Hi Lee welcome!
Like you I also use fusion 360 to design junk (using the term loosely) to fix common problems and issues I run in to (or just random toys to look at). Tell us more! What Filaments have you worked with (aka type PLA, ABS, etc. Also Brands you’ve worked with)? I mainly use Inland Branded Filaments (can buy locally) and have mainly used PLA and ABS (though I have some PETG I haven’t opened it yet). What mods have you done to your printer? Hope you enjoy the forum.