Tiny Wooden Lamp

A tiny wooden lamp which looks pleasant and can create an individual lighting mood. It can be built in various sizes and wood species. To make it unobtrusive, it is completely controlled via touch sensors inside the base and has no additional switches. You just need to connect it with a usb cable.

The main idea was to see if I can use molten hot glue to create a diffusor for the LEDs. It worked out extremely well on the prototype, so I built this lamp.

Main features are:

• Completely controllable without mechanical switches
• Adequate brightness and also lower light modes
• Lightweight
• Fun to watch

Tools:

• Saw
• Wood glue
• Hot glue gun with glue
• Soldering iron
• Drill
• PC/Laptop to program the arduino
• FTDI programming adapter or arduino UNO to program the arduino
• Router (alternative possible when not available)
• Sanding paper / Electric sander
• Clamps for bending the wood
• Some pans or pots to bend the wood

Materials:

• Thin plywood or other wood (3-4mm)
• Thick Plywood or other wood (15-20mm)
• Arduino nano / pro mini
• SK6812 LED strip with 8 LEDs
• Some Cables
• micro usb connector or cut usb cable
• Copper foil or Aluminium foil

The base consists of a wooden disk. I sawed mine with a jigsaw and smoothed the edges with sand paper. On one side it should be flattened to attach the top of the lamp.

To put all the technical part inside, I used my router to carve out the disk. Get out as much as possible since you want the sensor pads to work through the wood. Having a thick layer of wood makes it more inaccurate. I haven't tried it, but you probably can also create a wooden ring and glue a thin disk of wood on it.

Make a hole in the flattened part to insert the usb connector inside I used a drill for this. Instead of using the usb connector you can also cut a usb cable and directly solder it inside. This just needs a hole which is big enough for the cable.

The sensor pads are the first part to put inside. I used self-adhesive copper foil. The foil can be directly soldered and does not need additional glue. It should also be possible to use tin foil, but it is not (easily) solderable, so you need to attach your wires differently e.g. with tape. Be sure to have a good contact.

When you are using an Arduino Nano, you don't need this step. The Arduino Nano has a usb connector for power and programming.

For the Arduino Pro Mini you need to add an programming adapter and the power supply.

Diectly solder the usb socket to the VCC and GND pins of the Arduino. If you don't want to use a usb socket, you can also cut a usb cable and directly solder it to the Arduino. The power lines are red (VCC) and black (GND).

The programming adapter can be used to connect to an USB FDTI adapter or Arduino UNO as programmer. The wiring fits to mine, but you may have another one, so be careful to not mix the wiring up. See the instructables below for details:

For FDTI see this Instructable:

https://www.instructables.com/Program-Arduino-Pro-...

For using an Arduino UNO as programming adapter see:

https://www.instructables.com/How-to-Program-Ardui...

When programming, the usb socket must be unplugged. The power comes from the programmer.

The electronics consist of the following parts:

• Arduino board
• SK6812 LED strip
• Wires.
• 3x 10Mohm resistors
• Micro USB adapter for Arduino pro mini
• Prgroamming adapter for Arduino pro mini

Solder the resistors directly to the sensor pads. All of them are connected on the side which is not soldered to the sensor pads and connected to pin 8. Additional wires are soldered to the pads and connected to pins 2,4,6

Solder the wires from the led strip for testing. You want to see if everything works correctly befrore assembling everything together. The arm containing the led strip will be finally connected when everything is assembled. So you need to unsolder it again. Alternatively use aligator clips to connect them.

Solder the usb connector and the programming adapter to the arduino. When you are using a arduino nano, you don't need a separate micro usb power adapter and programming adapter since it has usb on board.

This instructable does not explain the programming in detail as you probably know this already and there are other instructables explaining this. See the links in the text.

I have setup a github repository containing the files needed to use with PlatformIO

https://github.com/memolde/TinyWoodLamp/tree/maste...

The files to use with Arduino IDE are here:

https://github.com/memolde/TinyWoodLamp/tree/maste...

You need to install the Neopixel library to get the project compiled

Some basics to the neopixel library can be found here:
https://www.instructables.com/Neopixels-How-Do-The...

https://www.instructables.com/Introduction-to-Neop...

Hints on programming the Arduino pro mini can be found here:

https://www.instructables.com/Using-Arduino-Pro-Mi...

