|Topic Review (Newest First)|
|01-29-2001 08:50 PM|
SO IT SEEMS,.....that after all is said and done; as to be expected, there is no single answer; and thus, I revert to the basis for my maritime trades and the integral foundation for ALL installations I do, and sailors at large do well to make this their NUMBER ONE motto......cover all the bases, leave nothing to chance,overbuild 10/20%, the SEA has no mercy and last but not least....Lifes a Reach, then You jybe...
|01-29-2001 10:59 AM|
GEE FOLKS...THANKS FOR ALL THE RESPONSE AND IDEAS. I WROTE SAILNET, ASK THE EXPERT, AND HERE IS WHAT DAN TOLD ME. BTW, ISN''T SAILNET A REALLY COOL SITE????sorry about the little >>, but i thought it would be a good source of information.
We''d be happy to have you post that message, although it''s not as complete
an answer as we''d like to give you, it does guide the reader to other
informative sources. Just don''t portray it as an end-all answer, because
that''s certainly not my intention. All the best,
----- Original Message -----
From: "R.j." <email@example.com>
Sent: Monday, January 29, 2001 12:13 PM
Subject: Re: Ask Experts
> THANK YOU!!!! FOR YOUR QUICK RESPONSE.!!!!! MAY I POST
> THIS ON MY MESSAGE BOARD. I THINK OTHERS MAY LIKE TO
> SEE IT????
> --- firstname.lastname@example.org wrote:
> > Dear Sailnet User:
> > On 2001-01-27 00:47:45, you asked:
> > Lightning is sure a confusing topic. I posted a
> > question in the message board, but still getting
> > unclear answers. I was wondering...if there is
> > someway to direct the current incase i get hit. My
> > thoughts were attaching a copper cable at the base
> > of the mast and running it over the side into the
> > water. I have read the pros and cons of attaching a
> > lightning protection system and what i need is more
> > or less emergency measures incase i get caught in a
> > thunder storm>?????
> > Here is our answer:
> > You''re right, there are a number of differing
> > opinions on this topic. Friends of mine who just
> > spent a year cruising to the Caribbean and back
> > swear by the use of their lightning wire--a device
> > they clamp to the shrouds and then throw the
> > remainder of the wire overboard to ground the boat.
> > That said, many of the experts prefer a
> > well-grounded lightning rod fixed to the masthead.
> > Nigel Calder writes comprehensively about such
> > systems in his book "Boatowner''s Mechanical and
> > Electrical Manual," which is available in the
> > SailNet Store on line
> > (http://www.sailnet.com/store/item.cfm?pid=230).
> > Also, you might want to do a search on SailNet for
> > lightning as we have four or five pretty good
> > articles with recommendations.
> > Here''s wishing you the best of luck on this topic.
> > Dan Dickison
> > Editorial Director
> > SailNet.com
> > Where Sailors Get It
> > www.sailnet.com
> > further questions, please visit
> > www.sailent.com/collections/ask_expert/index.cfm
> > and don''t miss our store specials!
> > http://www.sailnet.com/store/specials.cfm
|01-29-2001 09:16 AM|
I was under the impression that a ion dissapator had to be grounded to a ground shoe can you explain or do you just attach it to top of mast?
|01-29-2001 08:52 AM|
I would suggest that you simply buy an ion dissipation device for about $50 and attach it to the top of your mast. Such a device does not increase your chance of getting hit, it decreases the chance. You can goto forespar''s site for a more technical explanation. Good luck.
|01-27-2001 06:19 AM|
The boat, Newport 30, sailing for 15 years coming from Bermuda to Beaufort NC. Weather front on horizon at night illuminated by lightning from all the way port to starboard...shut done all electronics and disconnected them, all wiring from mast disconnected...batteries on off...try to make no electical field. coming closer now night time like daytime..see for miles...closer now too bright...look away as boat cabin top vanishes in the bright lite at such an intensity....in it...pressure pulses from all sides...with eyes closed tight brightness almost too much....inner eye lids ablaze...at height of strikes to water around us (1 strike every 3-10 seconds) a strike hit so close the rain on our faces(foul weather gear on with gloves, only leaving face exposed) had to be wiped away because it got too hot! It was incredible and this whole thing lasted, from seeing it afar to it passing about 15-20 minutes....by the way, we had no grounding at all on the boat and I figure that with lightning....if you have no grounding it is like lightning trying to find you in the fog, with grounding I feel you may attract it
|01-27-2001 12:51 AM|
Yes Rich,...that''s the general conclusion of my 32 years of boatbuilding study/work....the stays are much better conductors and run a straighter course.The copper grounding would be of a fair dimension, and left unpainted under the waterline and connect directly to stay. The best would be as it was done with full on external chainplates bolted right onto the outside of the hull. In emergencies a guy can shackle a length of chain to the turnbuckle and dangle a few deet of length inti the water and leave it.A vessel underway could do the same. It is a good idea to not bond anything from the upper cabin to the engine/shaft grounding.A bolt of lightning can blow shoot your prop like a torpedo if it takes an arc from the mast to the motor to the shaft.One thing for sure, you Can take a shot and live or you can blow the bottom right out of your boat......
|01-26-2001 08:42 PM|
Thank you RichH. Your message was very informative. It sounds like there are no easy answers when it comes to lighning. Still don''t know what I should do and it sounds like if someone would know, you would. So I guess I will get fried no matter what I do...HEY there are worse ways to go!!!!!!
|01-26-2001 08:28 PM|
I dont think that anyone has the answer for you !!! However, making a sharp angle from the mast to the gunnel and then overboard probably wont work as lightening seems to prefer to take a straight path. It would probably be more prudent to attach the wire from your backstay and drag it in the water -- but I dont think anyone has an absolute answer because as you state this may enhance a strike. The last ''hit'' I took came down the mast/antenna wire jumped through wire in the bilge and blew into the encapsulated keel with a ''starburst'' out the side (small leakage). Perhaps a better place to ask this question would be in a general aviation (airplane) message board, and ask those who fly ''plastic'' airplanes as they seem to get ''hit'' more often than boaters. I myself have posed the queston to marine insurance underwriters.... and always get NO answer (for obvious reasons).
As a long time sailor (with 3 hits) I''d like to know what others think or have experienced with lightening protection. My ''hits'' were all when anchored or moored.
I think my preference at this time would be to bond the shrouds to external chainplates hence directly bonded underwater to a keel shoe (on an encapsulated keel) --- but I''m only guessing.
|01-26-2001 08:42 AM|
It seems like whether to install a lightning protection system is a hit or miss situation. On one hand, install one and you are more likely to be hit, although with less damage, and on the other hand a lot of sailboats don''t have any kind of protection. I personally have a 24 ft fiberglass boat with an aluminum mast. I am land locked and never over a few hours from my home dock. I would be considered a weekend crusier. My Question: Can a system be improvised such as wraping a copper wire around the base of the mast and running the wire overboard into the water with an iron weight provide a makeshift ground and provide more protection from lightening, or should I just leave it alone and hope for the best, or do I really need an expensive lightening protection system?