Winding Toroidal Cores

[Joe]

Need some info about how to wind toroidal inductors of various sizes. If anyone has experience doing this and can share some tricks I would really appreciate it!

[Ripthorn]

Depends on your core.  If you are going air core, you can just use anything the right shape to wind around.  If you have a ferrite core or something like that, you start at one place, keep windings neat and tight, and go round and round until you have it wound to your specs.  Is this for a transformer or an inductor?

[R.G.]

You can do this two ways.
1. Calculate ahead of time how much copper wire length you need for the winding and then needle-and-thread it.
2. Calculate ahead of time how much copper wire length you need for the winding and then wind this on a circular shuttle which goes through the toroid center. Unwind the wire onto the toroid core and then remove the shuttle.

The penalty for guessing too little copper wire length is that you get to unwind it all and start over.

[Processaurus]

It must be a funny machine that winds them at a factory.

[Cliff Schecht]

The things you'll want to aim for is even spacing in the windings if possible and, if you're building a coupled inductor, you want the two (or more) windings to be coupled together as close as possible. Try to wrap the windings tightly around the core so that you immobilize them, otherwise you can start picking up microphonics through the inductor. If you're getting into higher frequencies it helps to take smaller gauges of wire and twisting them together tightly, this helps to counteract skin effect.

What is the toroid for? We could maybe give you some more specific advice if we know the application.

[frank_p]

It must be a funny machine that winds them at a factory.

There are a lot of videos on youtube:
http://www.youtube.com/watch?v=rtfKedQ7dsk&feature=related
http://www.youtube.com/watch?v=Yt_Nz7SnSEg&NR=1

[amptramp]

It must be a funny machine that winds them at a factory.

There are videos on this site showing coils being wound:

http://www.gormanmachine.com/

And yes, it is a funny machine.