Message-Id: <3.0.3.32.20000227230123.031688f0@olsusa.com>
Date: Sun, 27 Feb 2000 23:01:23 -0500
To: lancair.list@olsusa.com
From: Robert E Froelich <refroelich@juno.com> (by way of Marvin Kaye <marvkaye@olsusa.com>)
Subject: Re:Carbon fiber conduction
Mime-Version: 1.0

          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
          <<  Lancair Builders' Mail List  >>
          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> 
>>
The resistance from end to end of a 6 foot by one inch piece of trimmed
carbon fiber was near 1 ohm.  I did not want static charges going from
the wing to the flaps and ailerons through the connecting bearings and
damaging them.  Solution was to tie the cabon from each together with
copper braid and then tie the braid to the gear box. Thus, all of the
carbon pieces if the aircraft are electrically tied together and then on
to the engine, engine mount and nose gear.  A strap was added between the
fuselage, horizontal stab and elevators inside the tail. 

The resistance from the nose gear to the wings is in the neighborhood of
10 ohms.  In terms of a static charges high voltage, this resistance is a
non-factor.

I found hysol joints to be a good conductors (low resistance). 

I wrote about this years ago and the resistance figures given then were
current and  precise, but the exact values do not alter the concept.

Bob

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
LML website:   http://www.olsusa.com/Users/Mkaye/maillist.html
Builders' Bookstore:   http://www.buildersbooks.com/lancair

Please send your photos and drawings to marvkaye@olsusa.com.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>