Introduction: The Ultimate Wire Soldering Guide for Beginners

By 4DIYers
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Video tutorial on how to properly solder wire. There are different types of soldering tools you can purchase, the first is a soldering iron which I am using here, next there is a soldering gun, and finally a soldering station. There are two different types of solder used in electronic soldering. Rosin core solder does have the chemical to clean the connection which is rosin and is a just when soldering wiring or electronics. Rosin is the flux. Do not use an acid based flux such as what is found in plumbing applications as this will cause the connection to corrode and eventually fail. Lead solder tends to be a little easier to work with, has a lower melting point but is hazardous to both your health and the environment. Due to the change in environmental regulations, lead free solder is becoming more common. It does have a higher melting point, but it about to withstand higher heat applications and is more environmentally friendly.

Tools/Supplies Needed:

  • solder iron
  • solder
  • wire strippers
  • safety glasses
  • contact cleaner or rubbing alcohol
  • toothbrush
  • wire
  • pliers
  • knife

Step 1: Getting Started

Always clean the soldering iron’s tip before and after usage. This is done by heating the tip, then rubbing it on a wet sponge. If this isn’t done, this will cause heat transfer problems along with introducing impurities into the soldered joint.

Once the tip has been cleaned, now we must tin it. This helps prolong the life and promotes heat transfer to the connection.

Do not cut a length of solder, simply unroll a couple feet so we have plenty to work with. Cutting the length can be wasteful, whatever we don’t use can be rolled up.

Clean wire is extremely important as this can cause adhesion issues. If the wire was corroded, it’s best to cut that back and find a clean section to work with. Stranded wire can be especially hard to clean than compared to solid wire. Rosin flux can be used besides Rosin core solder to maximize cleaning, contact cleaner can also be used or rubbing alcohol with a toothbrush. The rosin core in the solder will also clean a connection if it’s not overly dirty. When the connection is heated, the rosin will eventually burn off.

Step 2: Connection #1

Similar type of technique compared to a Western Union Splice. Strip the insulation back roughly 3/4” of an inch, spread the strands of wire, then insert the strands into each other. Continue to twists the strands around each end, somewhat interlocking the connection. Now solder the joint, ensure the soldering iron is hot, the tip is tinned and then apply it to the connection. Wait a moment until the wire is hot enough and then apply the solder. Do not apply an excessive amount of solder and ensure you do not damage the existing insulation.

Step 3: Connection #2

The Western Union Splice, also known as the Lineman’s Splice is an extremely strong connection, sometimes stronger than the wire itself when done correctly. Strip the insulation the wire back about a 3/4” of an inch and then twist the strands of wire together. Cross each exposed wire about 90 degrees and twist around the opposite end. We are looking for about five times of wrap, if required use pliers to push the tip of the wire down so it doesn’t create a sharp edge which can cause issues such as poking through the insulation. Ensure the tip of the soldering iron is hot, apply it to the joint, allow it to heat up, and then apply the solder.

Step 4: Connection #3

A "T" or Tap splice connection which is intended to attach a new wire to an existing length of wire without cutting into it. Strip the section of wire you want to intercept, here I am using a knife, but be careful not to cut existing strands of wire. Remove about a 3/4” of an inch of insulation back on both pieces of wire. If you are working with solid wire, intercept the new wire at 90 degrees and then wrap it tightly around the existing wire. If you are working with stranded wire, the wire can be separated into two sections if you desire, but isn’t required. First wrap going in the opposite direction once, then go back and continue to wrap the other way. Depending which way the wire will be running will depend on it’s orientation, you’re looking at about five times of wrap. Use pliers to push the tip of the wire down so it doesn’t create a sharp edge which can cause issues such as poking through the insulation. Make sure the tip of the soldering iron is tinned, heat up the joint and then apply solder to the connection.

Step 5: ​Connection #4

A rat tail soldered joint which is used to connect two pieces of wire side by side. Strip the insulation the wire back roughly 3/4” of an inch again, place both wires side by side and then twist together. We are looking for about five times of wrap. Then apply solder to the connection.