Since the focus is on cutting square holes lately, here is a bit about that on my project. On this design the operating lever is connected to a part called the toggle link. You can see this part is the earlier picture posts. Well as this link rotates up into the floor plate it slides up into a square mortise that is at a 15 degree angle. This is about the most difficult part of the action design to make. Today I cut that mortise at its 15 degree angle. I have attached a couple pics of the operation. I first milled out as much as I could and then used a broaching tool mounted in the Bridgeport quill to shave out the square corners. After the toggle link and floorplate are all fitted together I will post a finished pic.
[Linked Image from i.imgur.com]
[Linked Image from i.imgur.com]