People hear the word solder and many of them cringe with fear others think you need to be some long bearded wizzard or summoner of spirts to solder 2 wires together. It's actually not a hard skill to pick up. With a little practice you can be an expert well at least good enough to work on your model train layout.
First you need to make sure you have a high enough wattage soldering gun to do the job. Honestly unless you are soldering fine circuit board components go with a 200+ watt gun 250ish sounds nice to me.
Second Get a few replacement tips. The tips on a soldering gun are replaceable. Over time the tip wears away from working. You can usually buy different sizes to fit your gun and soldering job, smaller for finer work and larger for most applications. Get a variety to try out.
Quick tip...Realize it takes a bit of time for the gun to heat up, for your joint to heat up, and for all items to cool down.
Third you need a roll of solder. Go for a Rosin Core roll. They usually come in different gauge get a couple and try a few out. Finer projects to better with a finer gauge solder.
Fourth you need a soldering project. In the model train layout world your top 3 soldering tasks will be soldering wire to wire connections, rail joints, and wires on to the track for power connections. As you get more advanced and start working with a control panel or toggle switches you can add those finer jobs the list.
If you are a first timer for every scenario I would take some scrap pieces and try your technique until you are comfortable. This way you don’t make any mistakes to the real thing. The good news is if you don’t like the way a solder joint looks you can usually heat it back up and disconnect the items and start all over.
Wire to wire connections. If you can twist the ends of the wires you wish to connect together then I suggest doing it so that you do not need to hold the wires while soldering. Some jobs will not allow that to happen. In that case you have to use some sort of alligator clip, clothes pin type device to keep your wires close together. One of your hands needs to hold the gun and the other the solder so it makes it tough (not impossible) to hold the wires at the same time. Heat the gun up first until the tip easily melts your rosin core solder. Before you start to solder anything melt a little solder on to the gun’s tip. It helps conduct the heat to the application. Apply heat to the bare wires first to get their temperature up. Then slowly apply the solder if it doesn’t start to melt immediately remove it and wait a few more seconds for the area to heat up. When it’s ready it will slowly start to melt and you will see the wires soak in the solder like a sponge. If they don’t then they were not hot enough. Don’t glop the solder on it should flow nicely. Once soaked into the wires you’re done. The smaller the gauge of the wire the quicker this all happens.
Rail Joints. Remove any plastic ties right at the joint they may end up melting from the heat. You can reinstall them later. Apply the heat to one side of the rail and the solder to the other. Once everything is up to temp the solder will soak into the rail joint and be drawn toward the heat. Less is more. While the joint is still warm you can hit it with a sanding block to clean it up a bit. If you lay in too much solder you may find yourself having to file down your solder joint.
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| Tinned Wire |
Wire to rail. In this case it works like a hybrid of the two situations above. I would first “tin” the wire. Heat it up and apply a small coat of solder to the wire first. Then I would tin the area on the rail where you intend to place the wire. I find that it works best to attach power wires at rail joints. Now that both the rail and the wire is tinned apply heat to the rail when the solder starts to melt touch the tinned wire to the spot and it should rather quickly melt as well, at that point you are done, but you have to hold the wire in place long enough for the solder to cool. This could be tricky and hot to the touch. Practice makes perfect.
Quick Tip...The rules of gravity apply to solder it can drip off the solder joint like water from a faucet. Don't get caught underneath it!
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| Heat Sink Tweezers |
In all cases make sure you are in a comfortable position. Make sure that you are not under the soldering joint because sometimes hot solder tends to drip from the area. Make sure you are applying enough heat to the joint without destroying your surroundings (melting plastic ties or the insulation on the wire). In some cases you will want to use some sort of heat sink to stop the heat from traveling up your wire or rail beyond a certain point. An alligator clip will work as a heat sink or you could pick up a few heat sink tweezers to do the job. A quick tug after the joint has cooled should not be enough to seperate it. If it did you didn't get the right flow, do it again. Remember your joint and gun will remain hot well after your job is done.
Give it a shot, stop your cringing. You now have the basics needed to start soldering rail joints, and power connections on your model train layout. Practice practice practice, the more soldering joints you tackle the better at it you will become. See it wasn’t that hard.
