This is my version of a loose tenon mortising jig. It is a combination of several single purpose jigs and takes advantage of the router guide micro positioning when needed. I didn't get a good picture of how the edge guide is captive in the T slot at the back.
Vertical or horizontal pieces. Vertical piece length limit is overcome by repositioning the jig to be horizontal. The 45" slot is engaged by the lip on the edge of the "fence" to locate a 45" angle quickly and accurately.
Notice that the slotted fence fixture (seen everywhere in my shop) is the basis for the lateral action. Setup is centerline driven, so those stop blocks are usually equidistant from the centerline, each on their own ruler.
A unique feature of this jig is the tilting table that uses no hinges. The square plywood panels at the ends form a trunion action that lets the pivot point be precisely at the intersection of the bottom plane of the router and the face of the slotted table. This is handy for setting up compound angles.
Back side view to show how it is clamped to the bench through the dog holes and the T slot at the back where the edge guide is captured.
Dan is an experienced woodworker who is anxious to make an heirloom of the future for you.