Abstract: A construction for wooden stairs that permits standardized, factory machined components to be pre-packaged and shipped to the job site where they can be installed to fit almost any installation. The structure includes stringers which have riser and tread receiving grooves on both sides. The grooves on each side of the stringer provide for a different rise and run rate. The construction technique and the resulting stairs substantially reduces the job-site layout and assembly time from that required with conventional stairs. It also reduces the number of components that must be produced and stocked. The technique is especially applicable when employed with wooden stairs of the interlocking type that generally need no fasteners, adhesives or wedges.

Abstract: An apparatus that facilitates the manufacture of wooden stairs of the type having treads and risers extending between and affixed to side housings or stringers. The apparatus provides multiple, parallel guides for the router used to cut the grooves in the stringers into which are fitted the treads and risers. By using a parallelogram construction for the multiple guides, the apparatus can be quickly adjusted and set to produce almost any size of stairs. An index bar used with the apparatus allows the apparatus to be quickly set for the particular stairs desired so that the grooves for both the treads and risers can be cut quickly and accurately in the stringers. The router is moved along each of the parallel guides to cut the grooves for all of the treads, and then the apparatus is quickly and easily reset and locked into position to set the guides for cutting of the grooves for the risers.

Abstract: A construction for wooden stairs that provides for rapid layout and assembly of the stairs by using an interlocking technique that locks the treads and risers into the stringers without the use of fasteners, adhesives or wedges. The construction technique and the resulting unique stairs substantially reduces the layout and assembly time from that required by conventional stairs by accurately machining the required dovetail grooves in the stringers and the corresponding male dovetail on each tread and riser end. Each tread and riser are then slid into place in the stringers and are interlocked so that once the stairs are assembled and interlocked, it is impossible for the components to become separated.