The time came to cut the rebates in the mast sides.
As usual the build manual assumes that we have a table saw, which of course I do not.
Actually I recently met a woodworker who does have a table saw and offered me its use, but it is really not feasible to transport sixteen foot long pieces thirty miles to his workshop.
So I invoked my original plan, which was to use a circular saw.
The saw blade can be adjusted to cut the required depth, but the saw itself needs a wide and flat surface to run along when cutting. This is a problem when cutting the edges of the side pieces.
I solved this by clamping a long piece of 2" wide stock between the two side pieces to provide a flat surface for the saw to run along. You can see how that works in this pic.
The piece of stock is moved and clamped along the sides until the cut is complete, and then the same thing is done to complete the cut on the other side piece in the opposite direction.
They are then turned over and the process is repeated.
This is the saw.
I bought it specifically for this purpose, and was worried that it might be overkill for the job. But it turned out to be just right - it requires a powerful saw to cut these rebates.
Here is the edge rebate cut in one side.
And here is the second cut in the other side.
The cuts in the faces followed. They were much easier to make. Here is the first cut.
It is an excellent saw and made a sharp and accurate cut, as can be seen here.
Here we see a finished side piece.
And here is a partly cut rebate in close up.