N Cook:
1/5 nts is way too high......
For most rf coils, torroids, transformers, etc..... 5% of NTS is adequate...
especially for soft drawn enamel insulated copper.
If you are doing motor armature windings or other rotating coils that will
be subject to centrifugal forces, the 10% number works fine for most of
these applications.
What exactly are you doing?
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Best Regards,
Daniel Sofie
Electronics Supply & Repair
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"N Cook" wrote in message
...
Cannot find any on the web.
Easy enough to determine
the ulimate tensile strength of a given length of copper wire
but is the ideal back tensiom while winding say 1/5
of that UTS or some other factor/s ?