A routed groove adds interest to flat-panel doors, but finding a way to radius the corners was a mystery to me. This router subbase changes that. First, build a router subbase from 1⁄4" Baltic birch plywood in the shape of an equilateral triangle (one with three equal-length sides). Keep in mind, the distance between the router’s bit and the triangle’s sides equals that between the door’s rails or stiles and the decorative groove. Use the door’s rails and stiles as guides for the subbase…
Cut perfect dado grooves with this jig. How to use your router and this jig for cutting dadoes.
Jig for straight cutting with a router. Very simple and useful
DIY router Circle Jig
Fluting Jig Woodworking Plan, Shop Project Plan | WOOD Store. For the stairs treads.