Some free 3d programs to create model that for 3d printers, or cardboard cutout models;
http://www.123dapp.com123D DesignDesign the thing you want to make, and send it straight to a 3D printer.
123D CatchAutomatically convert ordinary photos into extraordinary 3D models.
123D SculptShape and paint digital clay into amazing 3D sculptures on your iPad.
123D MakeTransform 3D models into a pattern for assembling real artful creations.
Apps available* for
* mac
* pc
* ios
* web
* not all apps available on all platforms.