I am very interested in the pins (rivets?) that are attached to the flat straps which are then pinned through the queenpost. The drawing implies an oblong shaped slot presumably shaped so that the strap portion could be slid up through the beam, then the head of the rivet is large enough to overlap the sides of the slot for bearing so that they are not pulled through.
A very small chain mortiser might make easy work of the slot, I suspect they did something different, any thoughts on how this might have been accomplished?
Surprised no one has taken a stab at this one. It's a great question.
My guess is a drill started it, then maybe a long narrow "keyhole"-type handsaw? Or maybe a file/rasp of some sort??
