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Re: First big magnifier run
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> From: Tesla List <tesla-at-poodle.pupman-dot-com>
> To: Tesla-list-subscribers-at-poodle.pupman-dot-com
> Subject: Re: First big magnifier run
> Date: Saturday, February 08, 1997 1:25 AM
>
> >>> Subject: First big magnifier run
> >Subject: Re: First big magnifier run
> >>> Subject: First big magnifier run
>
> Subscriber: rhull-at-richmond.infi-dot-net Fri Feb 7 23:00:12 1997
> Date: Fri, 7 Feb 1997 18:56:16 -0500 (EST)
> From: richard hull <rhull-at-richmond.infi-dot-net>
> To: tesla-at-pupman-dot-com
> Subject: Re: First big magnifier run
>
> At 12:25 AM 2/7/97 -0700, you wrote:
> >>> Subject: First big magnifier run
> >
> >Subscriber: nikki-at-fastlane-dot-net Fri Feb 7 00:22:55 1997
> >Date: Thu, 6 Feb 1997 03:18:57 -0600 (CST)
> >From: Bert Pool <nikki-at-fastlane-dot-net>
> >To: tesla-at-pupman-dot-com
> >Subject: Re: First big magnifier run
> >
> >At 10:41 PM 2/5/97 -0700, Ed Wingate wrote:
> >
> >>> Subject: First big magnifier run
> >>
> >[big snip]
> >
> >>
> >>Bill and Bert,
> >>
> >>Congrats and welcome to the magnifier ranks. Isn't it great to have one
> >>work so well on the first try? Especially a magnifier. I am sure that
> >>you will make it to your goal considering your results so far. I'm
truly
> >>glad that the stationary electrode moved away from instead of toward
the
> >>rotor studs with possibly disasterous results. One small example why
> >>safety is paramount.
> >>Keep up the good work.
> >>
> >>Ed Wingate
> >>
> >>
> >
> >Thanks Ed! It's the caps you sold me that are running this thing. I'm
> >gonna stick a big bright yellow bumper sticker on my coil (does it
really
> >have a bumper?) that says "Powered by Wingate." :)
> >
> >I'm thinking about drilling a hole through each of my stationary
electrodes
> >and putting a cotter pin through just in case the set screw vibrates
loose,
> >or if I forget to lock it down again, then the electrode _can't_ move in
too
> >far.
> >
> >Bert Pool
> >nikki-at-fastlane-dot-net
>
>
> Everyone else,
>
> I think Ed and Bert remember this from the Teslathon talk I gave here
last year.
>
> My Series quench rotary is mounted about 10 feet up in the air on the
rear
> wall of the lab. Maggie 11-A was firing one time and one of my tungsten
> disk rim electrodes came adrift and zinged out at bullet velocities. The
> imbalance in the large wheel vibrated the entire rear wall of the lab
(20'
> X17') so bad that the neighbors ran out and thinking a prop plane was
trying
> to avoid crashing as it raced its engines near the ground!!!!
>
> Inside the lab it sounded like the end of the world at the lab
reverberated
> from the huge sounding board. I was quick enough to kill the gap motor
so
> that motor shaft 5/8" was not bent. But it was quite an experience. I
> found the electrode stuck in the concrete floor.
>
> Richard Hull, TCBOR
> >
> >
Richard,
There isn't much we can do about having an electrode fly off of a rotary
gap, but there is a way we can reduce the damage that comes immediately
after.
A fail-safe relay can be constructed so that the spark gap begins rotation
when a switch is first put in its *on* position and then a *start* button
is pushed. This temporarily activates the relay, which then continues to
stay activated because of a pair of now closed relay contacts. A *panic*
switch that is normally closed can be pushed to turn off the relay at any
time. The *panic* switch can be made somewhat automatic if it is made to
open whenever there is severe vibration at the spark gap. This can be
effected by using a snap-type switch, like those made by Microswitch, and
having a piece of metal attached to the metal lever. If the metal is the
right length and has a mass of metal attached at the end, then if there is
a certain amount of vibration it will activate the switch. Such a switch
would need to be calibrated as to what mass of metal to use so that it
doesn't trip under normal operating vibrations. For best results it should
be mounted near the motor. By adjusting the length of the lever and the
mass on the lever it is possible to make the circuit operate at any desired
sensitivity. In fact it can be made so sensitive that it just might turn a
spark gap off before any major damage is done and even before anything
breaks loose. (Though it will only protect in those cases where the problem
shows itself in vibration before breakage occurs. The design is really for
immediate shutdown whenever vibration above a certain point is sensed.)
Another thing that can be done is to wire the relay contacts up so that the
armature goes to the motor, the (N.C.) goes to the *other* side of the
motor, and the (N.O.) goes to the AC (Hot). This arrangement makes it so
that whenever the relay is *off* the motor is not only disconnected from
the AC (Hot), but also has the two motor leads shorted out. This will cause
the motor to come to a stop a bit faster than usual. (It is not as good as
a true electric braking system, but if you already have the relay, you get
this extra feature for free, so why complain?)
If anyone wants a GIF of the above circuit, I would be happy to e-mail it
privately. I take it that attaching GIFs to Tesla list mail is either a
no-no or not implemented. Am I right?
Fr. Tom McGahee