"YHT Rule" for learning of FDM 3D printer

Many people prefer to use FDM 3D printer because it is cheap, simple and easy to handle. To get good quality output, there are some facts to consider in modeling. It is "YHT Rule" for FDM 3D printer. I got the modeling idea from here. http://joes3dworkbench.blogspot.kr/2014/05/3d-printing-tip-designing-with-supports.html

Y is good, H is soso, and T is bad.

This model was made by Tinkercad.

Tutorial videos to learn Tinkercad: https://goo.gl/lUWhrq

Making & 3D printing by Tinkercad: https://goo.gl/iWpt4x

And I made a short video for the student who wants to know about 3D printer. Share alike and show alike.