Re: spark gaps

To: tesla-at-pupman-dot-com
Subject: Re: spark gaps
From: "Robert W. Stephens" <rwstephens-at-ptbo.igs-dot-net>
Date: Thu, 24 Oct 1996 16:51:08 -0500
>>From bert.hickman-at-aquila-dot-comWed Oct 23 22:14:09 1996
>Date: Wed, 23 Oct 1996 09:29:09 -0700
>From: Bert Hickman <bert.hickman-at-aquila-dot-com>
>To: tesla-at-pupman-dot-com
>Subject: Re: spark gaps

>Tesla List wrote:
>> 
>> >From rwstephens-at-ptbo.igs-dot-netTue Oct 22 21:44:46 1996
>> Date: Tue, 22 Oct 1996 22:04:58 -0500
>> From: "Robert W. Stephens" <rwstephens-at-ptbo.igs-dot-net>
><SNIP>
>> 
>> All,
>> 
>> I've been meaning to share my thoughts on the use of a vacuum cleaner
>> blower to negatively pressurize a fixed gap spark gap container and
>> draw outside air through the gaps and then after electro-treating the
>> nitrogen in the air into nitric acid and the oxygen onto ozone, this
>> nasty stuff gets sucked through the windings of the blower motor,
>> since vacuum cleaner blower motors are designed that the air sucked by them
>> passes over and through the motor windings for cooling.  Has anyone ever
>> heard of the concept that ozone attacks electric motor insulation and shortens
>> motor life?  Somehow this design concept appears flawed to me.
>> 
>> rwstephens
>
>Robert,
>
>American Science and Surplus has a high speed 120 V vacuum
>motor/assembly ($12.00) that sucks clean air through the motor! I just
>replaced my previously zapped motor, and discovered that the little fan
>on the motor shaft at the top draws clean air through the motor and into
>the vacuum chamber. This probably reduces the total vacuum you can draw,
>but otherwise it seems to run OK! Maybe it was a manufacturing screw-up,
>and this is why they're surplus!
>
>-- Bert --


Bert,

These very compact, high powered motors designed for vacuum cleaner 
or similar service _must_  move high speed air through themselves to 
cool the motor or they will quickly overheat and burn out. This 
feature is not a manufacturing screw-up but rather a deliberate 
design feature.  Take one of your surplus motors and block the air inlet or outlet,
whichever is convenient, and let it run until it self destructs.  If you time 
the experiment I'll wager it will be a much shorter lifetime than is 
desireable for a typical electrical product.

I may have misunderstood your comment about 'manufacturing screw-up'.
If you are merely saying that the air intake and oulet seem to be 
reversed from what is normal for such motors, then the point I am 
making, although still relevant, is not applicable to your comment.  
In that case, as Roseanne Roseanna Danna used to say,.... "Never Mind!".  

regards,
rwstephens

<Some wiseman once said it couldn't be done, but hey, these motors suck and
 blow at the same time!>  : )