To create a bend lamp arm, we need 2 stripes of thin plywood or other wood (3-4mm thickness). Bending the wood is a little bit tricky, especially for plywood. I have overdone it and the plywood fell apart. The usual way is to steam the wood an bend it when it is steamed. This is basically also what I did:

1. I put the wood into water for about 10 Minutes. When using plywood you should not do it longer, otherwise the plywood may separate.

• Wrap the wood in a wet towel and put it for 60-120 seconds in the microwave depending on the power of your microwave and the wood size. Be careful! The towel is very hot!
• Remove the towel (attention: Hot!) and bend the wood around a pan or pot or whatever round object you have. Secure the wood with clamps. Alternatively there are professional tools for wood bending, but these simple kitchen 'tools' do also work.
• According to the desired shape, leave an end straight as I did. But you are free to use whatever design you want. You may also twist the wood for more sophisticated designs.
• You may want to use a bigger radius first and repeat the bending after a few hours or next day with a smaller radius.
• Let the wood dry completely before you continue with the next step. Otherwise the wood may break when drilling.

To prepare the lamp arm, take one of the wooden arm parts. This will be the inner part, so make sure the concave side looks nice. Mark the middle of the arm on the convex side with a pen.

Put your led strip next to the long marking and mark where the LEDs are. These will be the places you drill holes for each of the LEDs.

Drill the marked holes. You may want to use a small drill to drill from the convex side first and enlarge the hole from the concave side. I used a step drill. The hole needs to be big enough to put one of the LEDs of your LED strip trough it. I used a 10mm hole.

When you have drilled all holes, countersink them. With my step drill this was possible within one step. I have done this from both sides, but it is probably not needed.

Put the other wooden arm on the outer side and mark where the holes are. Remove some of the wood to make space for the LEDs and cabling. Although the LEDs are very slim, you will not be able to glue the wood together without having some space inside. I used a dremel for this, but this could be done with other wood tools like a chisel as well.

Put wood glue on both sides of the two arm parts and fit them together. Make sure the LEDs and cable is positioned correctly since you won't be able to correct this later. To give everything a nice shape clamp the arm to the pot you have used to bend the wood and let the wood glue dry.

Turn on your glue gun und wait until it is really hot. Mine is loosing a lot of glue in this process, but this is ok. Fill some glue in one of the LED holes and wait until it cooled down a bit. Don't be afraid to do something wrong. Once the glue is cold you can remove it with force again without damaging anything, so you could try again.

Do this for all LEDs and you have created the nice glue diffusors. The idea of creating hot glue diffusors where the main inspiration for this project.

Now it is time to put everything together. Solder the connector of the arm to the arduino pin 10 and usb socket VCC and GND.

Then use wood glue to glue the arm to the base. Make sure the usb socket fits into the hole in the arm. You may need to secure the usb socket, so it does not move when you connect the usb cable. I used hot glue for this.

And now you are done. Enjoy your small lamp!

I wanted to add a battery, to make it more transportable, but the design was too small to include a battery with enough capactity. Furthermore the touch sensors need continious power and drain the battery even when the lamp is off.

Some considerations how to save power can be found here:

https://www.instructables.com/Ultra-Low-Power-Trig...

https://www.instructables.com/Reducing-Battery-Pow...

Maybe even an ESP32 can be used since it is able to wake up from deep sleep on touch event:

https://www.instructables.com/ESP32-Deep-Sleep/

https://www.instructables.com/Saving-Battery-Life-...

So, more research is needed and maybe you can see this in action in a future instructable

The size of the lamp may also be of interest. The small base combined with the very light wood makes it look nicely and it fits everywhere, but it makes it also quite unstable. In the video you can see it shaking a little bit. Furthermore there is really not much space to put everything into the base, so you really need to stack things in there. Create your own in the size you want it to have. I wanted to have it tiny.

Bending Wood was somehow easy and complicated at the same time. The possibility to bend the wood in the microwave is really very easy, but you have to consider the watering time. When you do more than 10 Minutes, the plywood may open up at the edges. This requires some experimenting and enough wood to have several tries. I first thought it is a good idea to have the outer grain direction orthogonal to the arm length, but had issues with breaking splinters. So maybe the parallel direction would be better.

By using solid wood the bending is probably easier, but I just had the plywood, so I used it.

The basic idea of the lamp was to use the glue gun to build the diffusors. And this worked out pretty well. They diffuse the light really nicely. You may want to practice before you do it on the bent wood, but I was also able to completly remove the glue once it was cold and start again, so this step is somehow error tolerable.

Have fun building your own lamp.