Grooves are now milled into the stringers, into which the steps and risers are later inserted. This requires a high degree of precision so that all fits fit later and the stairs do not creak. In the past this step was done by hand with a chisel. Today, hand routers are used for this. However, the process is still often referred to as mortising. The corresponding construction variant of a staircase is called mortised staircase.
There are hand routers that are specially designed for building stairs. These have templates and fixtures for precise positioning of the milling cutter on the stringboard. Sufficient power and sharp tools are essential for milling the most commonly used hardwoods.
