Sunday, August 10, 2008


Maybe its the scale or the lovely gray of the weathered beams, but the finished shed frame reminds me of an elephant. In one of the books that I read to learn timberframing, they used the analogy of a timberframe supporting the building like a skeleton, where as modern framing is a rigid skin. One look at this says it all.

There are some similarities that I've come to enjoy between timberframing methods and chairmaking. I spent the last week teaching Ernie Palmieri to make a continuous arm. Ernie has been a woodworker longer than I've been alive. He's built everything from houses to fine furniture (including a rocker that he completed before taking my class). We spent a lot of time laughing as Ernie learned some of the more "organic" methods that can be employed in making chairs from trees. It's a whole different type of precision. He would laugh whenever I said that we were going to "eyeball" the work. On a couple of occasions I reminded him that squares and tape measures are read by "eyeballs" as well!

The great departure from standard woodworking, by which I mean the kind where parts can be made from a plan and then be interchanged in assembly, is that in a chair, you build to the chair, not the plan. Pieces become assigned locations and the process must take the actual shape of the existing pieces into account to determine the next step.

In timberframing, the beams are not cut to standard dimensions. To my sawyer, a quarter inch here and a half inch there are pretty much standard. The beauty of the timberframe process, is that the layout of the joints enables the builder to work beyond standardization, which I find to be quite graceful.

Here is a beam mortised into a post. The concept is the same as in woodworking, but with one difference. Instead of planing the post to a standard size, I simply notch the shoulder of the tenon into the post far enough to leave a standard 4 inch thick piece. It is by measuring from the depth of this notch that I can determine the length of the beam. A four inch post on both sides adds to eight inches, subtract from the overall length desired for the structure (twelve feet) and I know to cut the tenon shoulders eleven feet and four inches apart. With this creation of references, I soon came to understand how an entire structure could be made using logs that were flattened and squared on only two sides. How's that for "organic"!

Here is the one part of creating the layout that may take some real headscratching before diving in. The cross bracing is meant to control wracking by preventing compression. Often, they weren't even pegged. With all of the extra wood hanging around on the posts and beams (not to mention the braces themselves), finding the correct references to create the triangle and determine the length of the hypotenuse can be a challenge. I laid out string to show the actual geometry. You can see that based on the references used, there is a logic. I found a book by Jack Sobon to be incredibly helpful in learning to get exact dimensions from inexact timbers. If it weren't for the intense physicality of the process, I could see being happy as a timberframer, it is a great challenge, but I prefer being able to lift my product easily over my head. So chairs it is...

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