Tools for creating mechanisms and boxes

Hi,

I am looking for your best tools, resources, etc. for making various mechanisms. How do you make gears (regular, rack, etc.), cams, linkages, sprockets, etc? Also what ? What (free) software do you use? Ideally, I would like tools that work in Linux.

I’ve found some online resources, but I’m wondering what creative or other solutions people use?
https://woodgears.ca/gear_cutting/index.html

Thanks for any/all suggestions!

Josh

I usually don’t do this, but here is another Gear generator I have found helpful.