I've been 3D printing slinkies (helical coils) and I used build123d for it. Somebody on HN recommended it as a first pass if you don't know CAD.

It's a little rough but I was able to get it to do what I needed it to! Here's my code: https://github.com/freeqaz/light-coil-model

Let me know if you want one. They're pretty rad!