When you apply electricity to a coil, it becomes magnet and gets attracted to a magnet, and when you remove the electricity, it does not get attracted… Theoretically. My idea was to make a velcro like connector, of which close/open state can be controlled by electricity. I made 3 material experiments, stainless steel thread, copper thread and coil wire.
Coil made with Bekinox stainless steel thread. It is embroidered on a fabric with couching stitch. The idea was that as stainless steel thread gets attracted to magnet already, by applying the electricity and making the opposite pole than the permanent magnet, it will repel and result as opening the connection.
The result was rather miserable. It sticks to the magnet no mater which direction the pole is. I tried to switch the +/- direction of electricity to change the electromagnet pole, as well as turning the permanent coil.. and it did not change anything.
Coil made with Karl Grimm Copper thread. It is embroidered on a fabric with couching stitch. The copper thread does not get attracted by the magnet, so the idea is to apply electricity and it sticks to the permanent magnet. When the electricity is shut off, it will not stick.
The result was half promising. It does get attracted to the permanent magnet when electricity is applied, but as the coil is small and the thread is short, it does take quite a lot of current and it gets quite hot. at 0.4A with 2.4V, it started to melt…. to bad!
The last one is with thin coil wire. As the wire is isolated, I have just wrapped around my finger for many times and fixed on a fabric with thread. As it is copper it does not get attracted to magnet. But when the electricity is applied, it does get attracted to the magnet, and compare to the copper thread, it becomes much stronger electromagnet with lower current. (0.2A with 1.1V) and it does not get as hot as the copper thread or the stainless steel thread.
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