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Old 02-05-2012, 15:57   #16
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Re: Simple Lightning Protection Idea?

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i can honestly say--aint no such a thing as lightning protection.
Pretty much. Avoiding Florida is about the best advice I can offer. They have more lightning than any place. Given a near miss with lightning is enough to kill you, you don't need more than you can avoid.
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Old 02-05-2012, 16:33   #17
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Re: Simple Lightning Protection Idea?

I'm going by the theory that since I was hit by lightning at the age of 12 on a soccer field and lightning never strikes twice, I'm in good shape. Well at least now you understand why I am the way I am...
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Old 03-05-2012, 01:46   #18
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Re: Simple Lightning Protection Idea?

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Originally Posted by Celestialsailor View Post
I'm going by the theory that since I was hit by lightning at the age of 12 on a soccer field and lightning never strikes twice, I'm in good shape. Well at least now you understand why I am the way I am...
Serious? If you don't mind sharing, what sort of injuries?? Were you the tallest , how did the soccer field fare?
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Old 03-05-2012, 06:20   #19
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In lieu of chains use battery jumper cables with the clamp cut off one end and insulation stripped back a foot and wire partly in twisted. Won't mark the topsides. Is a much better conductor than chain and had more surface area in the water. I have carried them for 30+ years. Not hit by lightening so far!
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Old 03-05-2012, 06:37   #20
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Re: Simple Lightning Protection Idea?

btw--lightning DOES strike twice--the nasa engineer in louisiana did--bendytoy 55, second time almost half way to his house from the boat inclusive of everything --he WAS allegedly protected from the bolt..dont presume anything about lightning--it WILL go where it WANTS to go.
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Old 03-05-2012, 06:48   #21
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Re: Simple Lightning Protection Idea?

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Serious? If you don't mind sharing, what sort of injuries?? Were you the tallest , how did the soccer field fare?
We assumed it hit the goal post. It electrified the ground and all the kids on the field had their hair stand up. I was the 60's and the teachers could have cared less.
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Old 03-05-2012, 15:33   #22
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Re: Simple Lightning Protection Idea?

Was standing on a fishing pier once and lightning came extremely close. I don't know if it actually struck someting, didn't notice anything burst into flames... but it was close enough that me and several others suddenly looked like Albert Einstein on a bad hair day. Made a few people drop to the ground, and everyone else took off running....Also could feel the energy all the way through, like getting hit with a stun gun. Had to check to make sure my heart was still beating after that one

The guy that was struck and killed I mentioned previously, happened directly in front of a Christian Retreat hotel on the beach. A few days after it happened I talked to the manager there who said it happened to someone else in almost the exact same spot a year earlier. And that was about the 4th time It happened in the 10 years he worked there...

On another note; I read an insurance claim study (can't seem to find it again) that was meant to figure out if certain boats, certain places, etc.. were more likely than others to get struck. It was done over the course of several years in Northwest FL. Gave all kinds of data about lightning strikes and the damage done.
The only pattern they were able to find was; in a marina setting, catamarans were most likely to be struck. At first it was assumed because they had taller masts, but after the study, they determined it was the distance between masts that made the biggest difference.... the more singled out masts were more likely to be struck... Many Cats got struck sitting next to monohulls with taller masts. So basically, if you have the tallest mast in the marina, get a slip next to a catamaran
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Old 04-05-2012, 14:42   #23
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Re: Simple Lightning Protection Idea?

Lighting protection. Now more relevant than ever:
Lightning Strikes Man's Scrotum
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Old 04-05-2012, 15:02   #24
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Re: Simple Lightning Protection Idea?

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Originally Posted by callmecrazy View Post
... I read an insurance claim study (can't seem to find it again) that was meant to figure out if certain boats, certain places, etc.. were more likely than others to get struck. It was done over the course of several years in Northwest FL. Gave all kinds of data about lightning strikes and the damage done...
The following statistics are based on all of the BoatUS Marine Insurance claims for lightning damage over a five-year period.
Goto ➥ BoatUS.com - Seaworthy Magazine

See also ➥ Catamarans
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Old 04-05-2012, 15:40   #25
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Re: Simple Lightning Protection Idea?

