Conductive thread is ideal for introducing electronics into textiles projects. The thread looks and behaves like conventional sewing thread with the added bonus of being conductive, allowing the thread to be used in the place of wires, with conventional electronics.
Electrical characteristics
The thread has a low resistance but it is not a perfect conductor. The thread has a resistance of approximately 0.4 ohm / cm (40 ohm / m). This is quite sufficient for, say, powering LEDs over quite large distances. If very long lengths of thread are used to connect the LEDs, this may result in the LEDs being slightly dimmer. Resistance does not vary significantly from one length of thread to the next.Physical characteristics
The thread has a breaking strain of around 9.3 pounds (4.2 kilos). It comprises roughly 96 individual filaments, each coated with a micron-thick layer of natural silver. In construction, 16 of these filaments are wound together to form an initial twist; two of these twists are then twisted together, and finally three of these twists are combined to form the finished thread. The thread is around 18 denier in thickness (a denier is a measurement of a threads weight or thickness). This means it is slightly heavier than a regular sewing thread, but not as heavy as an upholstery thread. It can be hand sewn, or it can be sewn on most sewing machines using either a regular needle or the next size up. The thread does not fray.Example applications of conductive thread
There are many applications in which conductive thread and fabrics can be used.Electronics in textiles
Conductive thread is perfect for adding electronics into textiles (clothing, hats, bags etc.). This does not have to be just LEDs. The thread could be used to connect many different types of sensors or input devices, and also many types of output devices.ESD (Electro static discharge) prevention
Many electronics can be damaged by what is known as electro static discharge. This is likely to happen when the electronic components are handled. This is most likely to occur during the manufacturing process (when the parts are put onto the PCB). To prevent this manufacturers often require their employees to wear conductive clothing. These garments allow any static build up to be conducted away in a safe manner, therefore protecting the sensitive electronic parts.Fencing
Conductive materials have been used in fencing for a number of years. During a fencing match the competitors wear a conductive jacket that covers the ‘scoring’ area. An opponent scores points by striking the scoring area with their foil (sword). The contact between the metal foil and the conductive jacket can be detected by an electronic circuit and is used to register valid ‘strikes’. The jackets used are very expensive and it is common for owners to repair worn jackets with patches of conductive material and thread. Download a pdf version of this page here 
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