How to make the centerboard spring up on impact

[trimarannaga]

I have a Searunner trimaran. I am looking for information on what others with swing up centerboards do to allow the centerboard to release and swing up if impacted.
Right now, a winch is needed to lower it, and i put the line on a cleat. If i were to impact a coralhead or run aground, i am afraid that not only the centerboard but the case also would be damaged.
Any suggestions?

[Fore and Aft]

We use one of these quick release cleats to hold down the rudder blade on our 32 foot yacht. It works well and instantly releases when we touch bottom.
Cheers
https://binksmarine.com.au/store/yac...-anodised-c257

[Tusitala]

on our searunner we have a simple figure 8 knot in the centerboard line with a piece of small diameter cordage looped through the knot. once we winch the board down to the desired position we cleat the small cord off, not the centerboard line. when we hit something the string breaks and the board pops up. easy to use and maintain!

Pat

[admiralslater]

A friend used an very undersized shackle to hold the turning block in place that would break on impact. Happen once in twenty or so years

[Cadence]

Originally Posted by trimarannaga

I have a Searunner trimaran. I am looking for information on what others with swing up centerboards do to allow the centerboard to release and swing up if impacted.
Right now, a winch is needed to lower it, and i put the line on a cleat. If i were to impact a coralhead or run aground, i am afraid that not only the centerboard but the case also would be damaged.
Any suggestions?

Place a length of fishing line between the line for the CB and the cleat. You may have to play with line test. Cheap and dirty but works.

[senormechanico]

Originally Posted by Fore and Aft

We use one of these quick release cleats to hold down the rudder blade on our 32 foot yacht. It works well and instantly releases when we touch bottom.
Cheers
https://binksmarine.com.au/store/yac...-anodised-c257

Our Dragonfly 1000 has a couple of those. One for the centerboard, the other for the rudder.

[earthbm]

Originally Posted by senormechanico

Our Dragonfly 1000 has a couple of those. One for the centerboard, the other for the rudder.

FWIW, when I hit a whale or a seal (? There was nothing else nearby, and no sound) that cleat didn’t work. Had to get a new board.

[Fore and Aft]

earthbm, sounds like you had the load screw in too tight. When we put ours on the rudder I dived on the rudder and gave it a kick to see if it realeased. It took a bit of adjustment but eventually we had the right balance for imapct/release. You can have it set so a light push instantly realeases it.

Cheers

[earthbm]

That might be. The spring and ball mechanism did get a bit stiff (salt air?), so the screw was hard to calibrate.

I like the sacrificial cordage solution better.

Another one was described to me by Mike Leneman once for the rudder — drill a hole in the rudder and use a sacrificial plastic pin.

At the time my rudder downhaul was slipping creating excessive lee helm. Replacing the downhaul line with a thicker low stretch polyester rope solved it.