From: Bob Blick <bobblick@outlook.com>
To: Microcontroller discussion list - Public. <piclist@mit.edu>
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Date: Wed, 15 Jul 2020 11:28:19 -0700
Subject: Re: [EE] Microwave Oven Transformers
Thread-Topic: [EE] Microwave Oven Transformers
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Hi Graham,

The choke is only going to be used at low voltage so you're right, I don't =
need to worry too much about insulation.

I could strip off the insulation and bundle the four strands together befor=
e insulating. It would be rather stiff, but I've got tough fingers. Would u=
se a lot of polyimide tape, I expect it to be about 30 turns. The widest I =
have is 30mm I think.

Varnishing it is an interesting thought. I've got no experience with varnis=
h or shellac, so finding something that would work from my local hardware s=
tore will be an interesting experiment.

I have some 8AWH battery cable too. But probably not enough.

Thanks for the ideas!

Bob
________________________________________
From: piclist-bounces@mit.edu <piclist-bounces@mit.edu> on behalf of graham=
 foulkes=20
Sent: Wednesday, July 15, 2020 10:57 AM
To: Microcontroller discussion list - Public.
Subject: Re: [EE] Microwave Oven Transformers

HI
120 amp windings at low voltage, you don't need thick insulation on the
wire. Maybe strip off the house cable insulation and lap wind with thin
tape, electronic polyamide high temperature tape preferrably. I have used
thin cotton tape to insulate scondary coils in a home built welder, still
running 30 years later.
Shellac lacquer is also an alternative, does not soften much with
temperature increase and has good dielectric properties. Avoid PVC
electrical tape, softens too easily and punctures when winding, stretches
and so thins out.

On Wed, Jul 15, 2020, 7:38 AM Bob Blick  wrote:

> That's pretty nice! I guess I shouldn't give up on finding a source for
> enameled wire. I will start with my current plan and see how much
> inductance I get, since I have lots of house wire.
> Thanks, Bob
>
--=20
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