To make the lines for the front and rear bolster I used a long ruler and the hole in the ruler sitting on a finishing nail in my workbench. Set about 10-1/2 inches from the spine it will make an arc. The front line I kept at 90° to the spine.
Swing the ruler on the nail over about 25° and make the rear bolster line.
This is the idea in a graphic.
Now for marking the half way line.
And marking for scale pin holes. These are center and 1/2" in from each end on the line. I also mark the holes for the hidden pins on the both the front and rear bolster.
Punch before drilling.
Annotate so I get the right bit. :-)
Drilling on the drill press with a dash of cutting fluid.
I added some extra holes to reduce the weight of the handle area. This will have stainless bolsters which will add weight to the finished product.
Tapping to 8-32 for the blind pins.
Ready for a quick sanding, foil wrap and heat treatment.