While the pumpkin fulfills his destiny on the compost heap I continue working on the settee.
I started off with 3/16" plywood for the templates. However, 3/16" is too thin to comfortably run on a shaper or router when shaping a thick piece of wood. Consequently, I create 1/2" templates off of the 3/16" templates for the side profile of the rear post, front profile of the crest rail (or actually half the crest rail), and the top profile of the arm.
At this point, I suddenly realize that the crest rail template will not be useful as is. The reason is that there is a 1/2" wide rabbet at the bottom of the crest rail (3/8" deep). This rabbet is where the upholstery will be tacked. The template above represents what we will see above the upholstery but the template does not include the rabbet which will be hidden by the upholstery. Now, it is tempting to simply take the existing template and drop it down a 1/2" to include the rabbet. But this will not work! Why? Imagine if the curve of the crest rail approaches 90 degrees. Dropping the template down a 1/2" will not add a 1/2" rabbet where the curve approaches 90 degrees. Where the curve approaches 90 degrees the template would actually have to be moved sideways. As you can imagine, we will end up with a piece of modern art - not a crest rail.
After tea and some cookies, I decided to use my router template set. To be honest, I've had this set for almost 10 years yet have never used the set:
I need to proceed in 2 steps as I do not have a bushing that will give me a 1/2" wide rabbet in one step. I start off creating an intermediary template with a 5/16" rabbet. I first use a wheel marking doohickee to pencil in a 5/16" rabbet. I bandsaw close then take it to the router table:
In the photo above the original template is on the bottom and the new template is on top. On the router table I have a bushing with a straight bit. The distance between the outer wall of the bushing and the bit is 5/16.
Once I shape the new template, I need to shape the top of the crest rail on the new template - the top profile will remain the same so I simply flip the work and run it with a top bearing bit:
Now, I need to duplicate this entire procedure by adding a 3/16" rabbet to the intermediary template with the 5/16" rabbet to finally create a template with a 1/2" rabbet. I use a different bushing to give me the 3/16" rabbet.
In the photos below we see the original template with the new template side by side. The next photo shows them stacked on one another.
Now it is time to shape the rear posts. The rear posts have been jointed and planed to a width of 1-3/4". I do not attach the template yet. I use the template to draw the outline of the profile, bandsaw close, then joint the bottom front of the post - a critical area that is a reference edge and must be flat where it meets the rails:
Now I attach the template and prepare it for the router table. When profiling, I watch grain direction and I keep the router bit from the critical bottom front area that was flattened on the jointer. Oh yes - don't bandsaw too close! I almost did not leave enough wood for the final shaping! Whew, close call.
Next I cut to length. I kept a reference mark on the wood that represents the bottom during this entire process so that during this step the posts would be cut at identical locations - otherwise, the posts will not come out identical.
And they are now ready for the joinery!
For the chippendale chair I built at North Bennet Street School we shaped the rear posts by hand. It was not that difficult. However, if I build this settee again I'll have the templates all prepared and the process will go much faster.
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