I designed this jar withhttp://shapeshifter.ioand modified it a bit with Autodesk 123D Design. Then I used the Microsoft 3D Model Repair service (http://modelrepair.azurewebsites.net) to repair any potential problems.
My first 123D Design. Wanted to create a tutorial to help people learn how to model for 3D Printing. Used a "free" software 123D Design. )http://www.123dapp.com/design)Tutorial can be viewed here:http://youtu.be/wdFbzZ8o5VoDISCLAIMER: Slingshot is for educational use only. Please do not use designs to harm any people, places, or animals.