The Mysteries of Soldering

Posted: Wed Mar 12, 2008 1:01 pm     Post subject: The Mysteries of Soldering

Soldering is a world unto itself, and I thought it was simple...
There's hard solder, soft solder; there's lead solder and silver solder; there's fluxing and tinning; there's irons and torches. Maybe I should just use the JB Weld...
If you have experience hard soldering, please give me a few words on it. All I want to do is solder a bezel ring back on to its hinge, but I don't want to discolor to bezel by overheating it. I thought about drilling two tiny holes and joining the bezel and hinge with two tiny screws, but I think I should solder it.
When I take two pieces of brass tubing to solder together as an experiment, I paint some flux on them wire them together, and put the torch on. I use a simple propane torch. I hold the flame on the place to be joined. After the flux melts and the metal starts changing color, I figure it's time to apply the solder, but when I do, one of two things happens: the solder will stick but not melt OR it will melt and just run right off the work, not really adhering to the metal, much less seeping into the joint! What am I doing wrong? Any thoughts would be very helpful.

Posted: Thu Mar 13, 2008 12:18 pm     Post subject: Soldering

There could be a number of reasons for poor solder joints...wrong solder and/or flux for the job; coating on the materials to be soldered so that solder and flux won't flow properly; or insufficient heat at the soldering points, etc, etc.

Soldering a hinge/bezel combination requires a light touch. Certainly using a propane torch is overkill. A small electric soldering iron is better suited to the job. For similar type jobs I use an Ungar soldering pencil. These are available with different size tips and element wattages. You can use wire solder and paste flux (the same as is used to solder copper plumbing). The parts to soldered should be clean. The secret is to apply just enough solder and flux to do the job, without overheating the brass and discoloring it. At the same time you are trying to conceal the repair once the bezel is closed so use solder sparingly.

Posted: Thu Mar 13, 2008 6:28 pm     Post subject:

My technique is to use a copper iron as i was taught many years ago...ahem.

As above clean well with emery paper or file etc - most important.
Use a propane torch or similar to heat the copper iron - about at least 1 inch square diameter. This will take a while until it glows green in colour. Brush end with wire brush and tin it.
Get solder - electrical with flux in will do- ready. I also use an added flux to make sure it runs well. Dip the solder into the flux.
Apply the iron to the hinge joint and wait for it to heat up-should take about 10 - 20 seconds.
Dab the bezel joint with the flux on the end of the solder and the solder from the iron will run.
Job done with no overheating or discolouring of the metal. I've done this many times.