Extend stringers through transom for hull extension

[bradz]

Hi everyone.

I've been reading this form for quite a while but have only joined up today. What a great source of shared knowledge.

I'm in the process of rebuilding a 19ft Regent Viscount (West Australian fibreglass boat). So far I have gutted it. Floor and stringers all gone. My plan is to reinforce the hull with a few layers of CSM and Biax, put another layer of marine ply over the inside of the transom, rebuild the stringers (2 laminated 18mm Marine Ply) and floor and then bolt and glass on an outboard pod which follows the hull profile. I guess you'd call it a hull extension. It wont be full width...just about 2.5 feet wide.

My question is this; after building the extension I was simply going to bolt and glass it onto the transom. However, I've seen a few (not many) instances where guys have extended their main stringers through the transom and then built the extension around the stringer. I would image this would be extremely strong, and rigid. Is there any good reason why this is not used more often? If my boat is already gutted, surely making the stringers 2 feet longer and cutting vertical holes in the transom would be a very sound, strong and secure way of achieving the same result.

Any feedback would be greatly appreciated.

 

[ondarvr]

It will work either way, so pick a method, I'd go with the easier design.

 

[tpenfield]

The challenge that I see will be to make the joints where the stringers protrude through the transom strong enough so that flexing does not lead to separation cracks and result in water penetration and eventual leaking of water through the transom.

 

[Grub54891]

First, Welcome to I-Boats, If put through, and properly tabbed in they should be pretty strong, However, the top of the pod is the one I'd want even more strong myself. The torque from the prop pushes the bottom in, the top pulls out, lifting the boat. What size motor ya have for it? I'm sure others will chime in in with opinions.... Have fun on the rebuild!

 

[bradz]

I will most likely have a 150hp Honda 4 stroke.
Having lots of fun (sort of) with the rebuild.
If I can't determine a definitive benefit I will simply bolt on and glass the extension all the way around.