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.
Two hobbies collide as I print something super nifty for my wood habits. A cool thing you can do with router tables is apply a template onto wood, and use a templating bit to match cut. The bit has a bearing of the same diameter as the cutting edges. It rides against your template and cuts away any underlying wood that isn’t shaped like your template. Super handy, but you need a good template to start with. Enter the 3D printer.
I modeled up this little jig so that it hooks onto the edges of a board and gives an exact radius. It is hard to see given the color, but I printed a 1″ text in the bottom to note the size of the radius.
Here is a picture of the jig fully seated, and what the resulting cut looks like. Very clean and smooth. The large circular cutout gives a lot of finger purchase so you can hold it tight and far away from the spinning bit.
One concern I had was with the material. Would the cutting friction heat up enough to melt the plastic. I did 4 cuts on a 3/4″ bit of plywood and everything looked good. If I had a hundred corners to do, I would worry. I could always upgrade to PETG.