Hi,

Just wondering what you might recommend for soldering light gauge brass car kits? I have an AB 100W resistance soldering station, but I have been told I risk warping the thin brass. I'm considering using Rickety Rails low temp solder or H&N Flux with their solder. I have a Weller 35W pencil iron, but I'm looking at upgrading that to on of their digitally controlled units. Thoughts?

Thanks, Lou

-- Lou Nigro (loumickie@verizon.net), February 20, 2005

Answers

Lou,

I have never soldered together any light gauge brass car kits. So what you are getting here are simply my thoughts. If someone else with experience tells you something different, go with their advice. My only experience with soldering sheets are kits made of tin-plated steel.

When welding stainless steel, warping sheets is a problem. I have never soldered anything and had it warp on me. I don't THINK that warpage will be a problem for you.

In soldering together my sheets for the building kits I have made, I did not use my resistance soldering station. I found a gun did a good job of making a soldered seam. Resistance stations aren't good for making seam joints because if you move the tips, you will arc them - which causes them to get dirty and stop working. If you want to do spot solder joints, unless I am wrong about the warping, the resistance soldering station should do a good job for you. Just dial it up for the amount of power you find you need.

I definitely recommend liquid flux for any application where you want to make a solder joint in the shortest amount of time. Time is saved because you are not liquifying a solid flux. I definitely recommend the H&N flux. That stuff works great. Just be sure to use a solid solder that does not have any flux already in it.

Also, if you want to form a joint in the shortest amount of time, do not use any solders which advertise themselves as silver-bearing. The more silver that is in a solder, the more heat it takes to melt it. A solder will say if it has any silver in it. Most do not. Also for a quick joint, use traditional 60/40 tin/lead solder. The lead free solders take longer to melt.

One caution about using your resistance station to assemble cars. If you have to attach fine brass wire as railings and plumbing, be careful. Don't use your resistance iron in such a way that it passes its current through the brass wire. You could melt the wire.

If you are happy with your 35W pencil, I'd keep using it. That's what I use when I use a pencil. I have never found a need for the fancy soldering stations. If you want lower power sometimes, but another lower wattage pencil. I have 15W, 25W, and 35W pencils. They still are far cheaper than a station. For when you need variable power higher than 35W, you have your resistance station.

-- Allan Gartner (wire4dcc_admin@comcast.net), February 20, 2005.