Basic Soldering - Two wire splice
This howto will give you the basics of how to solder wires and repair a damaged electrical connector in the event a wire has broken off and it's too short for a splice.

Tools Needed:
*Wire Strippers
*Soldering Iron
*Heat Shrink Tubing, RTV, Tape Etc.


We will start with a basic solder joint; Here we have some wires, we want to join the red wire to the yellow wire perhaps to extend and make it longer. It's best to join wires of similar size as joining a smaller gauge wire to a heavier gauge wire can reduce current flow and create heat.

Next we will use our trusty wire strippers to strip back about 1/2" of the insulation covering the wires, the end of the insulation may be pulled off and discarded. Now is the time to slide a bit of heat shrink tubing on to one of the wires and slide it out of the way. Once the solder joint is complete you won't be able to get heat shrink tubing to the joint unless the other end of the wire is not connected to anything.

Next twist the ends of the wires to keep the strands nice and tight, if you leave strands poking out once you twist the joint together they could poke through electrical tape or wear through heat shrink faster.

Next lay one wire across the other, forming an X. You want to do this in the center of the bare copper as when we twist the two ends together they will lock in place and the ends will not be over the insulation.

Here we've started to twist the wires together, the red wire over, the yellow wire under, continue around the wires twisting them tightly until the ends of the wire are wrapped around the bare copper.

Now that the wires are fully twisted together the strands are tightly interlocked and we're left with about 1/2" of joint to solder overall. Next warm up your soldering iron get some solder ready!

We will start by heating the WIRE bringing it up to temprature with the tip of the soldering iron.. It is important to get the joint hot enough to melt the solder when you touch it to it, not using the tip to melt the solder and hoping it sticks.

As the joint gets hot you can touch the solder to the bare copper and it will be drawn into the joint. Cover the entire joint with solder you shouldn't have any build up of solder on the joint and no large blobs. It will soak all the way into the copper being drawn to the center and around the edges by the heat.

Here's the completed joint joined together by the solder, this joint will be very strong, and if cut in two you won't see any bare copper inside. You may now slide your heat shrink tubing in place, heat it up and complete the splice.
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