Question: Dinghy sailboat flips over when anchored?

(Posted by: on 2010-08-09 13:38:56)

My 13' Snug Harbor Boat Works ThunderCat, (Hull Number 94), is top heavy due to its removable centerboard design. It's hull is somewhere between a Laser and a 420. It is too heavy and unmanageable to pull in and out of the water and/ or remove the mast when I'm not using it, so I keep it anchored in the shallow water in front of my Lake Erie beachhouse. However, when the wind/ waves get big and shifty, the boat capsizes at the end of its anchor rope. This has caused two of the stays to break at different times. If you have any advice on how I could keep my boat upright please suggest.

Posted by: jeff rager on 2010-08-09, 13:45:22

Longer anchor rope??????anybody....anybody.....

Posted by: Girly Brains on 2010-08-09, 14:00:00

Try leaving the board down a little bit - half way even - and trailing a sturdy (floating) bucket or some-such sea anchor astern: get the boat more stable. And make sure any self balers are closed. You could even try a stern anchor as well as the fwd one if you are confident as to the direction of prevailing or violent winds. -|--)

Posted by: D Day on 2010-08-09, 14:34:13

Perhaps add some ballast when not using the boat? Using ballast- anything heavy will work (heavy stones, a couple bags of sand, etc.) will effectively lower the boats center of gravity, making it harder to capsize. It would be like trying to tip over a man. If he has boots made out of heavy steel, he would be far heavier to tip over. Another solution would be to use two anchors, one on each end, or to secure it to a fixed platform of some type, such as a wooden platform or dock of some sort.

Posted by: David Beierl on 2010-08-09, 14:41:17

First of all, make certain that the centerboard is fully retracted. Light top-heavy boats need to be able to skate sideways effortlessly so they don't trip and capsize. Add sponsons, i.e. removable floats attached to the sides of the hull at the point of greatest beam; or if necessary add a pair of outriggers with floats that will bolt to the centerboard trunk and rest (padded) on the gunwale. This will get some buoyancy out where it's needed and make the boat much stiffer by lengthening the lever arm that forces on the mast are working against. I strongly suggest making it a single device that crosses the boat instead of two individual ones -- the forces can be considerable and this arrangement minimizes stress on the fastenings by again giving a long support base -- lifting forces on one side will be supported in compression by the opposite gunwale and in tension by the centerboard trunk attachment. You can leave the outriggers permanently secured to the mooring and simply cast them over the side when you go sailing. For floats I recommend the Styrofoam material made for the purpose. It can be strapped to a flat platform at the end of the outrigger and will last many years without further protection. Do not use "bead-board " or any other material made of expanded beads -- it will become waterlogged. Guess how I know... If you're keeping it in water you can wade out to, none of these measures will be sufficient in a real storm. Lake Erie is a big lake and unless you're in a sheltered spot I'm sure it can build up quite a sea. Moving it into deeper water will be very helpful here.

Posted by: 45 auto on 2010-08-09, 17:46:39

It's a sail boat and will sail under bare pole. Try a bridal on the bow and longer scope with the board down it will rock back and forth and wear the trunk and pin out. tie the rudder if down. Might want to find a better safer location for the boat.