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How can I make my own solder?

Hello everyone ! here its going to be my first question at ganoksin .
I ve been thinking how to make my own solder. Gold and Silver. I used to buy from suppliers but then i thought why not make my own than buying ?
Can anyone give me a tip or formula to make Sterling silver & Gold solder ?

Thanks !
Ayca

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Buy the Complete Metalsmith by Tim McCreight and look at page 114. This is a great reference book for much of what we do. I must admit to the same curiosity and did make my own solder. It works, but I decided why bother. Just buy enough of each to cover your work needs and make it only in an emergency. Pay very close attention to Tim’s precautions about how to treat zinc in the silver solders. You can find this information in many locations and a search of the archives will result in previous discussions of this topic. Good luck…Rob

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I follow an Indonesian fellow called Kaiser Power (?) On YouTube and his recipe uses only fine silver and brass in different quantities. His skills are awesome!

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I encourage anyone who works with silver to make their own solder at least once. It is process that requires measuring skills beyond, “That about looks right.” (My preferred means of critical measurement) to create a workable solder. The best reason to buy your solder is consistency. Knowing that the H-65 you buy from your favorite vendor will have the same properties as the H-65 you buy a year later is critical. But then again experimentation is fun. Anytime you lean something it has been a good day.

Unless you are doing truly historic reproductions I would just buy it. I think the time spent making solder is time lost making a product you can sell at a price you are comfortable charging.

Rob mentioned Tim McCreight’s Complete Metalsmith book and I suggest it is required reading in any shop at any level.

Don Meixner

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You can make solder for any metal that you work with, be it gold, silver, or other alloys. Even those that contain aluminum, lead, and tin…
For the silver/copper system, there is a eutectic point of 28% by weight of copper to silver.
This is the point where the alloy composition melts at the lowest temperature. You can make solder of any composition that will melt at a lower point than sterling. DO NOT use a eutectic alloy of copper and silver since it will be off color… Zinc and silver also have composition points which are even lower in melting temperature… adding zinc is difficult to control since zinc tends to burn off at its melting point…however, a zinc silver alloy will keep it’s bright color. Zinc/Silver/Copper alloys all melt at a lower temperature any of the pure metals alone… a three metal system will have ternary points rather than a single eutectic.
I know that this seems complicated, but you can google phase diagrams for two and three metal systems…start with at a two metal composition and google the phase diagram for it…with a two metal alloy system, you can vary the composition of the alloy to precisely match it’s melting point… that way you can make solder that will melt at different temperatures…with a two metal system, the eutectic point is always the lowest melting point… in the copper/silver system, at the 28 weight% copper eutectic, the melting point will be 1430 degrees F… moving towards either more copper or more silver will increase the melting point…move towards more silver, as too much copper will cause darkening of the alloy which is your solder…the melting point of pure silver is 1763 degrees, that of sterling is 1640 degrees F… sterling is .975 weight percent silver and .025 weight percent copper.,. if you are working with sterling, you can’t add more silver to lower the melting point… you would have to add more copper…more copper will give you a lower melting point solder, but you are limited by the amount of copper than can be added due to darkening of the color…the zinc/silver system is a lot more complicated… there is a 700 degree C melting point of an alloy of about 25W% zinc… adding more zinc progressively lowers the melting point…but there is no eutectic point in this system…
you can find these composition/phase (liquid, solid) diagrams for any alloy of any two or even three metals by googling them…there are so many alloys of gold that are of bi or tri metallic composition that making gold solder is both easy and difficult… difficult because the phase diagrams become so complicated… measuring the amount of alloying metal to lower the melting point of what your wish to make into solder has to be done precisely with a very accurate scale…some diagrams make it even harder as they give the percentages of metal by atom percent… you would have to convert that into weight by multiplying it by the atomic weight, not the atomic number…
After getting tired of paying for solders, I started to make my own, using the phase diagrams.

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I make my own solders. It’s just like alloying any metal.
Just be causious that the really low melting alloys should be added last as you do not want them to burn off. Melt for eg. the silver and copper, move the flame, wait a little bit then add the zinc, then slowly heat it all again with slightly less heat. You’ll notice when it’s too hot for them as they will start smoking. Pour it into an ingot, then roll it into sheet or wire. Easy peasy.
The main thing is not to be scared about messing anything up. Try and try again. You’ll be happy that you won’t have to rely on purchasing solder. You can even come up with your own formulas.

Here is what I use:

HARD 740-787c
75% FINE SILVER, 22% PURE COPPER, 3% ZINC

MEDIUM 690-737C
70% FINE SILVER, 20% PURE COPPER, 10% ZINC

EASY 670-718C
65% FINE SILVER, 20% COPPER, 15% ZINC

EXTRA EASY 630-660C
FINE SILVER 55%, 22% ZINC, 21% PURE COPPER, 2% TIN

Good Luck!

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