Message-ID: <3602DBC6.ABC5CE40@accex.net>
Date: Fri, 18 Sep 1998 15:16:38 -0700
From: Dan Brown <danb@accex.net>
Organization: Citizen's Association for More Ordnance
To: Dan Schaefer <dfschaefer@usa.net>, lancair.list@olsusa.com
Subject: Re: conductor, anodizing, gas strut
References: <19980918185150.20539.qmail@www07.netaddress.usa.net>
Mime-Version: 1.0

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Dan Schaefer wrote:

> The reason you don't want to use a steel firewall pass-thru conductor
> hasn't got a thing to do with steel's tendency to magnetize but rather
> because it's a lousy conductor. When you're trying to get enough

	It's not _that_ lousy of a conductor, and any losses are made up for
easily enough by just going for a bigger bolt.  Of course, that weighs
more...

	A 1-gauge wire has a diameter of .289", and is good for a little over
100 amps continuously.  A 1/2" copper bolt ought to be good for about
300 amps continuous duty (having about 3x the cross-sectional area of a
1-gauge wire).  How much current needs to flow here?  I'd think the
alternator output plus a comfortable cushion.

> Oh yeah, if you can get it done without it being ridiculously
> expensive, have your threaded copper gizmos silver-plated. In my other

	Very bad idea, I think.  Silver has a very low resistance (though just
the plating won't help much at DC or low AC frequencies), but the oxide
has very high resistance.  That's why electronic parts are often
gold-plated; gold doesn't corrode.  In this application, though, it
seems like any plating would be overkill.

--
Dan Brown, KE6MKS, danb@accex.net
Meddle not in the affairs of dragons, for you are crunchy and taste good
with ketchup.