Re: first results - magnifier setup

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Finn Hammer by way of Terry Fritz <teslalist-at-qwest-dot-net>" <f-h-at-c.dk>



Tesla list skriver:
 >
 > Original poster: "Christoph Bohr by way of Terry Fritz 
<teslalist-at-qwest-dot-net>" <cb-at-luebke-lands.de>

snip


 > After grinding two 3/4" flats into the rotor it won't run smooth anymore,
 > the speed is contantly varying from ca 2800 to 3000 rpm in 1 second cycles.


 > Christoph

Christoph.

This is called hunting, the motor is trying to get into sync, but cannot
quite get there yet.

This happens when there is not yet enough material removed from the
rotor, so you might want to grind off a litle bit more. Go slowly, from
now, since remowing too much will produce a motor that pulls too much
current at full volts input, or pulls too weekly at a voltage where it
will run cool.

You may also already have taken off too much material. Have you got a
variac, can you tell me at what voltage the hunting starts, when you
ramp up the voltage sloly.

Cheers, Finn Hammer