Hull/Rigging Grounding Plates...

[Christian Van H]

Hi all! Here's a conundrum: my boat came with something I had never seen before... Galvanized (I think) plates about 1 1/4" wide X 1/8" thick bolted to the hull between each upper chainplate and extending down into the water, I assume to act as ground straps. Do they work??? I have no idea. Are they ugly? YOU BET! I have several options here; remove them for good and just fill the 1/4" mounting holes, make new ones from 316SS or Bronze, or reuse the incredibly ugly old ones. Anyone out there ever heard of anything like these? Might not have been done for the last thirty years... Thanks, Chris

[Christian Van H]

I should have mentioned that these grounding straps are on the OUTSIDE of the hull, while the chainplates are on the inside. They connect to the chainplates using the lowest chainplate mounting bolt...

[Blue Stocking]

Chris, these don't sound like grounding straps. Are you sure that they wern't added to further distribute the shear load from the chainplates fasteners?

[hellosailor]

Are the galvanized straps simply clapped onto the outside of the hull, not glassed into it? With no mechanical fastening except that one shared bolt?

If so, I'd also suspect it was some sort of kludge job, maybe meant as a lightning ground path (since lightning will be coming straight down the rigging) that could be ignored or removed as you saw fit.

[Christian Van H]

Originally Posted by Blue Stocking

Chris, these don't sound like grounding straps. Are you sure that they wern't added to further distribute the shear load from the chainplates fasteners?

Good call, but I don't think so, judging from their construction. Both lower bolts that hold them to the hull are only 1/4". Only the top bolt is 1/2", as it's an actual chainplate bolt. I thought they were smart at first, but I doubt they are much in the way of protection. Kind of like the old advice to hang a chain attached to the shrouds over the side in a T-Storm...