Introduction: 3D Printed Wireless Lantern
This battery powered wireless charging lantern will glow for 1.5 hours on a single charge. It works with a handful of electronic parts and a USB charger. The USB cable plugs into the base, and the lamp sits on the base and charges through induction, which we'll get into later.
The lamp housing, charging base, and lens are all 3D printed on a desktop FDM printer.
This project is part of a family of wireless charging products I'm working on. A swamp cooler, bluetooth speaker, and aroma diffuser are all in the works!
Step 1: Tools + Materials
Electronic Parts
Becky Stern was kind enough to give me the following parts list for the project:
1. Universal Qi Wireless Charging Transmitter ($27) This part plugs into a USB power source and emits 3.7V power through a copper coil. This part goes inside the charging base.
2. Universal Qi Wireless Receiver Module ($15) This part receives transmitted power through a copper coil. It goes inside the lamp.
3. Micro Lipo w/MicroUSB Jack - USB LiIon/LiPoly charger ($7) This part stabilizes the power coming through the wireless receiver, ensuring that it stays at a steady 3.7V.
4. Lithium Ion Battery - 3.7v 2000mAh ($12) This is a standard rechargeable battery pack that gets is power through the Micro Lipo charger.
5. 1 Watt Cool White LED - Heatsink Mounted ($4) This is a heatsink mounted LED that is pretty bright with 3.7V. It plugs into the battery.
6. DC3-250V SPST Panel Mount Self-Locking Metal Push Button Switch 16mm ($9) This is a standard latching switch that turns the LED on and off.
Total: $74
3D Printing
Any desktop FDM printer will do. The lamp is a 5" X 5" (127mm X 127mm) cube, so any printer with a bed at least that size should work just fine.
Tools
All you need for this project is a soldering iron and a small screwdriver.
Step 2: Design
As with pretty much every project I make, I used Fusion 360 for this one. It's powerful yet easy to learn, and it's free for life if you make less than $100k per year using it.
Fusion 360 is free for students and hobbyists, and there's a ton of educational support on it. If you want to learn to 3D model the kind of work I do, I think this is the best choice on the market. Click the links below to sign up:
Check out my 3D Printing Class and my Laser Cutting Class for some extensive instruction on using Fusion to make your own awesome projects.
I played with a few different possibilities with this project. The first version was a kind of bubbly block with a lens that sort of cut diagonally through the mass. This looked good in terms of form, but I didn't see any elegant way to integrate a switch.
After working through that version, I realized that since the charging is done wirelessly, it's not necessary to have a rectangular object– the lamp can be oriented any way as long as the receiver and transmitter are within 3mm of each other. The problem with this design is that since it's a drum, the shape really lends itself to the lens being on top, which is not great for a lamp.
I settled on a more regular, modified cube design where the lens is basically 3 of the cube's sides. This gives me a protruding feature that highlights the switch and gives me enough light coverage on the sides that it will be useful on a table top.
The lens is designed to press fit into the housing with a interlocking lib around its edge. There's a cradle inside the lamp that holds the LED at a 45º angle towards the lens, and the barrier between the receiver and transmitter is kept at 3mm.
Step 3: 3D Printing
I used my Dremel Idea Builder to print the 3D printed parts. I used clear PLA for the lens and wood fiber PLA for the housings.
When it comes to 3D Printing, orientation is everything. The placement of a model on the build platform makes a huge difference when it comes to structure, but I learned something new with this project: the orientation of a model makes a huge difference in lighting effects through translucent objects.
BAD ORIENTATION
With the orientation pictured above, the top face of the lens was flat on the print bed. This saved a lot of support material, but the results were not good for a lens. The light really highlighted the interior shifts between the walls of the lens. As you can see here, the ridges are very visible around the top of the lens, and the checkerboard pattern of the top of the lens is very visible.
GOOD ORIENTATION
This orientation placed the three corners of the lens on the printer bed. This means there's a ton of support material used, but result is that the layers of the lens are concentric around the corner of it. It almost looks like an old-timey lighthouse lens. This does a good job of hiding the variations within the lens and creates a more uniform look.
Step 4: Assembly
The diagram below is an overview of the whole assembly. Basically there are two housings, the base and the lamp, that hold all the components.
Step 5: Solder LED Wires to Charger
The black and red wires soldered to the points on the board to the right connect to the wireless receiver. The black terminal at the top connects to the battery. I added the black and red wires on the top to the battery terminal leads to power the LED.
Step 6: Assemble Lamp Parts
To assembly the lamp, I hot-glue the wireless receiver pad to the recess in the bottom of the lamp housing.
The cradle has a space for the battery and one for the LED. The charger is glued to the side of the housing to keep it from blocking any light. The switch is wired in as a breaker between the LED and the charger.
To assembly the lamp, I hot-glue the wireless receiver pad to the recess in the bottom of the lamp housing.
Step 7: Assemble Charging Dock
The charging dock assembly is super simple. All you have to do is press-fit the charging coil part into the recess in the under side, add the brace to keep it in place, then screw in the circuit board to the upper level with some machine screws. The base plate screws in at the bottom to protect everything. The charging base has cutouts for the USB terminals on the circuit board, so you can use Mini USB (as shown) or standard to power it up.