[Elecraft] Coil winding novice

[Don Wilhelm]

Nick,

I do not understand why folks have a mental block about winding toroids - it
is easy for folks with normal manual dexterity.

A couple hints about winding - count each turn as it passes through the
center of the core - a single wire through the center is 1 turn.  For large
lengths of wire, start in the middle of the wire, wind half the turns, flip
it over and wind the remaining turns.
You 'push' the wire through the center of the toroid when it exits most of
the way, give it a small tug to form the wire on the inside of the core,
then bend the wire around the outside of the core forming it against the
core with a finger as you go around the outside (this is the step that makes
the toroids look neat and tidy).  Once you have formed the wire around the
outside, it is time to start over on the next turn.

Don't worry if you cannot make the first two turns look neat - when you have
the correct number of turns, remove those first two if they look messy and
wind two more on the other end.

What is important is the correct number of turns and the turns spacing -
space the turns to look as close to the manual diagrams as possible.
Toroids will work fine even if their appearance is not the greatest.

The most essential part about toroids is not in the winding, but in
stripping and tinning the wire leads.  Unless otherwise instructed, tin the
leads right up to the core body.  The wire used in the Elecraft kits is heat
strippable, no mechanical stripping is required, and is discouraged because
it often nicks the copper and the lead will eventually break.  The
solder-blob method described in the manual works great, just use a hot
soldering iron (800 degrees is good) and use a tip wide enough to hold a
reasonable blob of solder - use a 1/4 inch chisel tip if you have one, but
1/8 or 3/16 inch chisel tip will work if you add a little patience.  Hold
the wire in the solder blob until the enamel begins to blister and smoke,
then slowly draw the wire through the solder to tin the entire lead.

That is about all there is to it - a couple practice toroids may be needed,
but after that you could be an 'old hand' and wonder what all the anxiety is
about too.  Winding toroids may not be 'fun' for everyone, but it is not
difficult to do a good job.

73,
Don W3FPR

> -----Original Message-----
>
> I am just starting on my K2 and feeling apprehensive about coil
> winding - never  having wound a toroidal coil.My inclination is
> to wind them myself rather than give way and buy a set. It all
> looks straightforward in the instruction manual. Would welcome
> encouragement or cautionary advice.
> 73 Nick G3RWF
>
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