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DISCOLORATION OF BRASS WHEN SOLDERING

WHEN SOLDERING .032 BRASS TO .032 BRASS USING A 60/40 FLUX CORE SOLDER ALONG WITH STAY CLEAN SOLDERING FLUX THE BRIGHT BRASS FINISH WILL DISCOLOR TO A PATCHY REDDISH COPPER COLOR IS IT POSSIBLE TO GET THE BRASS TO SOLDER WITHOUT THE DISCOLORATION? WE USE A HIGH WATTAGE SOLDERING IRON.

THANK YOU,

ROBERT HERMAN
- PORT ORANGE, FLORIDA
2003

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December 27, 2008

Sounds like you are burning or etching away the zinc in the alloy.

Check with a brass supplier regarding the proper solder and temperature to solder this material as it sounds like it is possibly getting too hot.

A protective coating over the brass around the joint may help, as may heat sinking the metal nearest the joint. Kool Jewel, a jeweler's compound for protecting stones and fittings near solder joins is one possibility.

Charles M. Barnard
- Menomonie, Wisconsin

Is there a way to remove the copper that has come to the surface after soldering brass?

Jann Greenland
- Little Rock, Arkansas
July 31, 2009

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Hi. I'm not sure if it's practical to actually remove the excess copper, but it it possible to bright dip the brass to get it back to a nice color. Many types of bright dip are available, but the most popular is probably the proprietary sulfuric acid + hydrogen peroxide formulations. I'd suggest asking a plating shop to do a sample, as that way you won't have to learn everything all at the same time :-)

Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 6, 2011