Soldering the Switch and Power Plug
These are some recommended tools for completing this section:
- Soldering station
- Wire strippers/cutters
- Small flat head screwdriver
- Pliers
- Solder
If you have never soldered electrical connections together before, watch this video to learn how it's done on the RoadRunner. This video is for the RoadRunner 4.1, but it is still relevant. The same process will be used on the RoadRunner 5.
It is strongly recommended to watch the video before doing this section.
These are the pieces that will be soldered.
The DC power plug consists of two wires. The red wire (positive) will be soldered to the red wire of the battery. Positive to positive. The black wire (negative/ground) will be soldered to the black wire of the battery with the switch in between this connection.
Cut the black wire about 4 inches from the end. The third image shows where the switch will go. The switch will physically interrupt the connection which will disconnect the battery from the Arduino.
Don't solder to the switch just yet, the switch will need to be inserted into the frame first.
Battery Warning:
When soldering to the battery connectors, make sure to only work on one wire at a time and leave the other wire in the connector. Taking both wires out at the same time could result in a short which can cause the battery to leak or be permanently damaged.
Look inside the battery connector. There will be two small tabs that are holding the wires inside the connector.
To remove a wire, stick a small flat head screwdriver into the connector and bend the tabs inward.
It is now time to solder the power plug positive wire to the battery positive wire. It is strongly recommended that you watch the video before soldering.
To join the two wire together, hold the wires so that they are touching. Don't hold the wires with your hands, the wires will get very hot.
Heat the connector and the wire at the same time and apply solder to the connection. When the solder melts, watch and make sure it sticks to both connection points. Let the solder cool for a bit
Use the small screwdriver to bend the tabs on the connector so that it is shaped like an arrowhead. Press it back into the plastic connector piece and make sure it is firmly seated.
Next, follow the same procedure to remove the negative terminal of the battery and solder the short section of wire to the terminal.Reinsert the negative terminal into the plastic connector once it has been soldered.
The switch hole is a press fit design. Once the switch is inserted, it will become very difficult to remove without damaging the frame. It is best to solder the power plug wires onto the switch after it is inserted. If the wires are soldered to the switch before the switch is inserted into the frame, they will have to be desoldered and resoldered to fix it.
Line the switch up with the hole (not as shown in the picture) and press straight down with a good amount of force. The switch should snap into place.
This should be the current state of the power assembly. It is now time splice (join) the switch in between the section of cut wire.
Before soldering the wires, add a small section of heatshrink to each wire.
The switch terminals and wire ends in the above picture have been tinned to make soldering to them easier.
Tinning the connections means adding a small amount of solder to each one before joining them together. Tinning is explained in the tutorial video. Once they are tinned, hold the wire onto the terminal and heat the solder until it is molten. The solder should join the two connections.
Slide the heatshrink over the exposed joint and shrink it using a heat source (heat gun, lighter, soldering iron set to low heat).
The last step of this section is to attach the battery to the bottom of the frame. Use a large piece of velcro attached to each piece. The fuzzy velcro goes on the battery, and the stiff velcro goes on the frame. You can manage the cables any way you see fit. Make sure the charging port on the battery is accessible so that it is easier to plug into the charger.
