Cutting The Seat Shape

You are now ready to shape the main profile of the seat. For this, you will use three tools and you will get a feel for where each one works best.

Taking the bulk - Saw

The most efficient way to take off the bulk of the waste is to saw down the four corners. This will leave you with an octagonal shape, which is closer to the circle that you’re ultimately after. Use the 45° angle on the combination square to mark four diagonal cut lines tangent to the circle. Then, clamping the seat in the vise, saw down each of these cut lines, taking care not to cut into the circumference.

Note: Remember that all of your markings are on one side, therefore you must try to work as accurately as possible so as to avoid drifting out of square from one face to the other.

Cutting to the line - Chisel

Once all four corners are cut off, use a wide chisel and chisel hammer to split cut/chop off the waste. You’ll want to work more closely to the line, but still take care not to cut below the line or take too much off towards the opposite face (where you have no layout markings).

As you work around the blank, you will have to change direction constantly, since working uphill or against the grain will almost guarantee that you end up splitting your work. Also, when you approach the grain at a steeper angle (i.e. as you come closer to working directly across the end grain), go with narrower cuts by using only half or a third of the width of your chisel in order to reduce resistance.

Refining - Spokeshave

Once you are near enough your final shape, further refine the perimeter with a sharp spokeshave set to a fine cut. Again, feel for the optimal cut continuously by skewing the spokeshave at different angles, changing the set and even clamping the seat in different positions. Try to achieve a smooth, continuous circumference before you move on to shape the top and bottom edges.