Rechargeable Battery Powered LED Desk Lamp

Features

• A sleek, adjustable LED desk lamp based on Volan's LED lamp design, powered by a rechargeable Lithium-ion 18650 battery
   
• Ideal for hobbies or working on fiddly electronics
   
• Gets 3 hours of battery life from a 3000mAh cell (assembled as shown)
   
• Can be powered by either a salvaged power bank or a TP4056 battery module + a 3.7v to 5v boost converter

Parts Needed

• 1 ‘Tube type’ portable power bank (the kind that comes with one 18650 cell in it, like this)
  • OR 1 18650 lithium-ion cell, 1 TP4056 charging module (with protection), 1 3.7V to 5V boost converter
• 1 5V COB LED light strip (8mm thick, can also use WS2812B or similar 5V LED strip)
• 1 Miniature rectangle rocker switch (12 x 8mm cutout)
• 2 M3 socket head shoulder machine screws - M3x4x25 (or 2 M4x30 socket cap bolts, preferably partly-threaded)
• 2 M3 nuts (or M4 if using the M4x30 bolts)
• 6 M2x5 socket cap bolts (optional)
• 6 M2 heat set inserts (up to 5mm, optional)
• Wire

Printing guidelines

• Recommended you follow the guidelines on the original model's page - parts of some models work best when printed solid. You will also need to rotate the models so that they lay flat to the print bed.
   
• Print EITHER the files in the “Salvaged power bank” folder OR the “TP4056 and boost converter” folder, depending on what you're using.
   
• Similarly, print EITHER top.stl OR top_narrow.stl depending on if you're using 2 or 3 strips. The model pictured uses top.stl.
   
• Layer height: 0.2mm
  Supports: Yes ("foot_left", “foot_left_tp4056”, "foot_right_tp4056", only the area around where the circuit boards go)
  Brim: No
  Walls: 3, but modify hinges and lower pivot to be printed solid
  Infill: 10-20%

Assembly

1. Wire up light & attach to top: Cut 3x 15cm strips from the COB LED strip and lay them side-by-side, wiring them up so that they're all connected like one long strip. At the other end, solder two 50cm wires to the strips.
   
   You can also use the original versions of the top, but I'd recommend sticking to a 3W LED or less else the battery life will be too short.
   
   top.stl will hold 3 strips side-by-side with some overlap, or will comfortably hold 2 WS2812B LED strips side-by-side.
   
   Optional: Stick some reflective material to the edges to help with light diffusion and add some heat-set inserts to the 3 holes if you wish to use the light diffuser.
    
2. Assemble upper arm: Print the outer case and colour insert files in your colour of choice. The colour inserts should be a press-fit, but a bit of glue can help. The holes that the M4 bolts go through need to be opened up since they are covered by a single layer, but don't drill them out too much!
   
   Route the long wires through one half of the outer case then clip the other half of the outer case together (no glue is needed).
   
   If using the M3 shoulder bolts: Pop an M3 nut into the nut_cap_right_OPTIONAL model, press it into the hexagon-shaped hole, and insert the shoulder bolt from the other side, through the top. This will be a very tight fit - this is intentional and gives the hinge its resistance. Screw the bolt into the nut, tighten as desired, then press-fit the nut_cap_left_OPTIONAL onto the bolt head to hide it.
   
   If using the M4 bolts: Put an M4 nut straight into the hexagon insert and insert the M4 bolt from the other side, through the top. Tighten as desired.
    
3. Assemble foot & lower pivot: Sand down the bottom of the lower pivot so that it is a very tight fit into the foot, and sand the ‘stair-step’ edges in the middle of each foot model (if you printed it in the preferred orientation on a leading edge).
   
   Add glue to the area where the lower pivot is inserted, as well as the middle edge of the foot and the little recess where the tab goes (near the rear). Press together until glued.
    
4. Assemble lamp & wire electronics: Attach the outer case to the lower pivot similar to Step 2 and glue the 18650_holder_inner into place - this is deliberately shorter than the hole it fits into to give some room for cable management (not pictured).
   
   Add the rocker switch into the foot. You will need to trim the switch tabs by ~3mm so that it fits properly - see photo.
   
   If using a salvaged power bank: Remove the large USB-A socket (but keep the micro-USB), making sure to remember which pads correspond to the +5V output and GND pins. Desolder the BATT + and - tabs. Wire up the circuit in the following way:
   
   18650 cell's + and - to the power bank's BATT + and -
   Power bank's +5V out to LED strip's +5V
   Power bank's GND out to the switch, then the switch to LED strip's GND
   
   If using a TP4056 and boost circuit:
   
   18650 cell's + and - to TP4056's BATT + and -
   TP4056's OUT + to switch, then the switch to boost circuit's IN +
   TP4056's OUT - to boost circuit's IN -
   Boost circuit's OUT + and - to LED strip's +5V and GND
   
   Now secure the circuitry in place. Note that depending on your charging circuit, some components might get hot enough to soften certain cool-melt glue sticks. If this is the case, I suggest using Gorilla Glue or some kind of epoxy to cement the circuitry in place.
   
   Optional but highly recommended: Do a better job at the gluing and cable management than me >_>
    
5. Add optional extras: Print a bottom plate to cover the electronics (add M2 heat set inserts into the foot and use M2x5 socket cap screws) and/or a light diffuser in transparent PETG (PLA might also work, but be careful of how hot the LEDs get) for a cleaner end product!