Jewelers use flux during soldering to prevent oxidation and help the solder flow. Learn about different types of flux and which products work best.
1 Minute Read
After pickling the item, coat/dip it first in a boric acid flux that protects the entire piece from oxidation and fire scale (heavy oxidation that forms on the jewelry from copper in the metal). Fire scale is very difficult to remove.
60% boric acid and 40% denatured alcohol yields an excellent and inexpensive flux. Add the boric acid to the alcohol until it stops dissolving and forms a thin paste. Dip the entire item into the solution, then dry it with gentle heat from your torch. Do this three or four times before soldering.
You can find boric acid and denatured alcohol at your grocery store or online.
Now, you need a flux at the solder joint to help melt the solder without oxidation. This is called flow flux. Batterns and Handy Flux are the top choices. You can also use boric acid and water.
Use enough flux to protect the joints from oxidation, but not so much that it prevents the solder from flowing. Flux will bubble when the torch first touches it, and too much flux will create a lot of bubbles. The bubbling may cause your solder piece to shift, so preheat the flux a bit and then add the solder piece.
Flux dries out easily. Keep enough in a small vial to complete the job. Store the rest in an airtight container.
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After pickling the item, coat/dip it first in a boric acid flux that protects the entire piece from oxidation and fire scale (heavy oxidation that forms on the jewelry from copper in the metal). Fire scale is very difficult to remove.
60% boric acid and 40% denatured alcohol yields an excellent and inexpensive flux. Add the boric acid to the alcohol until it stops dissolving and forms a thin paste. Dip the entire item into the solution, then dry it with gentle heat from your torch. Do this three or four times before soldering.
You can find boric acid and denatured alcohol at your grocery store or online.
Now, you need a flux at the solder joint to help melt the solder without oxidation. This is called flow flux. Batterns and Handy Flux are the top choices. You can also use boric acid and water.
Use enough flux to protect the joints from oxidation, but not so much that it prevents the solder from flowing. Flux will bubble when the torch first touches it, and too much flux will create a lot of bubbles. The bubbling may cause your solder piece to shift, so preheat the flux a bit and then add the solder piece.
Flux dries out easily. Keep enough in a small vial to complete the job. Store the rest in an airtight container.
Budget
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