Hello this is a DJI Spark named Little Big Red Beard. He is in rough shape he was headed for the trash before I rescued him. LBRB’s last crash resulted in a broken leg and who knows what else.
This was my tedious journey to keep Little Big Red Beard from being recycled.
Step 1: Lets Identify Everything That Is Wrong Shall We
Well obviously he’s got a broken leg and it looks like 2 of the wires are also detached from the circuit boarding the bottom of the motor. Removing the top cover (6 screws on the bottom) reveals more issues inside. One of the antenna cable connector that is supposed to be attached to the main circuit board is missing. The other is loose on one side, and the GPS ribbon cable is also not connected on one side. I have to remove the GPS module to reattach it. looking closely at the main board I see that one soldered connector for the antenna is broke off completely. After using the googler it looks like i can cut the wire and solder the two wires directly to the board. Whats the worse thing that could happen?
Step 2: How to Fix These Issues?
GPS chip is easy to remove by removing the top 4 screws. I reconnected the cable to the main board and put a dot of hot glue on both sides to hold it in place. The antennas were a bit trickier. I cut of the connector on the antenna wire and carefully separated the center wire from the outer braided wire. The center wire is soldered to the tiny trace in the top center of where the connector was and the braided part (Ground) to the left or right side. This took forever and i had to file my soldering iron tip in order to get the point fine enough to do so but it is possible. Be patient!! The wire will break for like no reason so bend everything to how it will sit before you solder. Once attached I used epoxy to keep the wires held in place. The glue you use cant be conductive AT ALL or it will cause interference. Its looks ugly as hell but it works and that is what matters to me. To Test ensure that everything is plugged in and power on connect to the drone and start walking. Phone signal is short range anyway but I made it 600 yards before i was satisfied.
Step 3: Motor / Body Work
The wires are ran in the leg of the drone in-line with how they connect to the board so just line them up and reattach them. I removed the old solder and broken wire bits to make sure nothing shorted out. Then strip and tin the wires and seated them in there grooves. Now that the wires are connected I put in a battery and checked if everything worked and it did.
To reattach the plastic bits I cleaned up the break joint with a little sand paper and rubbing alcohol. A small amount of super glue on the very inside edge (just enough to hold it in place while you work). My experience is glue is just not enough for stuff like this, it will just break easily in the future. With the plastic welder warmed up I cut a small piece of reinforcement mesh and bent it in the shape of the joint. Using a big paper clip to hold the outer edge while I heat the mesh at the break point. With the plastic welding iron press the mesh into the plastic, as soon as you remove the iron apply pressure with tweeters to keep the mesh in the plastic while it cools. After the mesh is below the surface I covered the area with new plastic using the welding iron. After everything cools file and sandpaper by hand to its original shape. I covered the area with 2 part epoxy for a smooth finish and I sanded the epoxy to remove extra and clean up runs. This gave me strong smooth leg that the attachments still fit on.
Step 4: The Finishing Touch
Final test flight (in the garage because its raining outside) and were good. Reassemble, clean up, and dress up. LBRB flys, hover is stable, range of the WIFI is great, and everything looks good on the app. I am so excited this worked. This was not quick, take your time. I tested parts after every step to make sure that what i did worked. Total time your looking at 2-3 hours (add 1 more hour for sanding) depending experience level. But Little Big Red Beard is back in action.
Please let me know if this was helpful in the comments. I like hearing what you guys think, and remember you can do anything.