[TCML] holding the ends of windings in place.

["Christoph Bohr" <cb@xxxxxxxxxxxxxxx>]

Hello folks.

Because someone asked me about this, I will try to
clarify what I meant when speaking of another method of
fastening the ends of winding.
This better applies to transformes and chokes, less for
secondaries.
Pics would be much better, but I don't have any and won't
be able to take some in the near future.
Moreover, my english is not too good, but I will try my best,
so, long story short, heres what you asked for:

Start of winding:
take a piece of adequate cloth 1/2inch wide and 1.5inches long.
fold it around the wire so both ends point to one side, leave a
sufficient length of wire for your connections to be made later.

Additionally you might want to use some small hose or heat shrink
tubing at the point where the wire goes through the V shaped cloth.

Hold the wire and cloth against your core  / bobbin at the outer
end with the long ends of the cloth pointing in the direction you are
going to wind ( inwards ). Make the first turn so that the wire comes
to rest upon the cloth. Make sure the wire is under good tension and
finds its way close and parallel to the beginning  of the first turn. 
Continue winding and you will see, that the cloth will be firmly held in 
place under it. 


End of layer:
About 15 or 20 turn from the end, start to wind over another piece of cloth.
Same size but this time just flat on the core so it extends about half its length
over the edge of the core. Then fold it over the winding and start to wind the
next layer, which in turn will hold the strip in place. 
You can to this in several places around the diameter for extra stability.


End of Winding:
some distance from the end of the winding insert another
v-shaped strip of cloth under the wire and wrap it to the core while
winding. Wind until there is just a small lug of the cloth left. Big enought
so that you can still get the wire through it but small enought to give 
a good hold. Run the wire through it and bend it to the opposite direction.


This is what I do and probably far from professional, but with a little 
practice it can give very tidy and stable windings without the use of
a bobbin. Craft paper helps with stability.
One example of a coil I wound using this method is this one:
http://www.luebke-lands.de/pics/winding3.jpg
These are 10K+ turns without bobbin and everything remains 
in place nicely...
You can use some extra "wraps" at the beginning and end for it
might hold the wire better in place, I don't but YMMV....


hope this fields more questions that it rieses ;-)

best regards

Christoph Bohr
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