I removed the transparent plastic piece to put the compass-like piece.
I wished the brass bolts were philips not straight.
I drilled the hole for the center-piece for the compass. I started cutting and making the half circle.
I wanted to play with a different radius so I connected the one end with the other arc that continues.
So I gently hammered from the outside and made those teeth present inside.
Now, I was back to business cutting arcs.
I set up the jigs to cut the straight line by placing the router on each ends.
Cutting on the edge of the ruler for the first time was little difficult because I did not expect its movement.
It was more like cutting with free hands without any guide. So later I got used to pushing the router to the ruler while cutting.