🚀 go-pugleaf

It seems then central point that the system shoiuld have a supply reel
driven by a torque motor , one set of pinch rollers with a brake to
control the tension in the wire before the coating area, a second
set of pinch rollers driven by a variable speed motor to drive with
wire and a take up reel, driven by a torque motor has never been
clearly stated.

I would use two reels, perhaps specially made, so that the full length
of wire can be wound on a reel with a negligible change in the winding
diameter.  Let's say keeping the change in winding diameter between 5
and 10% of the core diameter.  If you have sufficient distance between
the driven set of pinch rollers and the take-up reel the wire might
level wind by itself.  It would be worth the time to make a quick test
to see if thre wire will level wind itself without assistance.

The torque motors could be the small Bodine Electric AC  Induction
motors.  Their torque is easily controlled by a small Variac.  C & H
Surplus in Pasadena California sells these motors and small Variac
Autoformers at surplus prices.  For the brake on the supply side pinch
roller set a magnetic powder clutch would be ideal. Of course the
brake will control the tension of the wire in the coating area.  C & H
may have some of these in the catalog, I do not have it at hand as I
write this.  They also have DC motors with tachometer outputs that
could be used for the driving pinch rollers.  Also there are a number
of suppliers of small, precisely speed controlled DC motor drives.  I
think you would want to have a system with either a "digital tach" or
a dc voltage tachometer, I would shy away from those DC controllers
that sense the motor speed by calculating it from the applied voltage
and the current drawn by the motor for this application.

For the pinch rollers I would use one steel roller and a hard rubber
pinch roller working together.  I would connect both the brake and the
drive motot to the steel roller side,  The reel motors will not need
any control beyond setting their supply voltage to obtain the optinum
winding and unwinding tension in the wire, since the reels will wind
at a substantially constant radius.

Del Stanton  sd20@earthlink.net