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coloradotrout
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Thoughts on these?
brazing a hydraulic line
- Thread starter coloradotrout
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rScotty
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I like the Harris products, so I'd go with the bare wire Harris Safety Silv 45% that Amazon sells....and many welding shops sell Harris products as well. You will also need flux. Harris also makes a specific white flux for use with their safety silv wire.
Silver brazing is an art, but you can learn it. All the hints so far in this thread are good. You can do this...
It's just a matter of clean metal, not too much heat, use good products (Harris), and get it hot enough to flow but never so hot that the metal is scorched (forms an oxide coating). If it gets too hot just scape it clean and start over. The flux itself is painted onto the cold clean joint and can sit that way for a long time while you get everything set up. Then when you add heat, you will see that the flux will melt and flow a clear coating like frothy liquid glass. That tells you that the metal temperature is almost hot enough to add the silver wire. Sometimes I put tiny cut off pieces of the silver wire right in the flux on the joint. If they stay in position as the flux bubbles, they often become the very best indication of when to add more wire. Sometimes the little pieces are enough by themselves.
so watch your flux, the flux tells you when to add the wire. As the flux flows it cleans and coats the hot metal to protect the hot metal from forming an oxide. If the joint gets too hot, the flux will fail, all the colors will change as oxides form, and nothing will stick. Clean it all and try again,
Hot enough...but not too hot. Heat and clean metal are the secrets.
rScotty
Silver brazing is an art, but you can learn it. All the hints so far in this thread are good. You can do this...
It's just a matter of clean metal, not too much heat, use good products (Harris), and get it hot enough to flow but never so hot that the metal is scorched (forms an oxide coating). If it gets too hot just scape it clean and start over. The flux itself is painted onto the cold clean joint and can sit that way for a long time while you get everything set up. Then when you add heat, you will see that the flux will melt and flow a clear coating like frothy liquid glass. That tells you that the metal temperature is almost hot enough to add the silver wire. Sometimes I put tiny cut off pieces of the silver wire right in the flux on the joint. If they stay in position as the flux bubbles, they often become the very best indication of when to add more wire. Sometimes the little pieces are enough by themselves.
so watch your flux, the flux tells you when to add the wire. As the flux flows it cleans and coats the hot metal to protect the hot metal from forming an oxide. If the joint gets too hot, the flux will fail, all the colors will change as oxides form, and nothing will stick. Clean it all and try again,
Hot enough...but not too hot. Heat and clean metal are the secrets.
rScotty
etpm
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When silver soldering/brazing the key to successful soldering is to heat the metal fast and let the metal melt the solder. The purpose of the flux it to clean the metal and keep oxygen away from the area to be soldered. Oxygen is kept away by the flux absorbing the oxygen. If the flux is kept hot too long it will absorb all the oxygen it can and then oxygen will get to the hot metal and oxidize it. Then the only fix is to remove ALL the burned flux and then sand or file the metal to remove all the oxides. If the metal is heated too slowly then the flux will be burned. So heat fast, don't heat the solder with the torch, don't let the torch flame touch the solder, and let the metal melt the solder. Just like when soldering copper pipe with plumbing solder.
Eric
Eric