I have gotten some good use out of my router radius templates. I saw an interchangeable jig system that did a similar job and included chamfers in addition to the radii. First a reminder of how they work. You sit the template on top of the wood and use a special router bit that is a cutter with a matched diameter bearing on top. The bearing follows the template and removes any wood that protrudes beyond it. Ideally you cut off as much waste as you can on the bandsaw or elsewhere. Routers don’t remove a lot of material well.

I modeled a variety of them from 0.5″ to 1.25″. The length given is a leg of the isosceles triangle that will get removed, not the hypotenuse. See the diagram below.

I printed a stack of them in case the need arises, and uploaded the design to thingiverse. If they look odd compared to my normal prints, it is because I used some cheap translucent filament I had lying around. I figure they will get torn up eventually, so no need to use the good stuff.