3D Printing allows you to literally print a real object that you can pick up. It is a great tool for prototypes and getting an idea for the fit and form of a design. A real "thing" is so much better than drawings.
It does have limitations though, so please read through the Design Considerations below so that you are set to succeed.
When designing your model, please take the following into account:
• Dimensions must be less than 120mm x 120mm x 120mm (4.72").
• Models must be a Manifold.
• Minimum layer thickness is 0.25mm (0.1").
• Walls can go down to approx 0.8mm (0.0314") thick.
• Walls will not always be solid due to the way filling works.
• Allow for +/- 0.5mm (0.2") tolerances.
• Warping can be a problem on deep / wide models (>~80mm).
• If in doubt, consider a small test print or contact me.
This calculator and the printing software need your model to be in "STL" format. The calculator assumes that the STL has been created in mm, so please be sure to convert designs in other scales (inches / cm / etc) into mm before submitting. Blender supports STL export natively and a plugin is available for SketchUp. Most commercial solutions also have an STL export facility.