Monday, May 2, 2011

The Gallery cabinets continue...

Well, the gallery cabinets are starting to roll now. The flat parts are nearly finished being cut, and the curved pieces are almost finished being glued up. The curved parts are all shaped using bending forms. I ended up making 6 different forms for the 8 types of parts needed.

For the toe kick fronts, the forms are simple - multiple layers of MDF with a curved edge, The 2" wide kick fronts are glued together by simply clamping the glued parts to the form ....



The curved display case fronts, though, require more complicated forms. The forms are made of ribs cut to the required radius, which are then joined with cross-braces and solid wood ends. This frame is then skinned with a layer of bending plywood....



Since the edge of each cabinet front layer will be shaped, the layers have to be veneered and bent separately before shaping, then the layers joined together. To maintain the correct radius of each successive layer, all three are glued up at once. It's a little tricky, but with a system, it works fairly smoothly. In a nutshell, each glue-up requires 7 components - the main layer is made of two pieces of bending plywood and a veneer covering, and the two outer layers each consist of one piece of bending plywood and one of veneer - after glue is applied to all surfaces, each layer's veneer and substrate are taped together to keep things from shifting .....



Next, the three layers are stacked and filler strips are added to maintain an even thickness throughout the entire packet. A hardboard caul is then added, and the whole packet is taped down to its form .....





Then the whole thing is put into a vacuum bag and pressed ....



You might also have noticed the big chalk arrows on the veneer faces - those are to help maintain a consistent grain direction an all parts. One of the great properties of the khaya (a type of African mahogany) that I'm using for this project is that, like all mahoganies, it has great luster, but the luster is directional. Meaning that if you were to rip a piece of wood into two halves and flipped one 180 degrees, the two halves would look different in terms of color (one being darker than the other). This is due to the directional nature of the wood fiber cells, and the way light refracts entering and exiting the cells. So, for a consistent look, its important to make sure all the cabinet fronts have their grain running the same direction - hence, the arrows!

Stay tuned .....