The Quest... The quest for parts...





I had just about given up on restoring my Geo. Stevens pickup coil winder... not because of lack of
'want-to' but because it was proving almost impossible to find any kind of usable parts.

That is, until this envelope showed up here last weekend.

What is it?

This is a package of parts I ordered from China some time ago - one of the most important parts
for the whole winder. Without them, the Stevens was just a big computerized paperweight!

Read on...


An explanation is in order, so pardon my drawing skills.

I explained awhile back how the Geo. Stevens coil winder works... as the main motor rotates the coil
the traverse rod moves back and forth across the coil bearing the wire guide, which guides the wire
to be wound onto the coil.

The Stevens was originally set up by the original owner to wind bobbinless pinball machine solenoid coils,
like the one at the drawing shown on the left. This setup uses a winder blade mounted to the wire guide
(shown in another photo), which slides over the top of the coil like a sled as the wire guide moves back
and forth. The coil wire ran through a hole in the winder blade.

I am converting the Stevens to wind guitar pickup coil bobbins, which very quickly became a major problem.

The winder blade originally found on the Stevens' wire guide is 1/4 inch wide, and a humbucker or
P90 pickup's coil bobbin also has a space between the bobbin top and bottom of 1/4 inch. Therefore,
the coil winder would never move across the bobbin as it should to properly fill the bobbin,
 but instead it laid down the coil wire in a very narrow line right down the center of the bobbin!

After much research, I found out that winding bobbined coils like guitar pickups (see the drawing
at the right) were done with a 'winder nozzle' that fit down in between the coil's bobbin sides and still
moved back and forth to fill up the bobbin.

I had enough problems trying to find the cams and gears to make the Stevens work...
 now *where* was I going to find a winder nozzle for a 70 year old machine???




Here is the original 1940's Geo. Stevens winder guide assembly, showing the winder blade for winding
bobbinless solenoid coils. The coil wire runs through the 'C shaped' hole and slot at the top of the blade,
and the blade slides back and forth along the top of the coil.





I decided that all those brand new coil winders I saw on the Web had to get their parts from somewhere...
and eventually I found out where.

This is a catalog page for a wire guide nozzle for a modern CNC coil winder. The nozzle is hollow
and uses a donut shaped real ruby bearing as a guide that the coil wire rides through
to not damage the insulation on ultrafine coil wire.

The basic idea is the same as the 'jewels' in high grade analog wristwatches - the ruby watch bearings
keep the watch's parts from wearing out. In my application, the ruby wire guide bearing keeps the
insulation from wearing off of the coil wire or otherwise getting damaged.

This is very important, because there can be up to *1/4 mile* of 42 gauge coil wire
wound in just one 5S7 pickup coil! For real.





Here is a photo of one of the actual wire guide nozzles I bought. The ruby bearing is the 'glassy area'
shown at the extreme small end of the nozzle.

The wire running through this nozzle is a piece of 42 gauge heavy Formvar coil wire!
42 AWG coil wire has a diameter of roughly .0026 (2.6 thousandths of an inch)




This is an empty 5S7 pickup bobbin I'm using to show how this nozzle fits between the plates of a
pickup bobbin. As this pickup bobbin rotates, the nozzle would move back and forth between the bobbin
plates and the coil wire runs through the center of the nozzle to the bobbin.

This is one of the most important parts of the Stevens coil winder, because the nozzle is the actual
guide that places the coil wire on the pickup bobbin, instead of my fingers. All the other winder parts do is
position this nozzle in the correct position relative to the bobbin. The nozzle must also be as accurately
made and long wearing as possible so the coil wire's insulation doesn't become damaged in winding
and short out the coil.


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