Re: Faraday cage

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Tesla729-at-cs-dot-com>

In a message dated 5/10/02 12:54:04 AM Pacific Daylight Time, 
tesla-at-pupman-dot-com writes:

Hi Terry,

<< I was thinking of a simple 1x2 wood frame with aluminum screening.  Simple,
 fast, and easily handled.  Not real big and easy to take down. >>

So how good are your carpentry skills? I assume you have access to
common carpentry tools. As far as I can see, this should work fine.

<<1.  Is there any chance of setting the aluminum (bug screen as on windows
<      and doors) on fire?  I know some metals like steel wool can light up 
and I
<<    just wanted to check on aluminum screening. >>

I've never seen aluminum screen ignite, but I that doesn't under any circum-
stances mean that it never would :-) "I" use the  "poultry screen wire" for my
Faraday shield in my shop. It's not a Faraday "cage" in that it does not com-
pletely surround anything, it is just a "shield" between yours truly and the 
8 to
10 ft power arcs that spew from my pole pig  coil :-) 13 ft. is about the 
maxi-
mum distance that I can seperate myself from my coil in my small shop and
with occasional 10 ft. + sparks even in a claustrophobic 12 X 24 shop build-
ing, that's obviously WAY TOO CLOSE for comfort without a grounded shield.
The poultry screen wire (chicken wire) is available at most home improve-
ment warehouses (Home Depot, Lowes, ect). 

<< 2.  Arcing directly to the screen will tend to transmit RFI and magnetic
<  fields go right through it, but do you think it would be worthwhile? >>>

I think it would. Since installing my Faraday "shield", I never experinece 
the 
typical RF burn/shocks from touching grounded metal objects since the 
shield is obviously between me and the spark spewing monster, even 
when I'm cranking 7 to 8 kVA :-) Now if I'm dumb enough to step on the
business side of the shield, then that' a different story ;-)

<< 3.  Any construction tips? >>

I think you've got the right idea. Just make sure that your 1X2 wood frame
is sturdy enough that it want bent or break since a 6 ft. cube would be
pretty big for 1X2s. Bracing your 90 degree corners with 6" "L" brackets
would probably sturdy it up pretty good for you.

<< Cheers,

 <<    Terry  >>>>>

Spark safely,
David Rieben