Tinkercad is like the hamburger helper of 3D design. You hate to admit you use it, and you know you should put in more effort, but — darn it — it’s easy, and it tastes pretty good.

First, he adds the necessary pieces to create the hinges to the Tinkercad toolbox. That makes it really simple to add them to any of your future designs. Second, he uses a combination of numeric ...