If it's a simple shape, box etc then that's how Alibre works but if it's say a curved surface like a wing shape it doesn't know where to get the curved surface from.

If you are a complete beginner it's best to learn to use 3D from the start, then you can automatically get 2D from it for a CNC etc.

Going from 2D to 3D is a lot harder because you have to unlearn a lot of how you work and learn new ways, old dog , new tricks etc.

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