Static Electricity - Mac 25 Sail

[Rocky Styer]

New MacGregor 25 (1985) owner. On the first sail all aboard experienced static electrcity shocks. Had DT8 Suzuki outboard in water at time, but not running. Attempted to lift outboard from water and experience static shocks, used insulated vise grips to loosen wing nut on motor mount and raised with line. Static shocks stopped. temporarily. Static returned later when sailing fast no apparant cause and then stopped for no apparant reason.
Can anyone advise ??

 

[External Combustion]

Re: Static Electricity - Mac 25 Sail

What was the weather like? Wire standing rigging plus a metal mast with no grounding plane can build up static electricity fast in cold dry air. The engine probably was the only ground plane and your bridging to it caused the discharge through you or your passengers.

Nylon sails are worse than Dacron and those with linnen (who has it these days?) have almost no problem. Fiberglass hulls are worse than wooden hulls are worse than metal hulls for this problem.

You might try grounding straps going from the standing rigging to a ground plane of several square feet attached to the bottom of your hull. Add a lightning brush to the top of the mast to allow faster bleed off of the electrons into the air.

How does you radio handle the buildup of electric charge in the hull?