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polyurethane for magnet wire insulation

polyurethane for magnet wire insulation

polyurethane for magnet wire insulation

i need to wind a transformer with very thick magnet wires (for a spot welder). the thick copper wires, i already have, but i still need to insulate it. i don't want to spent a lot of cash with polyimide or polyester coatings, nor do i have the equipment and expertise to apply them properly. so i'm going with polyurethane varnish as coating. but varnishes are not specialized for being flexible, electrically insulating and heat resistant. is there anything i can add to it to make it so?? maybe dissolving polystyrene into it?? how about sulfur?? anything, any cheap way to go.

P.S. i am not up to anything dangerous. i just need to make a cheap spot welder.

RE: polyurethane for magnet wire insulation

I'd buy a spot welder.

This is not the right field (high current and considerable DC voltages ARE "arc's and sparks!!!!" and you WILL be all to probable to be "welding" right inside the ad-hock transformer you are building.

RE: polyurethane for magnet wire insulation

You should have bought magnet wire that is already insulated. All the magnet wires we use come with appropriate insulation on the wire. Getting uniform consistent wire insulation is not a do it yourself task.

Look for wire with NEMA MW 1000 HEAVY coatings. These will come in many different temperature ratings and classes, it's up to you to select the right one.


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