Saturday, May 7, 2011

7 Meters of Greek Key Assembled

Last week Patrice spent some time preparing the material, setting up the jig and laying out the design. All that preparation time was rewarded with only one day required to cut nearly 2000 individual pieces, in 17 different shapes to size. Exact size.

Since we required two lengths and two widths of Greek key for the border of this table top, it was important that all four lengths be exactly the same length; 2.5 meters for the sides of the top and 1 meter for each end. The four lengths needed to fit together precisely at each corner, If each element was slightly off in size, even a fraction of a millimeter, the results would not work.

I have posted the paper (computer generated) design showing the plan, with some details of the ends and center elements. Note the design has a center "T" component on each length where the pattern flips left and right. That change in the pattern is required if all four corners are to be the same. So, standing in the center of each side of the table, the client will see the pattern as a mirror image of itself, with the center "T" creating the flip, left and right. It is surprisingly not obvious unless it is pointed out.

What is not shown here is the two strips of wood, mahogany and ebony, which will be added to the outside of the design and run the length of the table. That will add some width and make the decorative effect more pleasing as well as more in keeping with the size of the top. All the elements are sawn veneer, 1.5mm thick.

I also show the two sides of the assembly board, upon which Patrice built the design, face down with hot protein glue. By using the traditional French method of stretching Kraft paper on a board, it is possible to lay out the pattern directly on the paper first, with pencil and ruler. This allows the assembly board paper to provide an exact scale for the elements to be glued in place. That simple method guarantees that the pattern will end up at the precise location necessary. In fact, the error over 2.5 meters is less than 1/10 of a millimeter.

By stretching the Kraft paper on two sides of the same board, we were able to build the entire pattern on a single assembly board. The next step is to apply mastic (diluted hot protein glue and fine hardwood sawdust) to fill any gaps, and level the surface (which is the glue side). At that point the Greek key is completed, and we can cut it away from the board and apply it to the table top, with the paper on the face. After application, the paper and surface glue is simply removed with cold water and scraping.

By this method it is fairly quick and easy to create a rather complicated running pattern on a piece of furniture.

You can search this blog for more information on the assembly board process.

1 comment:

TIM said...

That looks like it's coming along very nicely, Patrick. I hope you continue to post pics and details of the table as you build it. I'm particularly interested in how you apply the Greek Key border. I'm presuming you'll have to lower the entire field where the key banding is applied?

Anyway, keep up the good blog.

Tim M. (Texas)