RE: Do I have this right? (rotary gap)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Lau, Gary" <gary.lau@xxxxxx>

Rod to motor clearance?  Do you mean from the end of the motor shaft to
the mid-point of the rod?  I assume you're making a plastic arbor out of
HDPE or Delrin?  I suppose 1/8" to 1/4" of solid material would be
sufficient, but I find it difficult to ensure that two nearly
intersecting holes will have a minimum clearance so small.  I'd shoot
for at least 1/2" to give yourself a comfortable margin.  Being wrong
can take out the motor, or worse!

For cutting the rod, I used a small diamond cutting disk in a Dremmel
tool.  You could probably use the normal Dremmel cutting disks, but
it'll be slower and go through a few.

I think most folks set the motor phase experimentally, rather than
trying to predict in advance with a strobe light where the electrodes
should be.  I recommend using John Freau's simple L-C phase shifter, so
you can adjust and set the phase in real time as the coil is operating,
without having to make mechanical adjustments.  See
http://members.aol.com/futuret/page3.html

Regards, Gary


> Original poster: "Adam R." <arabraxas@xxxxxxxxxxx>
>
>
>
> I just got a 3/16" piece of tungsten and am going to cut it down to 7"
(I
> don't know yet how, maybe by a saw and then snapping?), but how much
> clearance can I have from the rod to the motor? 1/8"? or would it be
better
> to go with 1/4"?
>
> Also, concerning syncing the motor with the electrodes. Its an
oriental
> brand motor at 1800 RPM and I have four electrodes. When testing it
under a
> flourescent light, the "black lines" are approx. pointing towards the
screw
> holes on the motor, this is where the electrodes should be, right? Why
is this?
>
> I understand how a sync gap works, but am struggling to applying it
with
> the geometry of the setup I'm planning.
>