After making the keys and forming all the the mortises, I made the dowels.
To make a dowel I first used the band saw to re-saw and form a square shape rod. Then I forced it into a hole in a dowel maker (dowel maker in a steel plate that has tapered holes in deferent dowel diameter.
I found out that some woods, like Bubinga or Heard pine, will not shave so nicely while others, such as birch or maple will be easier to form. However, I choose Bubinga for its beauty and contrasting effect on the oak.
I glued half of each key into its dedicated mortise.
After the glue dried I drilled a hole that passed from one face of the board to the other, penetrating through the key. Than I inserted the dowel to secure the key – just in case, and for appearance purposes.
Then came the crucial part of drilling and alighting the holes on the other side of the board, so that once the dowels are inserted the it will force the joint between the boards to close; enough to make the dowel to spring and pull the key inside the mortise and consequently the edges tighter.
I started by drilling the boards (to prevent fibers from the inside of the mortise walls form blowing out, I inserted a sacrificial floating tenon while drilling).
Than I inserted the facing boards and its keys to the mortises and marked out the circumference of the entry hole onto the key.
The next step was to indent an of-center point on the marked out circle. I drilled the of-center hole, brushed glue in the mortises, on the keys and on the edges and pressed the parts together. Then I drove the dowels in (with some glue) and saw how they pul the joint tight.