I am designing my first TC and need to build a coil winder. My first secondary coil will be: Diameter: 4" Length: 18 inches Wire: 26 AWG Since the coil is not too long, I am thinking about a plywood framesupporting a motor, turns counter, and arbor. A foot switch would be used aswell as some type of speed control.
I used a section of threaded rod (3/8" IIRC) that passed through the coilform (made plywood endcaps inside each end of the PVC pipe), and passed it through ball-bearing units on each end (supported by 2x4s). This allowed the coilform to freely rotate.
On one end, I attached a short section of automotive fuel line to the threaded rod, the other end of the fuel line went to the shaft on my motor (a modified kitchen blender). The fuel line was a good coupler in this application, as it allowed for the motor to be slightly off-axis (not intentional, just didn't want to fuss with perfect alignment), and also functioned as a crude but effective clutch.
Below and in front of this was a horizontal ground rod that I used to hold the spool for the wire.
As for speed control, since the blender motor was a universal motor (AC/DC), I drove it with a variac for speed control. I used a footswitch (momentary) to turn the motor on.
I also used a counter on mine, created by gluing a small magnet on one of the plywood endcaps, with a stationary reed switch triggering an electromechanical counting device.
The whole shebang was assembled using drywall screws and 2x4s and attached to my workbench, which permitted me to dissasemble it and store it with a very small footprint (ensuring future use).
Mind you, my first winder was a vertical winder, with the coil set on top of a record player. Later incarnations of that design used a manually turned bicycle wheel, but the horizontal motorized winder is a lot easier to use (especially with longer coils).
Best of luck to 'ya, Jon _______________________________________________ Tesla mailing list Tesla@xxxxxxxxxxxxxx http://www.pupman.com/mailman/listinfo/tesla