Cliff Rohrabacher
10-13-2007, 4:10 PM
This is a new experience for me. I am gong about the business of learning to design and build a Chippendale chair. Working from pictures of chairs I have the basic dimension and angles down.
The seat is an isosceles trapezoid when the chair is done the rear legs will have a 20 Degree included angle being narrow at the floor and at the top being much wider: about 2-feet apart at the top. The rear legs will also be angled out of parallel by 10-degrees included top accommodate the angles described by the seat.
I am using a 78.5” radius for the sweep of the back leg posts. It’s a radius whose center begins 14” up from the floor and cants off at 10 Degrees and sweeps the full length of the rear post. That was the easy part. I got to use my beast of a torsion box for the first time. I am glad I made it heavy~!!
Then I did the mortises for the seat rails and the lower front to back side stretchers. That was easy too. I made a 10 degree block of MDF and canted my shop made mortiser head off at 5-Degrees (5-Deg being the angle the seat will splay outward to the front of the chair) and used the plunge on my router like a quill on a miller to get the depth of cut.
Oh goody I have two roughed out rear legs. Ain’t I special~ ~ ~ ~
Then I made the side rails with their tenons.
Now I went to inset the tenonned side rails into the rear legs to see just how much the combination of (1) trapezoidal seat angle; (2) radius of the rear leg; (3) cant of the rear leg; all work together to frustrate my getting the tennon and shoulders to fit correctly. They do a marvelous job of not letting the shoulder seat correctly on the post. They look terrible.
Now I have to figure out how to get that surface where the shoulders of the seat rail tennon must lie in order to be flat and at the correct angle. I think I need to build a shooting board. I think that a shooting board will let me lock the leg in a fixed angle & use a hand plane to shave the stock off slowly so I can see it develop so that it’s just right. Either that of a fixed jig for the Jointer
<<< If any one has done this don’t be afraid to jump in and tell me what you do >>>
As I think through what Ive done so far I wonder it it wouldn't have been easier to make a router jig to get all the angles and curves in one pass and obtain flat surfaces as well.
The seat is an isosceles trapezoid when the chair is done the rear legs will have a 20 Degree included angle being narrow at the floor and at the top being much wider: about 2-feet apart at the top. The rear legs will also be angled out of parallel by 10-degrees included top accommodate the angles described by the seat.
I am using a 78.5” radius for the sweep of the back leg posts. It’s a radius whose center begins 14” up from the floor and cants off at 10 Degrees and sweeps the full length of the rear post. That was the easy part. I got to use my beast of a torsion box for the first time. I am glad I made it heavy~!!
Then I did the mortises for the seat rails and the lower front to back side stretchers. That was easy too. I made a 10 degree block of MDF and canted my shop made mortiser head off at 5-Degrees (5-Deg being the angle the seat will splay outward to the front of the chair) and used the plunge on my router like a quill on a miller to get the depth of cut.
Oh goody I have two roughed out rear legs. Ain’t I special~ ~ ~ ~
Then I made the side rails with their tenons.
Now I went to inset the tenonned side rails into the rear legs to see just how much the combination of (1) trapezoidal seat angle; (2) radius of the rear leg; (3) cant of the rear leg; all work together to frustrate my getting the tennon and shoulders to fit correctly. They do a marvelous job of not letting the shoulder seat correctly on the post. They look terrible.
Now I have to figure out how to get that surface where the shoulders of the seat rail tennon must lie in order to be flat and at the correct angle. I think I need to build a shooting board. I think that a shooting board will let me lock the leg in a fixed angle & use a hand plane to shave the stock off slowly so I can see it develop so that it’s just right. Either that of a fixed jig for the Jointer
<<< If any one has done this don’t be afraid to jump in and tell me what you do >>>
As I think through what Ive done so far I wonder it it wouldn't have been easier to make a router jig to get all the angles and curves in one pass and obtain flat surfaces as well.