Broken Flashlight Repair

My favourite, old LED flashlight fell apart when I shook it to remove something that had stuck to its magnetic end. Where it broke, its clear tube pulled out of its aluminum handle base, and two wires broke as a result, so I had to solder the wires back to their correct places and glue and seal the clear tube back into its metal body. Repairing the wires: First, I had to determine where the wires broke away, 3 wires were protruding out of the handle base with one wire still being attached to the printed circuit board (PCB) in the clear tube section, one wire a full length but its far end not attached, and one wire only half length but also unattached at the far end. This made it easy because all three wires would likely have been the same length originally so the long, loose wire must have attached to the PCB in the clear tube, and the short length wire must have attached to the short, loose wire coming out of the handle. Inspecting the end of the PCB that is visible in the clear tube showed a solder lump that looked like a wire attachment point so that is where it must get soldered back to. I soldered the two short green and yellow wires together. I slipped a piece of heat-shrink tubing over one wire as far up the wire as possible. I coated both wire ends with solder so the wires would easily stick together in the next step. I soldered the wire ends together (it only takes a few seconds of heat as you just hold the wires so they are touching each other and then touch the soldering iron tip to them until you see the solder melt, then remove the tip while still holding the wires together and the solder solidifies). I slipped the heat-shrink tube up the wire until it covered the joint and then heated the tube. It shrank in diameter by about half to grip the wire and to prevent accidental short circuits. Next, I soldered the long red wire to the end of the PCB in the clear tube. I coated the long wire’s end with fresh solder, then held the wire’s end onto the old solder lump on the PCB. I then angled the soldering iron’s tip into the end of the tube until it contacted the old solder lump and wire, and after a few seconds when the solder melted, I removed the iron’s tip while continuing to hold the wire in place until the solder solidified. I tested the wire repair by putting in batteries and making sure the flashlight now works. It did, and so now I moved on to gluing the body back together. Repairing the body: I gently scraped the old glue off the handle and clear tube. Once I could dry fit them back together easily, I was ready to move on to gluing it back together. I figured out where I wanted the on/off switch relative to where the LEDs will shine (not into my face) and then dry fitted the parts and put a piece of masking tape over the seam, then cut the tape at the seam so I can use it to align the two halves when I slide them together when gluing. I chose room temperature vulcanizing (RTV) silicone sealant to glue the body together, as it will seal out water and yet be strong enough with the large surface area it has to bond to. The 1.5 inch-diameter tube enters the handle by 0.5 inches, and is a snug fit, so with all that area I do not need a strong adhesive to hold it solidly. Also, if for some reason I need to separate the two parts in the future (to repair a switch, etc), it should still be possible to get them apart if I pull and twist with enough force. I sparingly applied the RTV silicone sealant into the aluminum handle’s opening, and then liberally applied it to the outside diameter of the clear tube. I then pressed the two parts together using the masking tape pieces as an alignment guide. The RTV silicone sealant squeezed mostly out onto the clear tube, so it was easy to clean off (this is why I applied it liberally to the tube only). I then removed the tape and then ran my finger around the outside diameter of the joint to smooth out the sealant into a small bead and ensure no gaps were visible for water to get into. I left it 48 hours to cure. That's it. The repair is finished and it saved me from having to buy a new flashlight as good as this one.