Date: Tue, 8 Feb 2005 11:40:14 -0700
Reply-To: jimt <camper@TACTICAL-BUS.INFO>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: jimt <camper@TACTICAL-BUS.INFO>
Subject: Re: Cleaning bad grounds
In-Reply-To: <42089067.11218.4E60DE@localhost>
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On 2/8/05 11:11 AM, "Jack" <john.cook58@VERIZON.NET> wrote:
> I've stayed out of this but a couple of comments need some response.
>
> 1. Star washers. Do NOT use between terminal and ground surface
> unless absolutely necessary to cut through paint or something. If
> they heat up it's because a higher resistance has been introduced
> into the electrical contact system via the washer. Bad!
>
> 2. Threads. Grease, anti-seize, peanut butter ... doesn't matter!
> Any good contact system relies on the flat surfaces, NOT on the
> threads. If using some substance on the threads creates a higher
> resistance then something is wrong.
>
> 3. A typical stackup. Per "best practices" in industry.
> Body metal. Bright & clean bare metal.
> Ideally, surface is plated or tinned.
> Terminal (ring or spade). Bright & clean. Proper connection
> to wire assumed (different set of problems).
> Flat metal washer. Sometimes omitted.
> Lock washer.
> Purpose is to maintain high contact pressure.
> Nut or bolt/screw head.
>
> 4. If in bad environment, cover stack with grease or suitable
> compound - I prefer silicon (e.g., DC4). Helps prevent corrosion and
> eventual corruption of the gas tight metal/metal contact.
>
> There are, of course, variations on the above. Key point. Well
> designed ground systems do NOT normally rely on threads for
> electrical contact unless there's no choice.
>
> //Jack
> '85 GL
>
>
When assigned in tactical outfits with a lot of exposed to the environment
grounding the same rules applied
Grounding surfaces polished clean and depending on metal tinned.
Only a flat washer between contact and ground surface permitted and it had
to be larger diameter than the contact being used, and be of the correct
metal type. Lock washer on top of contact with preferably another smaller
flat washer first (metal type again if used). Then an antisieze compound or
grease lightly applied to top area threads and nut applied. Then depending
on type of exterior connection sometimes grease over everything afterwards.
There were also rules on what the ground was made of (braid, solid,
multiconductor, etc)
Interior grounding was not much different except no grease allowed.
Grounds inspected on every scheduled inspection for corrosion.
••••••••••••••••••••••••••••••••••••••••
jimt
Planned insanity is best.
Remember that sanity is optional.
http://www.tactical-bus.info (tech info)
http://www.westydriver.com
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