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Re: Rotary Modifications Update
---------- Forwarded message ----------
Date: Wed, 15 Oct 1997 18:33:44 -0500
From: Chuck Curran <ccurran-at-execpc-dot-com>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: Rotary Modifications Update
John:
Thanks for your reply. I am running at 385 PPS on a 12 inch diameter circle
for the six moving electrodes. This is 3850 RPM, from one of the Carter
0-10,000 RPM motors. I run it up with a autotransformer that actually feeds
a 10 amp control transformer that gives 60 VAC output. I use a full wave
bridge and a couple of big filter caps to end up with 84 volts DC no load.
I originally ran the 60 VAC and got 2250 RPM with 12 moving electrodes and
then I switched to the DC voltage to get the higher RPM to provide a shorter
dwell time. All of this fuss with the transformer is really simply a safety
measure--I don't really need to see that 14" diameter disk of G10 at 10,000
RPM by accident. I put the transformer in to simply limit the maximum RPM
in a very positive manner. It was free, too.
Is your "offset" method basically shifting the stationary electrodes so the
result is to minimize the time for alignment and/or conduction?
Chuck
-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Sunday, October 12, 1997 11:14 PM
Subject: Re: Rotary Modifications Update
>
>
>---------- Forwarded message ----------
>Date: Sun, 12 Oct 1997 18:06:14 -0400 (EDT)
>From: FutureT-at-aol-dot-com
>To: tesla-at-pupman-dot-com
>Subject: Re: Rotary Modifications Update
>
>In a message dated 97-10-12 14:12:07 EDT, you write:
>
><< snip
>> I had been running with brass stationary electrodes that were effectively
>> about 3/8" across at the tapered end that conducted. In order to search
>> for better system performance by addressing the quench issue, I installed
>> 1/8" diameter tungsten rods, heat sunk by the original 1" diameter brass
>> rod that is 1 1/4" long. System performance improved and initially
things
>> looked good, >>snip
>
>Chuck,
>
>Well, the question is, why did the performance improve? Was the
>quench-time actually decreased, or was refiring of the gap prevented,
>does tungsten quench better than brass, etc. I remember on one
>coil, I used 1/4" electrodes and I got thumping in the pole tranny and
>the system drew 16 amps. When I went to an "offset" method that
>effectively reduced my dwell time to zero, the thumping went away,
>and the current dropped down to 13 amps, but spark length remained
>the same. Break-rate was about 600 presentations per second. Yet
>many coilers used even wider gaps (1/2") with good results, but
>perhaps at lower break-rates. What break-rate and rpm do you use
>and what is the effective rotor diameter?
>
>John Freau
>
>