Sewable soft circuits are a unique way to explore electronics and fashion. Using conductive stainless steel thread, you can sew circuits that power lights in unique ways. When you add a metal snap, you can create a switch to turn the circuit on and off, which conserves battery power and can also create unique interactive effects. This tutorial is inspired by Leah Buechley’s e-textile activities located in Sew Electric.
GATHER MATERIALS: (Vendors – Sparkfun, Adafruit, Amazon)
- LED lights with resistors
- battery (3 volt CR2032 coin size)
- conductive thread (stainless steel thread)
- sewing needle (self-threading needles work best)
- felt fabric
- sewable metal snaps (male and female ends that fit together)
- assorted sewing notions (fabric pencils, buttons, scrap fabric, sequins, regular sewing thread, etc.)
PART ONE – PLAN THE CIRCUIT:
- Draw on paper to plan your design. Indicate placement for the battery and LED light and where the conductive thread will connect the components.
- Remember you will use one piece of conductive thread to connect “+” sides and a separate piece to connect “-” sides. Think about the metal snaps as being “+” and “-” components as well because when they touch they will complete the circuit path in order to power the LED light.
- Do not cross the positive and negative lines of conductive thread.
- Consider how you can use regular thread to complete non-conductive aspects of your design.
- Lay out your materials.
- Test batteries and LED light to ensure they work.
THINK ABOUT: How can the design use as little conductive thread as possible and still maintain a balance of conductivity and aesthetics?
PART TWO – MAKE THE FABRIC BATTERY POUCH: (*Note: You can purchase battery holders but they are usually too expensive to use for large group activities.)
- Cut two squares of fabric (slightly larger than battery).
- Sew a small circle of conductive thread in center of each square (about ¼ or ½ size of battery).
- Use regular thread to stitch three sides of squares into a pouch (leaving one side open for access).
- Test to make sure battery fits. Make sure battery is accessible for replacement. Used batteries cannot be thrown in regular trash and must be disposed of properly.
THINK ABOUT: How much conductive thread is needed to ensure maximum power from the battery pouch? Will the battery pouch be placed on the inside (non-viewable) side of the cuff or appear on the outside (viewable) side of the cuff?
PART THREE – SEW THE CIRCUIT:
- Mark the longer “+” lead of the LED light(s) with Sharpie marker.
- Coil resistor ends of LED light(s) into sewable circles.
- Sew components onto fabric. Remember to use separate pieces of conductive thread for “+” and “-” connections. Don’t forget that the metal snaps will act as your on/off switch and one will need to be sewn on the outside visible side of cuff and the other sewn on the inside hidden side of the cuff.
- Secure ends with hot glue.
THINK ABOUT: How can you insulate the conductive thread without compromising the aesthetics of the design? Is the cuff comfortable and functional for everyday wear?
- How many LEDs can you power with one battery? What other types of circuit designs can you use to power more than one component?
- What other conductive materials can you use to make the sewable circuit interactive or modular?