For example, I wasn't organized enough to save all of my failed prints (there were quite a few and I just tossed them). But Matt did, and he proudly displays them in his post:
Many of his tips are ones I discovered myself while writing my SketchUp for 3D Printing book, such as leaving enough tolerance for interacting parts, printing test runs to make sure interacting parts will fit, rounding corners for extra stability and strength. Other tips are more technical, like checking G-code manually. (I generally left the G-code writing to the printer itself.)
One of his tips that I hadn't thought of before has to do with grain direction - the angle the printer uses when laying down each layer. Generally printers will place one layer using a diagonal grain, the next layer using a diagonal grain in the opposite direction, repeat. These joints between layers can become a point of weakness and lead to warping. For optimal strength, Matt says:
A way to overcome this potential problem is to simply orient your model so that the X/Y axis plane is where you need the most strength. Layers print in the Z axis direction. Continuous extruion happens along the X/Y axis plane, so they are stronger.
Useful stuff! If you have a 3D printer, be sure to check out Matt's advice.
Anyone can design anything in 3D! http://www.3dvinci.net/