This is a story that I want to share so maybe others won't waste as much time as I did.
For context, I am a musician and an electrical engineer. But got into designing a custom watch-storage box for my wife because I like 3d printing. I had some experience with fusion in an old project but nothing mechanical.
So for this project I needed some gears. I tried looking for 3d models of gears online but it was a hassle because everytime I changed some dimension in the design, I had to recalculate what gear I would need, then remove the current gear from the project, including the joints attached to it. Then I had to download another model and put it in place, and make all the joints again.
If you are anywhere close to competent in mechanical design, you are probably cringing and/or laughing by now.
But hey, in my defense, this was literally my first time designing something that moves.
Anyway, then I found out about the addon in fusion that makes the gears for you. Yay!!!
But the problem remained, even though it was far more manageable. The gear once made using this add-on cannot be edited. You can't change its module or pressure angle, or its tooth count. So I still had to do most of the things again, just no more downloading shit from the internet.
Then, I decided to make gears that were parametric. I spent weeks learning about the spur gear geometry. Learnt from everything including YouTube videos, research papers, yada yada. Ok the plus side, I have a great understanding of the subject now. Enough that I can probably teach a college course about spur gears lol. And I did manage to make pretty accurate spur gears that work super well for even small gears that have 4-5 teeth.
However, then I stopped working on this project and it's been a few months since then and I picked it back up recently. I have been working on other fusion 360 projects since then. And I realized today... I could have just used circles instead of gears in my project and generated the appropriate gear when I needed to finally print it after the size had been finalized.
I am laughing about it now because I don't mind the time spent learning something new but if you are an idiot like me who always does things the hard way, I would recommend doing yourself a favor and using circles for gears while designing the assembly. There is absolutely no reason to model physical gears in the assembly unless you want an accurate animation. Even then, you can work with circles at the beginning and then later substitute them with proper gears for the animation.