The Beginner's Guide to Soldering: LED Box

Designed in part for an assignment at Towson University, Writing for Business and Industry (ENGL 317 040)

This is an introductory soldering project designed for someone with limited experience with electronics / soldering. With no previous tools, it will cost anywhere from $10 to $30 depending on the user's location and choice of tools / parts.

Little to no previous skill is required and this is a great exercise for almost any age!

The following materials and tools will be needed:

1. Small Enclosure (OPTIONAL, I purchased a small $2 plastic box and drilled / cut holes for my LED bulb and on/off switch)
2. Soldering iron
3. Small diameter soldering core wire (1-1.5mm recommended)
4. Wire Cutter / Stripper
5. 2x AA Battery Holder
6. 2x AA Batteries
7. 2 Prong Switch
8. Raw wire, this does not have to be specific as long as it is a small diameter. I used wire from a leftover computer part.
9. 3V + LEDs.
   1. **NOTE** Because AA batteries put out 1.5V each (meaning two put out 3V combined) your LED must have a minimum power of 3V. Any less (such as 1.2V) will cause the LED to prematurely burn out and not function correctly
   2. Adafruit Diffused Color Changing 5MM LED #679 was used in this guide

Cut and strip all wire for this project. To strip a wire, select the appropriate wire gauge (by eyeballing the wire's size) and clamp down on the stripping tool while pulling the wire away. This will remove the protective plastic coating leaving bare wire that is able to bridge connections.

For this guide you will have to strip the end of both red and black wires coming from the AA Battery holder, as well as strip the ends off of a section of roughly 3 inches of raw wire.

Take the newly stripped red (power) wire from the AA battery holder and twist securely into place on one prong of the switch.

Take one stripped end of the raw wire and twist securely into place onto the other prong of the switch.

**SEE STEP 5 FOR COMPLETE WIRING DIAGRAM**

The above picture shows where to connect the ground (black) and power (red) wires to the LED. Most store bought LEDs will have two leads sticking out of them, the shorter lead is typically a ground connection.

**SEE STEP 5 FOR COMPLETE WIRING DIAGRAM**

• Black wire (ground) from battery to LED ground (shorter metal lead)
• Red wire (power) to one prong of switch
• One side of raw wire to other prong of switch. This receives power from the switch when turned on.
• Other side of raw wire to LED power (longer metal lead). This carries power from the switch to the LED when turned on.

With batteries in place and all connections secure, switch on the power. If everything is correct the LED will light up.

If the LED does not correctly light up re-check all connections.

Soldering is the practice of joining two wires or connections together with a low-melting metal allow (typically lead or tin) to create a permanent, lasting connection.

Best practice to solder two wires or a connection is the following:

1. Ensure all joining materials are clean and free of debris
2. Tightly twist wires / connection together
3. Heat soldering iron to operating temperature
4. Hold tip of soldering iron to wire or connection to heat
5. While soldering iron is heating the wire / connection, touch solder core wire to the heated iron
6. The solder will liquefy and will fill gaps / crevices, creating a permanent connection
7. Remove both solder and soldering iron
8. The solder will rapidly cool until solid, creating a permanent connection

• Check that wire is tightly twisted around connection.
• Permanently join the ground (black) wire coming from the AA battery holder to the LED ground lead.
• Refer to STEP 6 for soldering instructions

• Check that wire is tightly twisted around connection.
• Permanently join the power (red) raw wire to the LED power lead. Refer to STEP 6 for soldering instructions

• Refer to STEP 6 for soldering instructions

• Check that wire is tightly twisted around connection.
• Permanently join the power (red) raw wire from the LED power lead to one terminal on the switch
• Permanently join the power (red) AA battery holder wire to the other terminal on the switch
• Refer to STEP 6 for soldering instructions

1. Finish by testing the switch (as you did in STEP 5)
2. (Optional) Assemble the newly created battery powered LED light into the enclosure
3. Take a break and enjoy your newly created device!