Should I earth the rigging, whilst on the hard???

Cariadco

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The boat's out of the water, propped up on the queyside, now should I drop a cable from the shrouds, and connect it to a rod, driven into the ground?

We've had a few lightning strikes in Gouvia Marina (Corfu) this past year, and a lot of damage ensued, so would earthing the boat protect it by this 'lightning conductor' or would it make my mast even more attractive to lightning??

Perhaps it's better as it is, in it's insulated-from-earth state?

Thanks,
 
if you want to do that, then it would be best to have a completely separate heavy duty cable (e.g. lorry battery cable or other low-resistance conductor) running from above the top of the mast to the ground (earth) rod.

If you just connect a cable to the mast, the rigging, chainplates and everything else are likely to be damaged - but obviously not as much as if you don't earth the boat.


If you think anchor threads are fun, then try discussing pointed versus dissipating lightning rods with the two proponent sides :)
 
If you're concerned about strike damage, have your mast taken down; even fitting a large conductor won't stop the alloy being fried at the masthead. Is there a record of masts being struck in that yard?
 
Also how high is your mast compared to others there?? I am not an expert but I believe that it would take the easiest path so likely the tallest mast there????
 
Also how high is your mast compared to others there?? I am not an expert but I believe that it would take the easiest path so likely the tallest mast there????

There doesn't seem to be any sense in it sometimes and I suspect it takes the path of least resistance.

We had a very violent thunder storm earlier in the year, with strikes into the sea within about 50 metres of us and, onto a nearby low island. Strangely, none of the boats (including a steel one) were struck, although masts were higher than the island.

Another time on a Biscay crossing we must have had a buzz from a thunder cloud because all the instruments went haywire for half an hour or so before behaving properly again yet radar showed the squall to be over 4 miles away.
 
Thanks.

Thanks for your comments.

Same sort of results, as I've had from my friends out here.

Everybody has a different view...! No conclusion!! So I'll leave it as it is, ie not connected to ground.
Regards.
 
Lightning protection

Do not earth the rigging via the SS stay wires. These have relatively high resistance and can be damaged in loss of heat treatment (temper) by relatively low currents. If you want, then earth the Ali mast itself with a heavy wire to earth. Be careful of the connection mast to wire as this is likely to get very hot at high currents and burn the Ali. I don't agree that the mast will be burned significantly at the top where lightning hits. (other gear may be damaged) Aircraft frequently get lightning strikes. Usually lightning enters at nose or wing tip and exits at tail or other wing. Ali being a good conductor is hardly more than scorched at the entry point. It is medium resistance materials that really get damaged like trees and stainless steel.
All this is theoretical. What you do is up to you. I certainly don't worry about lightning. good luck olewill
 
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