The traditional vertical spiral according to the "cotton outside" scheme, in case both electrical contacts are located below, contains a section of wire that goes down from the top of the spiral down to the contact.
Very often, cotton wool burns in this section coz it is curved and not blown by air passing inside the spiral.
Trying to solve this problem, I wound a double vertical spiral, in which the wire is twisted in a spiral from the bottom up, and then, sharply bending 360 degrees, the wire comes back down in the same spiral:
And it really works, but another problem arises: how to reliably electrically isolate the turns of the spiral from each other?
In a traditional spiral, an electrical shorting between two adjacent turns has little effect on spiral properties. The voltage between the two turns is small, and the neighboring turns, remaining intact, soon heat the damaged pair, it oxidizes and the insulation is restored.
But in the double spiral in case of shorting (and the closer to the contacts, the more destructive this effect), all subsequent turns are turned off altogether, and shorted turns due to spark between them are literally welded to each other.
Question:
How can I pre-create a reliable insulating coating on a steel (SS316) wire?
Very often, cotton wool burns in this section coz it is curved and not blown by air passing inside the spiral.
Trying to solve this problem, I wound a double vertical spiral, in which the wire is twisted in a spiral from the bottom up, and then, sharply bending 360 degrees, the wire comes back down in the same spiral:
And it really works, but another problem arises: how to reliably electrically isolate the turns of the spiral from each other?
In a traditional spiral, an electrical shorting between two adjacent turns has little effect on spiral properties. The voltage between the two turns is small, and the neighboring turns, remaining intact, soon heat the damaged pair, it oxidizes and the insulation is restored.
But in the double spiral in case of shorting (and the closer to the contacts, the more destructive this effect), all subsequent turns are turned off altogether, and shorted turns due to spark between them are literally welded to each other.
Question:
How can I pre-create a reliable insulating coating on a steel (SS316) wire?
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