Sounds like a great design idea (and present for your dad).
Weird results from a Google search.
Here's a gear in a quilt but it's not paper pieced.
http://thequiltedhen.blogspot.com/se...abel/steampunk
Have you considered applique (fusible would be easy):
https://www.google.com/search?q=gear+cog
Click on images.
You could make blocks of different gears - lot of interesting shapes.
The first few images aren't so detailed, you should be able to easily zig-zag around the edges.
And welcome!