RE: Terry Blake gap Maximum power?

["Tesla list" <tesla@xxxxxxxxxx>]

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

I assume you're referring to Terry's "propeller gap" configuration?  My
experience with such a gap goes only as far as using with a 15/60 NST,
though I know that Terry has used it with at least a PT.

I don't think that the motor size directly limits the power that such a
gap can be used with.  It's more the diameter of the tungsten rod
"propeller" and the ability to accommodate temperature rise in the rods
that determines the maximum power.  I've only seen propeller gaps use
5/32" or smaller rods, but I suspect that a much thicker rod could also
work.  You'd have to try it, maybe reducing the length slightly to
reduce the rotational mass if it's right on the edge.  And rather than
using a plastic arbor to hold the rod, use phenolic or G10 to tolerate a
greater temperature rise.  My synchronous propeller gap may be seen at
http://www.laushaus.com/tesla/sync_gap.htm.

As far as the motor being able to spin up and synch-lock with a heavy
rod - I'm not sure that there's any real advantage to using a
synchronous gap for high powered systems.  Most pig-powered systems seem
to do better at high break rates with asynchronous RSG's.

One more thing - I'm not even sure that system "power" is the limiting
thing as much as gap current.  Using a high inductance primary to lower
the gap current will probably result in cooler operation and higher
efficiency.

Regards, Gary Lau
MA, USA

> Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
>
> Hi All,
>
> I finally found a Classic Teletype 3600 R/PM teletype motor.
> Nostalgic for me because, to date myself, because I used to work on
> Teletypes when I was young. How much power do you run through these
gaps?
>
> Thanks,
> Jim Mora
>