"shark fins" on the hull for stabilization?

[pcrg28328]

I have a 69 island maid fiberglass jon boat. It is very narrow. I have seen outrigger type flotation devices for canoes and kayaks. I dont like the way they look or attach so I thought I might be able to attach some "fins" to my boat to keep it from tossing around so much. I have attached a crude drawing of them, please tell me your thoughts.

 

[doberacker]

Re: "shark fins" on the hull for stabilization?

I get how the fins would create drag, but keeping it from tossing "side to side" may not work "without" adding "buoyency" or "floatation" to the boat? I had a Colman Crawdad (Very narrow Jon Boat) and the only way I got it more stable was adding foam to the sides near the transom to help displace the water........ Ugly,,,,,,,, YES,,,,,,,,,,, but it worked? And was inexpensive? Good luck!! D.

 

[oops!]

Re: "shark fins" on the hull for stabilization?

you have a narrow boat.....if you want to stabilize the boat.....sponsons on the sides are required....or an outrigger.

just saw your pic.....it will only help at speed....but they must be installed correctly...or you will have a dangerous list.

if they are just for stabilazation while sitting or fishing.....they wont do diddily

 

[ondarvr]

Re: "shark fins" on the hull for stabilization?

Small fins will do nothing, and large, almost full length fins will slightly reduce the roll from waves while sitting still, but may have a huge negative affect at speed.

 

[pcrg28328]

Re: "shark fins" on the hull for stabilization?

I like the idea of sponsons. I see where somw folks call flotation pods "sponsons" just want to clarify what you mean. Where do they mount, at the water line sitting still or furtrher down, frontward or toward back?

 

[pcrg28328]

Re: "shark fins" on the hull for stabilization?

bump

 

[oops!]

Re: "shark fins" on the hull for stabilization?

sponsons can be nothing more than float sacks on the side of the hull. however they have to be rigidly attached to the side.....two pool noodles floating beside your boat will do nothing.

they are attached at the waterline to increase the beam of your boat....

short story..... there was a yacht refitted in ont canada called absolu 80. the boat (75 feet i think) was top heavy with a narrow beam......when they floated it, the started to list to the point that it might roll over! they had already invested a million or two, so they couldnt walk away.
the fix to the problem was to weld huge sponsons to the side of the boat.....increasing the beam of the ship and adding to its buoyancy.
it worked,,,,,and i beleive the ship is running dinner cruises today

but all in all..for you..it would be cheaper to buy another boat. unless of course you want to add to the beam by cutting the hull in half and glassing in a new keel that would widen the boat