[N] Re: Lowering mast during storm/ Carbon fiber masthead charge diffusion fingers

james nolan (nolan_laboratories@email.msn.com)
Wed, 1 Sep 1999 15:06:29 -0600

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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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Tom:
Thanks for posting the nice pictures of Lake Granby and thanks especially
for not posting the one of me falling off of the windsurfer and straddling
the mast.
A cheapo lightning disappator (spelling) can be made by taking a short
length (6") of heavy gauge stranded copper wire, such as a car battery cable
or jumper cable. The heavier the gauge and the finer the strands the
better. Strip off 3-4" of insulator on one end and peel out the individual
strands to make a "lollipop tree" of the strands. On the other end crimp a
large lug (car battery ground type). Make sure the insulation is removed on
this end for conductivity to the lug. Bolt this lug to the top of the mast,
in which you'll probably have to drill a hole. You may want to put up more
than one. Total cost less than $10. Note: This will not absolutely prevent
lightning from striking you, it will only reduce your chances. When
lightning comes around, I head for shore. You also must provide a grounding
path for the mast, I use a long chain off of the forestay into the water.

Jim Nolan (now a believer in outsailing the current)

-----Original Message-----
From: Thos. Westerman <thomasw@vanion.com>
To: Bill Wallace <billw@rdmcorp.com>
Cc: wwpotter@tscnet.com <wwpotter@tscnet.com>
Date: Tuesday, August 31, 1999 12:53 PM
Subject: Lowering mast during storm/ Carbon fiber masthead charge diffusion
fingers

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> West Wight Potter Website at URL
> http://www.lesbois.com/wwpotter/
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>Bill Wallace wrote:
>>You might want to re-consider lowering a mast in the event of a storm. It
>>probably increases your overall danger, since you are actually handling
the
>>mast for a time during the storm (a larger danger by itself), and you now
>>have a conductor running the length of the boat and beyond. This will
>>pickup stray electricity in the water much better than a vertical mast,
and
>>will thus be a good conductor. Also, the horizontal mast now has no
>>obvious path for the electricity to take, so it will fan out, rather than
>>trying to go out the bottom of the mast. Finally, as you found out, doing
>>anything unnecessary during a storm increases your danger of an accident.
>>Bill
>
>Thanks for the Advice Bill. I contacted Garmin about the GPS--got off
>lucky, for $89 and my cost to ship to them, they will repair the unit to
>original factory specs, even if they have to replace the whole thing (which
>includes shipping back to me too). Lucky.
>
>I sincerely doubt I could have paid for a new companion way hatch, or even
>repair work to a damaged one for $89 had the GPS not distributed the 1 inch
>contact point of the mast trailing end into a 4 inch footprint of the GPS
>bottom. That is one way to look at it. The GPS saved my Hatch.
>
>I plan to buy more galvanized chain for my anchor and will either get more
>for my side shroud lines too, or make sure to carry jumper cables for the
>same use and then leave the mast up.
>
>Also does anyone know how I could make some of those little "fingers" of
>rope like fibers for the mast head--like the ones you see on airplane wings
>for diffusing the charge--without having to buy an expensive sailboat
>lightning kit? How would I go about mounting/attaching/grounding the fiber
>bundle,etc? Nolan?
>