Trying to solder PE brass. I use flux (the paste type), a 40-watt soldering iron, and solder (not sure which type). I apply the flux, heat the part until the flux liquifies and sizzles and then apply the solder. The solder either doesn’t melt or, if it does melt, it just forms tiny balls and doesn’t flow into the joint. This is maddening!!
What am I doing wrong??
Vic
Take a look at this video.
A fellow club member uses a fiberglass eraser first then a contact soldering iron.
I may be the odd man out here- many disagree with me. But I do not use acid core flux with brass. No need to, brass solders so well you can almost get away with no flux at all. However, I use electronics solder, which uses rosin flux encapsulated inside the solder.
The problem seems to be evident in the solder not melting well. It sounds like you are not getting the piece hot enough. If it is hot enough the solder will melt and flow readily. A 40 watt iron should do the job. Are you keeping it clean? One objection I have to acid flux is that it is hard on iron tips. Your tip should be shiny, bare metal.
To get part hot enough, you need to use a little solder to act as a heat transfer liquid. While holding the iron on the part, put a slight amount of solder in the area where the tip and part touch. Solder should melt, and wick into the area between part and tip, allowing the part to get hot.
You didn’t say what solder you are using. For PE parts use either 1/32 or at most 1/16 inch diameter solder.
You’re not the odd man out, I’ve always used rosin core solder for brass, and copper. The flux is already included in the metal. What type of solder is also a huge factor. Use 60/40 solder with a 40 - 45 watt soldering iron. As Don said before me - you want to maintain a clean bare metal tip. Once it turns black, it’s all over! [blndfld] It saps all the heat from the workpiece. You want to use 220 grit sandpaper to remove it so it’s shiny.
Lay the iron on the metal long enough to get hot, then touch the solder against the metal - not the iron. It will of course, get on the iron a little, but too much will burn the soldering flux, and wick (draw) it away from the part(s) you want to join. I even use solder to seal the ends of aluminum tubing for special projects. The trick is patience - you can never have too much of it! I’ve had to redo a few of these several times to get it right! If all else fails, use a small drop of superglue. This is what I use as a binder for difficult to join, small parts that surface tension of the solder wants to fall away from. Solder right on top of the glue while it’s wet, you’ll get a stronger, and more compliant join between the two surfaces.
The glue acts as both a catalyst, and a binder that causes capilary action to draw the solder into it to break the surface tension. This should also give you a more even weld between the two mating surfaces. If you really want to ensure that this will never break apart - sand your brass with 500, or 600 grit sandpaper to give the surfaces a little “bite” so that solder can stick easier, even if you have to use the glue trick. Just remember to not breathe the fumes from this in. Don’t worry about glue getting onto the iron tip, superglue hates hot soldering irons, and tends to stay on the surface it was originally applied to, which should be a lot cooler, once soldered together.
~ Cobra Chris
Thanks for the help guys!! Looking forward to getting back into it with the proper techniques. Thanks again!!