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Originally Posted by SailBobC View Post
In lieu of chains use battery jumper cables with the clamp cut off one end and insulation stripped back a foot and wire partly in twisted. Won't mark the topsides. Is a much better conductor than chain and had more surface area in the water. I have carried them for 30+ years. Not hit by lightening so far!

Seconded.

Chain conducts, but the junctions between links dont contact with much surface area, causing an increase in resistance at these junctions. and the bulk of the lightning's charge may divert to another path to ground that has a lower resistance, like your mast.

Never tried it, but i would think that a continuous heavy gage (2AWG) line bolted to the top of your mast, running alongside a shroud and into the water (with a foot or so of stripped wire in the water), with minimal angles of incidence on the way down, would be the best you could do. maybe shrink sleeve over the wire to increase the insulation resistance. this "solution" would be a 1-shot charlie since the cable insulation will most likely become a puddle on your deck after a strike.
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Old 06-05-2012, 09:02   #26
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Re: Simple Lightning Protection Idea?

The boat next to me did that(actually used battery cables), they got hit and it blew out their electronics. In addition they had the one of those diffuser things on top of their mast because they had already been hit once before. Who said lightning doesn't strike twice?!
They had a tall mast (64'), mine is only 46', so the best protection, be in slip next to a boat with a higher mast.
Tom
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Old 06-05-2012, 16:24   #27
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Re: Simple Lightning Protection Idea?

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Originally Posted by teejayevans View Post
The boat next to me did that(actually used battery cables), they got hit and it blew out their electronics. In addition they had the one of those diffuser things on top of their mast because they had already been hit once before. Who said lightning doesn't strike twice?!
They had a tall mast (64'), mine is only 46', so the best protection, be in slip next to a boat with a higher mast.
Tom
that method will divert the strike and prevent it from blowing out your thru-hulls and sinking your boat. his electronics were probably fried from the EMP from the strike, which with the sensitivity of modern electronic devices, wouldnt take much to cook them. proximity is enough. to prevent this kind of damage, you'd have to stow your devices unplugged in a farraday cage before the strike.
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Old 06-05-2012, 17:15   #28
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Re: Simple Lightning Protection Idea?

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Originally Posted by heyniceguy View Post
that method will divert the strike and prevent it from blowing out your thru-hulls and sinking your boat.
I believe the "blowing out of the thru-hulls" is a myth, I know several boats that have been hit, none ever had any problems with thru-hulls.
Bronze conducts electricity as well as most steels and melting point of 1750 degrees, if the rigging can handle it, the seacocks should be able to.
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Old 06-05-2012, 18:12   #29
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Re: Simple Lightning Protection Idea?

I read a very extensive article once , cant remember where basically its unpredictable and no mater what size ground cables ect. it would not be large enough BUT changing your electrical potential during the storm is a BIG nono!!!!!many cases were reported when anchor chains touched bottom, people stepped ashore,reached out touched docks ect! so have your chain over the side early or BAM!!! I have had close calls with 3 strikes near me ,once after stepping of a friends boat had walked a shot distance BAM it was hit .The waterline looked as if it had been shot with a shotgun no gelcoat only frayed fiberglass 10inches wide all the way around the boat
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Old 06-05-2012, 19:47   #30
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Re: Simple Lightning Protection Idea?

I believe a strike is initiated by a streamer coming up from the earth, this is supported by research done at the U of Fl. I isolate my boats from ground to prevent the relatively low potential streamer from originating at my location. Once a strike begins it can and will go everywhere there is the remotest path to ground. Ionized air is a good conductor. You can not contain the energy of a lightning strike in a wire conductor. In over 25 yrs in Fl I have never been directly or indirectly hit. My boat has been within less than 100 ft of telephone poles, which are shorter than my mast, that have been struck on several occasions over that time, close enough for the RF to fry autopilots, VHF's and GPS receivers.It seems there are no guarantees with lightning but these are my thoughts. Dave
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