toy size submarine; that can float and sink on its own?

Question

how do i build it? it has to have a 12inch living space... stelling me ites would be a great help

Answer 1

that would be kind of hard to make the float and sink feature, you have to have something on it to allow you to change a space between vacuum and water, like

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when u want to sink and

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when u want to float, maybe a pneumatic or something

Answer 2

Well I would love to stell your ites but unfortunately there are State laws about that sort of thing.

If you can explain the project a bit maybe I / we can help. For example.

1) What is the goal
2) What materials are you allowed to use.
3) How deep must it 'dive' (pressure considerations)
4) How is it expected to manuver ?
5) When is your due date?
6) Is your 12" space the exterior dimension or the cubic inch hollow space)

ok?