Exteding a hull?

Extending a hull?

Does anyone have any info on or has done a hull extention ?
I have a 21ft fly bridge . glass over ply. want to extend it 4ft.
Thanks Matt

 

Matt, You need to give us more information on the boat. Type of power, planing or displacement, type of use intended and speed, pictures etc. You are talking about a radical change, must proceed carefully. One thing in your favor is theat glass over ply will be easy to work with! Don

 

Hi Don. It will have a 225 outboard on a pod bolted to the transom, will do aprox 30 knts, its a fly bridge cruiser mainly for fishing with a v beath up front.and its a planing hull. . Ive searched the net but cant find any info or pic anywhere. Thanks Mate.

 

I've done something similar 2 years ago. Made the extension in a makeshift mold, laminated aluminium L-profile all around the inside edge and bolted the box to the existing transom after applying a layer of marine sealant (Sikaflex). In my case I needed another ft of engine room for 2 Berkeley jets, so I made holes in the old transom where I needed them, left the rest intact.
I contemplated laminating directly to the existing hull, but decided not to because I didn't trust the adherence to 25 yrs old laminate, especially the bilge that has been oily for as long as I can remember. Experts told me that it can be done, but the contact area should be 4-5 times the wall thickness.

 

Hi CDK, thanks for the reply. so u build an alloy extention tub and bolted it to the exsisting transom? is that correct? i want to extened my hull for extra fishing space. Matt

 

Replace "alloy' with "GRP" and you've got the picture.

 

cdk why would you want 2 jet drives?

-jim lee

 

Sweet. i also want to make a pod that will double not only as a outboard mount but a deck extention 1mt long as i want to cut the transom out and extend to the floor thur to the new transom. Was thinking about making it in aluminum for extra strenght.
Matt

 

I surely don´t, but I didn´t know it then....
See my post on the surface drive sub/forum