Using my Sketchup model as a reference I drew the shape of the corbels onto the prepared stock, and cut it out roughly on the bandsaw. Then with sandpaper and a card scraper I smoothed them out to their final shape.
I forgot to take a photo of the setup for drawing the arc, but basically I bowed a piece of plywood to the correct vertical distance at the center point of the arc and traced the curve with a pencil. Cut it out roughly on the bandsaw, and smoothed it out with sandpaper.
The mortises will be done with my benchtop mortiser, but before I drive out to my brother’s shop I need to spend some time marking out where the mortises will be.
Step 1: Mark the height of the mortise using the actual tenon as a guide.
Step 2: Use a marking gauge set to the distance of the cheek of the tenon from the face of the tenoned part to mark where the face-side edge of the mortise will be. This will ensure that the faces of the parts will be flush to one another when you assemble them.
Step 3: Hold the tenon in place and draw the opposite edge. It’s always better to use the actual part for this measurement. Introducing a ruler at this point is an unnecessary step that can introduce errors. If the goal is to make a square hole the exact size of the tenon, the use the tenon as your frame of reference.
Step 4: Hold the tenon in place over the mortise-part like so and indicate the depth you’ll need the mortise to be. This mark will come in handy when setting the mortiser depth stop.
Extra Step: If you screwed up one of the tenons by cutting on the wrong side of the line, like I did, and it’s a little smaller than the other one, make sure you mark it clearly and keep track of it the entire time. It’s not a mistake if you hide it inside a perfectly fitting mortise. :)
Step 5: I didn’t bring my camera to my brother’s shop, but drilling the mortises is pretty straight forward. It’s a square chisel with a drill bit inside of it. It drills square holes. For the through-mortises I drilled from both sides to prevent grain from spelching out and ruining the look.
perfect, my best fitting through-mortise & tenon yet
I used my brother’s router table with a straight bit to make the double-stopped rabbets on the stiles. I’ll chisel out the corners by hand.
And here’s the final dry fit. The tenon shoulders need a little tweaking to remove the gaps and bring everything in nice and tight, and I’ll probably relieve some of the tenon cheeks so the fit is a little easier so I don’t run into trouble during glue-up.
-- I've been creating problems to solve since I was born.