[Elecraft] Toroid Winding Question

[Don Wilhelm]

Clark,

Scraped wire can lead to shorted turns.  The core is not conductive, but 
if adjacent turns short to one another, failure will result.

You are doing it right by pushing the wire through the center rather 
than pulling it.  To keep the turns tight, dress the wire around the 
outside of the core with your finger, then push the wire through the 
center until a small loop remains - you can then snug the turn by 
pulling it the rest of the way through and no scraping should result.

Those ferrite cores do have sharp abrasive corners - it is the nature of 
ferrite cores and one of those things we have to deal with.
The powdered iron cores have smooth corners and do not create the 
scraped enamel problem.

73,
Don W3FPR

Clark Macaulay wrote:
> Perhaps this question has been raised before, but I haven't been able to find it in the archives nor in the manual.  
>    
>   I've built a K1 (words fine) and am now building a K2. Yesterday, while finishing one of the first toroids in kit, I noticed one of the turns had crossed over the previous one, so I began to unwind it. Then I noticed that the wire had the enamel nicked in several places and chose to replace it. 
>    
>   In thiking over what might have happened, wondered if I may have been pulling the winding too tight. Currently, I'm "pushing" the wire through the center of the core rather than "pulling" it so as to keep it away from the core to minimize scratching it. Obviously, though, it's not possible to know if the winding has been scratching in making the bend around inside.
>    
>   So, my question is, to quote Shakespear, is my concern "much ado about nothing"? Am I winding them too tight (I noticed there are LONG leads after winding that could indicate the turns are too tight)?  
>