When you start programming, or pick up a new programming language, often the first program you write is referred to as a “Hello, World!” program, because for the most part all you want to do is be able to produce a working program, so printing something like “Hello, World!” to the screen often feels like a great start. Once you have that working, you can expand upon it.
So we have a MOD-t 3-D printer that we bought a couple of years ago, and I’ve printed a bunch of things on it, but they were all things that other people designed. I’d always wanted to be able to do my own designs, and had two particular projects in mind. One is a part of a cover for a Starbucks travel mug. I have one that I really like, but the small piece which closes over the mouth hole keeps coming off. It doesn’t really stay in the cover, and is constantly at risk of being lost. So I’ve wanted to create a replacement. But that would seem to require considerable design skill. On the simpler end, I have a portable phone charger that I carry, which doubles as a flashlight. I like it, but periodically the light will come on in my pocket, and I may or may not notice. If I don’t, the battery will die. So I’ve wanted to create an end cap for it, to protect the switch from being pressed accidentally by all the other things in my pockets.
And so I have! I created such a cap using the program OpenSCAD which allows you to design things by describing them with code. For this particular item, it is essentially 3 things: a pretty flat cylinder for the base, a hollow cylinder for the body, and another hollow cylinder that sits just inside the larger one, which is very small to make a tiny ridge inside the body, enabling the cap to “snap” fit on the device at its seam. On the 8th try, I have something I am now happy with: