I have made working miniature power tools like Power drill, angle grinder, circular saw, air blower…and more with the name of “SAZOH miniature power tools”
Here are the video links of my working power tools
https://www.youtube.com/watch?v=TQumYgobBhY
https://www.youtube.com/watch?v=mTLKdZvh1TA
https://www.youtube.com/watch?v=JCyQfGLsajI
Those are fantastic! You must have a great machine tool collection.
I have a life long ambition to make working models of IC engines. I used to read articles in magazines of guys making such engines. I now have enough tools to start making them, but not yet the machining skills (never took machine shop classes in school.)
So far I have been content with making non-operating replicas of real aircraft and racing car engines (working on 270 Offie now).