When i stand up its look like the physic oh my boat become convex hull, is it possible.

[Alwin Alcott]

you asked something simular a while ago... https://community.secondlife.com/t5/Technical/i-just-made-a-mesh-boat-with-physical-when-i-run-it-its-ok-but/qaq-p/3059177

[Alwin Alcott]

you asked something simular a while ago... https://community.secondlife.com/t5/Technical/i-just-made-a-mesh-boat-with-physical-when-i-run-it-its-ok-but/qaq-p/3059177

[Rolig Loon]

Thank you, Alwin, for reminding me of the OP's previous thread.  I just went back and discovered that he has edited it with more information.

It looks like the boat has been made by dropping unrelated pre-made scripts into it instead of writing scripts that were custom-designed for that particular boat.  There's no reason why it should make any difference whether the boat is convex hull or prim (except for its L.I., obvously), and you could write scripts to make it rock and bob whether it was physical or not.  I'm guessing that the pre-made scripts are conflicting with each other to produce some odd effects.  The best solution is to replace the scripts or at least hire a scripter to sort them out.