Computer aided design

This week I tried to model my project, with number of programs,
DraftSIght,Rhinoceros,and 123D DESIGN I installed theme on my computer
And start to experiment with a 2D sketch of a ball .

The program I found most easy is 123D DESIGN
I sketch a half circle in 2D.

After that i use the option called revole.
Now I enter 180 deg and Get a 3D half ball, then I use the shell option.
Now I have only the shell of the ball.
Now I work on design of the shell I choose circular pattern,
And then enter the number of balls I wanted.
The program is pretty friendly and in a day I got the hang of it
And started to play with some weight design.
And then I just started playing with it a bit.
You can see the printed results week 5.