Lightning bonding

[Gene Regan]

,
Hello all,
   Going through the catalina manual , I read that in 1988 our boats were not bonded for lightning protection. Using the search I have come accross some info on lightning strike stories and some quickie methods of grounding. However I would like to know if any one has installed lightning protection and what methods you may have used. I have an idea in mind but am wondering what some of you have done.

Gene Regan
Drink up me hearties yo ho

[Stu Jackson]

Gene

Was one of your "hits" on:

http://c34.org/mainsheet/pdf/1995_no1.pdf   ?

The tech notes have a few lightning writeups.

Stu

[Ted Pounds]

Gene,

I did the quick-and-dirty protection on "Molly Rose" and ran a #00 wire from the base of the mast to the nearest keel bolt (about a 1 foot run).  I got a special bi-metal connector that solves the corrosion issue for the copper wire and the alumnium mast.  I  think I got the connector from West Marine, but I couldn't find it in their latest catalog.  To do the job completely you need to tie the shrouds (and maybe the fore- and back-stays) to the same grounding point.  The idea is to give the current a place to cleanly exit so it doesn't punch a hole in the hull to reach ground. Most of the current will go down the mast, but some (depending on the power of the stike) will go down the stays.

Ted

[Gene Regan]

Yes Stu ,  
   An interesting story to say the least but I wonder if the protection they had was properly installed, as it seems as though they experienced some flashovers to other systems on the boat. Then maybe thats an inherent trait to bonding the boat, therefore catalina's decision to do nothing at all. The more I read on it the more it makes me wonder.
But without knowning if Herb used correct sized wire or not one cant be sure. Or how far away from mast the dynaplate was . I was told that # 8 agw wire from mast & chainplates to copper 1/2 inch pipe directly to dynaplate connection affords the best route for the lightning to follow.Seems that the pipe offers low resistance due to its being hollow thus sending strike to the plate more effectivly. Hmmmm.I wonder.
I'm taking the mast down in the spring and this was one of the things I'd planned on doing as we get alot of lightning in my area and other boats around me have been hit more than once. Maybe I'm in a bad zone ??? We'll see.  

Thanks

Gene Regan

Drink up, me'earties, yo ho

[Ted Pounds]

Gene,

Bonded or not, if the boat is hit by lightning electonics will fry.  The only way to prevent it is to disconect everyting and and move the connections far enough away that the charge won't jump the air gap.  Some of the strike will go down the wiring in the mast and from there has enough power to take out anything wired to DC  :eek:.  All the bonding will prevent is damage to the hull.  The jury is still out on those ion disipators (static wicks we call them on airplanes).  A friend of mine had one and he got fried - though he also had the tallest mast by far on his dock.

Ted

[Andrew Harvey]

Gene
I installed a 3/8" copper plate to a keel bolt. There was enough thread exposed to sandwich the plate with another nut over top.
I ran #4 wire from the mast and the pulpits so far. First mate insists that I complete the job to include stays and shrouds. I haven't figured out how to get to the chainplates and maintains esthetics at the same time.
Cheers

[Stu Jackson]

The chainplates come down underneath the deck and are connected to the hull behind the seat backs with one inch stainless rods.  There are double bolts at the bottom of them.  Seems to be no reason not to be able to connect them them there and then easily run the wiring down to the keel.

[Ron Hill]

The other school of thought to Lightening protection thru grounding is to use a Positive Ion Dissipater and help eliminate the attraction.

Once the Two million volt/lb gorilla (lightening) comes onboard, the wire size doesn't seem to be too important.