Introduction: Sunset Glow Bowl

Intro: Felting is a really easy process the kids and adults can enjoy with and gratifying results. Add light with the Circuit Playground Express (CPE) for some great effects! This project is good for beginners and is broken down into three stages: Making the felted bowl, coding the CPE, and assembling the two.

The photo above is taken from a website "" which sells wool roving. (no connection to the author of this project). Wool roving can be purchased online, at some art supply stores and at shops that sell yarn and other textile arts materials.

Assignment: Make a felted bowl that glows like a sunset.

Time: This project took me 5 hours.

Learning Objective: Pair circuitry with traditional media.


  • Paper and Color Pencils for Sketching
  • Smooth ball to use as a form for making felted bowl (3" to 5" in diameter, such as a tennis ball sized ball or small children's play ball)
  • 5 - 8 oz. Wool roving in different colors. How much you need will depend on the size of the ball you use.
  • Felting needles (standard size)
  • Foam backing material
  • Dish Soap
  • Access to warm water
  • Old nylons (not cut up yet)
  • Plastic and Towels to protect work surface
  • Sink or big bowl to work over
  • Scissors
  • Hair dryer (optional)
  • Circuit Playground Express , USB cable, Battery Holder with wires and 3 AAA batteries
  • Needle and Thread
  • Laptop or computer and access to Make Code Programming Environment.

Skills: Hand-sewing, Programming in Make Code, Wet and Dry Felting

Step 1: Make the Felt Bowl


Wet felting is a traditional process that results from the natural characteristics of wool fibers to bind together when water and friction are applied. The wool has small barbs that allows for this. The basic process will be to layer thin layers of wool on top of each other and then applying a felting process to create a strong felt in the shape of a bowl. Experiment with layering different colors of wool for beautiful effects.

Helpful Hint: Have students do a quick pre-assignment project making a small 4" x 4" square of felt using a wet felting technique in order to learn how to pull and layer wool, as well as what colors can be created from layering the wool.

  1. Sketch your bowl showing 2 or 3 sides first so that you know what you want it to look like before starting with the wool. Sketching will save you time and materials by helping you to plan how you want to layer colors.
  2. Organize your workspace. Place materials in front of you: your sketch, ball, feel, nylons, soap, a bowl to work over (unless you are working over a sink), scissors
  3. To layer the wool, tear very thin pieces of wool (too thick and your layers won't stick together when felted), layer the wool on the ball covering about 2/3 of the ball. When placing layers of felt on top of each other, change direction, even slightly, so that you have something of a criss cross pattern. This will make a stronger network of fibers. Flatten the layers of wool with you hands as you work. I found it helpful to set the ball on a bowl while I worked.
  4. To finish layering, you want about 10 thin layers on the ball. 2/3 of the ball should be covered with layers of wool.
  5. To prepare for felting, pull the nylon over the ball being careful not to shift the wool out of place. The nylon should form a smooth sheath around the ball. Pull it taught and tie the nylon so that it full contains the ball.
  6. Start felting: For this step you will want to work where water will not get all over, either over a sink or bowl with towels or plastic underneath. Try not to make a mess! Wet the ball until the felt is soaked through. Squeeze a quarter size dollop of dish soap onto the ball and begin working it across the whole surface of the ball. The goal here is to soak all the felt with warm soapy water. To make the wool felt the fibers must be rubbed together. To do this rub all surfaces of the nylon encased ball using flat hands, making sure not to push too hard at first while the wool is still loosely layered. As the wool flattens and felts the fibers will hold together more and you can begin to rub harder. Continue rubbing for about 10 minutes. If you don't rub long enough the wool will not felt enough and not be sturdy. You can check from time to time to see how much the wool has felted so far and if you are missing any areas. Add more soap and water as you go, or soak up extra bubbles with a towel, as needed. The felt will feel like a spongy wet matte. It should hold together when you gently pull at it.
  7. Remove the nylon when you are done felting the wool. With the nylon still on the ball, first rinse the ball under cold water to remove the soapy water. Then squeeze with a towel to remove as much water as possible. Carefully remove the nylon. You will have a felt-covered ball now. If the felt is too thin you can add more layers of wool and repeat all steps to felt it. If the felt seems thick and strong enough it's time to remove it from the ball. The felt will be somewhat stretchy and can be gently nudged off the ball. Go slowly and work carefully. You do not want to pull to hard because you could mishap the felt which can be worked somewhat into a shape but is not elastic, and will not contract back into a round shape easily.
  8. Once off the ball the felt should still have a round shape. It can be sculpted by hand somewhat. When it is a shape that you like, leave it to dry overnight. You can use a hairdryer to speed up the process. Be careful when handling the felted bowl so you do not pull it out of shape.

Step 2: Code Your Circuit Playground Express

  1. Create a code that sets the colors of the LED's on the CPE, and programs the lights to slowly fade in and out from bright to dim. Choose sunset-like colors. Follow the code in the screenshot above.
  2. Download the code to your CPE
  3. Plug the CPE into your computer using a USB cable and download the code to your CPE.

Step 3: Sew Electronic Components Into Bowl

Sew the CPE and the Battery Back to the bowl.

  1. First you will attach the CPE to the bowl. Unplug the CPE from your computer. Using thread and needle, attach the board to the inside of the bowl, buttons facing up. Cover the board with a thin to medium layer of wool, enough to hide the board but so that the lights can still be seen glowing through the felt. Use dry felting techniques to felt the new wool to the felted wool. (see link HERE for instructions on technique)
  2. Attach the battery pack to the bottom of the bowl facing out using thread and needle. If your battery pack does not have anywhere to attach it by sewing you can sew a small felt pocket to the bottom of the bowl instead, and this can be used to hold your battery pack.
  3. Run the wires through the bottom of the felted bowl from your battery pack to the CPE.
  4. Insert batteries into the holder and watch your bowl glow!

Step 4: Take It Further!

Try different variations of this project

  • Try writing a code that will change the colors as they fade in and out.
  • Change the timing of the fade
  • Create a pair of bowls, one representing sunrise and, one, sunset.

Step 5: Resources

Wool Roving can be purchased at a store or online. Look for Roving that