[Elecraft] toroid enamel wire question

[Don Wilhelm]

Eric,

That insulation scraped off can lead to shorted turns (a bad thing) - t 
happens mostly with the ferrite cores which tend to have sharp edgesm 
the powdered iron cores usually do not have sharp edges.

To prevent the scraping - do not *PULL* the wire through the core - push 
it through.  The technique should be to push the wire through the 
center, then form it around the outside of the core (smoothing it 
against the core body) and then push the wire through for another turn. 
  You will achieve a much tighter wound toroid that way a opposed to 
trying to pull the wire through the center.

For those attending Dayton, stop by the Elecraft booth at 11AM or 2PM 
and you can see the way I do it.

73,
Don W3FPR

Eric Ward wrote:
> A quick question for an experienced (or anyway, confident!) builder: I am winding the first toroid,RFC14, for my K2 and seem be be inadvertently stripping a bit of the red enamel off the wire when I sew it through the toroid.  I don't remember having this happen with the KX1.  It appears that the inside edges of the ferrite toroid are kind of sharp.  I can avoid it by being EXTREMELY careful while winding.  Does it matter if a tiny stretch of insulation is missing?  I.e. should I start over whenever I encounter this?
> TU es 73
> Eric N0HHS
> KX1 #670
> K2 #6106 (in process)
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