Hull Extension/Lengthen

[JEV1]

I have a 1971 Marinette 28' how much can i stretch it. I was told by others i could go as much as 12' as long as i do it at the widest point and then redesign the cockpit as to get the balance right Has anyone heard of this before. Does anyone have any helpful input. thanks

[Ad Hoc]

The first thing you need to consider above all else, is the affect on stability and then strength.

All that to one side, so long as the total mass you are adding (outfit, structure etc) is less, or equal, to the increase in voulme you are getting with your 'extension', you will get the same speed.

[JEV1]

how would one figure this out. I am a good tear apart and fabricate and duplicate type of guy. i was told to take it apart from one support beam and basicaly cut the ship in half add the 10 foot section by way of duplicating the exact spacing and bracing as was done at the current design. so it would then be a 38' loa by 10 beam.

[Ad Hoc]

If you can, get a local NA to 'eyeball' it for you, if you are totally unsure. Since without seeeing any pictures, dwg's or knowing any of the parameters of the boat, impossible to say.