Last week I finished making the form that I would use to create the curved panels for the carcass of the cabinet. The next step is to create a curved substrate that I will eventually veneer with the woods that I choose for the project. The substrate is create by gluing together four layers of bending poplar or wiggle board. The bending poplar is a special plywood about 1/8 thick that is very flexible in one axis but stiff in the other. The reason that a plywood is used as the substrate is that it will not expand and contract like a solid wood substrate. This means the door is unlikely to change shape or size as the weather changes.
Creating the substrate is straight forward. Cut a few sheets of bending poplar to size. Cover them with glue. Set them on the bending form and place them into a vacuum bag. Suck all the air out of the bag and let the weight of the world press the layers against the form to create the desired shape.
Once the glue has cured I slide the plywood core off of the form. I will need to cover the edges of the new plywood with something pretty so that the plywood does not show when you look at the top/bottom edge or side edges of the doors. These are called edge bands and they can be straight pieces of solid wood glued to the vertical edges of the door panels, or they can be curved pieces of wood glued to the top and bottom curved edges of the door. To make the curved edge bands I use a similar process but instead of bending poplar I use thin and narrow strips of solid wood and bend them around the form. If you look closely at the photo you can see the top and bottom edge bands at the far edges of the form. I had to use a clamp in order to get a little bit of help bending the last few inches of the edge band to meet the form. Those clamps are foreshadowing of a learning opportunity I will experience next week.
If you have been following along and any of this is making sense, you are probably wondering exactly what type of solid wood I have in the vacuum press for those curved edge bands. You would be correct in the assumption that I have made some final wood selections for the project.
I spent a good part of week 3 in the wood room and the back room at The Krenov School looking at various planks. Pear was suggested by one instructor and the thought of a nice even creamy texture and tone was very appealing. Old growth Douglas Fir was the suggestion of another instructor and the thought of the tight grain accentuating the curves of the cabinet was also very appealing. There was a plank of Curly Eucalyptus that is absolutely stunning but probably a little too crazy for the outside of the cabinet. I have a plank of Eastern Swamp Ash that I picked up in Michigan while driving across the country this summer.
Suddenly and not unexpectedly I was trapped in plank purgatory overwhelmed by the endless options for the cabinet that I might build. Late in the week as I was rummaging around my workbench I came across a stack of Spalted Sycamore veneers that I had cut on the last day of school last year with fantasies of some summer project. They had quite a bit of vertical character like the Douglas Fir that would show off the curve of the cabinet and they had a whole bunch of crazy drippy graphics like the Curly Eucalyptus. I thought they looked great and I had plenty of them.
The Spalted Sycamore looked great on the carcass but was not an option for the top of the cabinet. I wanted something rich and homogenous and complemented the colors in the Sycamore. Back to the wood room and more digging. Another day in plank purgatory and in another bout of frustration I rummaged around my workbench and came across a piece of mahogany that I had used last year to test various finishes. I held that up to the Sycamore and BAM!, that looked pretty darn good.
At this point I could not discern if the beauty of Spalted Sycamore and Mahogany combination was due to serendipity or exhaustion. I decided I would head to Kinkos over the weekend and do some digital printing so that I could hotrod my mockup next week.