start date
Help Support Gold Refining Forum:
Not sure what it is you want explained. Looks like it is just saying that "spelter" is another word for zinc.
Were you thinking "Smelter"?
Were you thinking "Smelter"?
goldnugget77
Well-known member
Hi Platdigger
I am looking for a formula for making silver solder
In an old book I found a formula that uses
Fine Silver
Copper
Spelter
I want to make silver solder to sell to jewelers for bonding 2 pieces of metals
I am looking for a formula for making silver solder
In an old book I found a formula that uses
Fine Silver
Copper
Spelter
I want to make silver solder to sell to jewelers for bonding 2 pieces of metals
Spelter is zinc, but alloying is a little more difficult than just adding copper zinc and silver to a crucible. The zinc in a melt will burn off at high temperatures, because of this the alloying industry commonly mixes the zinc and copper together first and granulates it (pours it into small sized shot) and adds that to the silver.
The reason being the zinc doesn't burn off as fast when it's alloyed with the copper. Here's why, zinc melts at 420 C, copper melts at 1083 C, and Brass, which is copper and zinc mixed melts between 900 and 940 degrees C. Silver melts at 962 C so since the melting points of the silver and the brass (copper zinc mix) are close you will loose less zinc from the alloy on melting and keep the actual alloy close to its intended percentages.
The amount of zinc lost in alloying the copper and zinc is a well guarded secret but a little experimentation and you could get it right. An other critical point is the temperature of your melter, too high and it will mess up. Today most alloyers use a pyrometer to get the temperature right but in the old days they judged temperature by the color of the glow of the melter.
The reason being the zinc doesn't burn off as fast when it's alloyed with the copper. Here's why, zinc melts at 420 C, copper melts at 1083 C, and Brass, which is copper and zinc mixed melts between 900 and 940 degrees C. Silver melts at 962 C so since the melting points of the silver and the brass (copper zinc mix) are close you will loose less zinc from the alloy on melting and keep the actual alloy close to its intended percentages.
The amount of zinc lost in alloying the copper and zinc is a well guarded secret but a little experimentation and you could get it right. An other critical point is the temperature of your melter, too high and it will mess up. Today most alloyers use a pyrometer to get the temperature right but in the old days they judged temperature by the color of the glow of the melter.
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Consider that the industry that manufactures such items often has equipment that operates in an inert atmosphere, or a vacuum. That insures that the end product is not oxidized.
The purpose of zinc in solder is often to behave as a sacrificial element, preventing the oxidation of copper. and silver. A person attempting to make solder may encounter problems that yield a less than acceptable product.
I'd give serious consideration before venturing forth on a concept such as this, for you are highly unlikely to be competitive with industry, not only cost wise, but quality wise. A solder that yields problems would likely cost you customers. I know that was true of providing inferior quality gold. One of my best advertising methods was a friend that refined, but very poorly. He steered more business my way through his inferior quality than I could have hoped for in my wildest imagination.
Harold
edit: damn, I wish I hadn't said that. Silver is difficult to oxidize. That's not an issue in this case.
The purpose of zinc in solder is often to behave as a sacrificial element, preventing the oxidation of copper. and silver. A person attempting to make solder may encounter problems that yield a less than acceptable product.
I'd give serious consideration before venturing forth on a concept such as this, for you are highly unlikely to be competitive with industry, not only cost wise, but quality wise. A solder that yields problems would likely cost you customers. I know that was true of providing inferior quality gold. One of my best advertising methods was a friend that refined, but very poorly. He steered more business my way through his inferior quality than I could have hoped for in my wildest imagination.
Harold
edit: damn, I wish I hadn't said that. Silver is difficult to oxidize. That's not an issue in this case.
Modern alloys are often made in vacuum but if you can control the temperature it can be made effectively in air. With the difficulty most members are having selling their fine gold and silver the potential of making it into a product that jewelers can use may work for some. Even if you sell it at spot gold price for the gold contained, it won't cost as much as it does to sell small quantities to a refiner who has to charge for the assay and re-refining costs.
We should attempt to compile all of the wisdom on this board to come up with a few basic alloys that may enable members to sell their gold for a decent price.
I can take you into 4 or 5 small refiners who make their own alloy for this purpose, some use induction and some gas. If you have a buyer it can work for you, but Harold is right, you have to get it right so you don't lose customers.
We should attempt to compile all of the wisdom on this board to come up with a few basic alloys that may enable members to sell their gold for a decent price.
I can take you into 4 or 5 small refiners who make their own alloy for this purpose, some use induction and some gas. If you have a buyer it can work for you, but Harold is right, you have to get it right so you don't lose customers.
goldnugget77
Well-known member
Hi Harold!
I have seen casting being done with a machine similar to this one
UltraVac Casting Machine
http://www.shorinternational.com/CastingMachine.htm
The outcome of the result was not always consistent.
Not always very good.
I am guessing that the the temperature of the metal when it was poured into the flask was not always the same.
The person casting didn't know exactly what he was doing
Sometimes too hot and sometimes not hot enough.
Harold
You are right about being cautious with the quality of the finished product.
You can never take customers for granted.
At McDonalds
Even when it is a cup of coffee that they sell
They treat the customer like a king
Hi 4metals
This would be a be asset for those who are dealing with jewelers.
I have seen casting being done with a machine similar to this one
UltraVac Casting Machine
http://www.shorinternational.com/CastingMachine.htm
The outcome of the result was not always consistent.
Not always very good.
I am guessing that the the temperature of the metal when it was poured into the flask was not always the same.
The person casting didn't know exactly what he was doing
Sometimes too hot and sometimes not hot enough.
Harold
You are right about being cautious with the quality of the finished product.
You can never take customers for granted.
At McDonalds
Even when it is a cup of coffee that they sell
They treat the customer like a king
Hi 4metals
This would be a be asset for those who are dealing with jewelers.
That link is for induction melting of assemblies as in brazing 2 pieces together or annealing / heat treating pieces already assembled without effecting the temper of the entire piece.
When you make alloy you have to bring the entire crucible up to the temperature needed to melt the metal. Of course induction does that as well but that isn't what the link was about.
When you make alloy you have to bring the entire crucible up to the temperature needed to melt the metal. Of course induction does that as well but that isn't what the link was about.
