Here we tackle a typically tough thing, the Full Bonnet. I have seen and done this many ways, none were really to my liking, the orginal had a thin veneer nailed over a sub-structure, and many are done that way, personally I'm not a fan of all the nails. Rarely have I seen full bonnets that were not cracked. When attached to the sub-structure like the original (which was cracked), the technique hinders expansion and contraction of the case sides. So here we are doing a new thing, we are "coopering". We are using approx a 5/16-inch thick pieces of mahogany. We cut it into narrow strips and then we are gluing them to the poplar substructure which is nailed to the scroll boards. Note that the poplar is not full width, it is approx 3/16-inch narrower and simply nailed in place. The nails will allow the case sides to expand and contract as nails will flex. When the mahogany is glued to the poplar, care is taken to not glue it to the case, only the poplar, this again will allow movement. Also note the straight edge clamped to the case and the use of the combo
square to help determine the angles. To fit all of this together tightly we actually used a wide piece of mahogany and kept it in sequence so as to get the best grain match possible. We used some 5/4 lumber but 4/4 will do. We re-sawed all of it so one piece of wood did both sides. We are "walking it up so we can get clamps on easier. When all is said and done, we will hand plane and maybe a little spoke shave all the surfaces smooth. Yes, we will have numerous glue lines so fit it as tight as possible. If the glue lines are an issue, you could apply a sheet of veneer over the entire bonnet, however, if you take your time and fit it well it will look great and produce a sound and solid bonnet free of visable nails as well allowing for expansion and contraction. The end grain edges will be covered by the gooseneck mouldings. An alternative would be to use thicker material ( 4/4 or better) and shape the bottom to fit the curve and then shape the top. This method would produce less glue seams but more time and material.
We also simply nailed together a small box that will sit under the bonnet and above the top right and left drawer. The box will be quietly tucked away as a neat secret compartment. To get to the hidden compartment, you wil have to remove the side drawer as well as the center, just one of those fun things. This is one of my own things I have added and was not in the orginal.
Ok, we will keep on building. The bonnet is one of those things that slows things down a bit but is a “glad thats done” accomplishment! This will also allow the bonnet to fully dry well before we final shape it when we get back to the Bombe March 1st.