Wednesday, 21 February 2018

Building the Mast - Chapter Two - Planing and Bevelling

This is a brief report on four days in the workshop. There's a lot of work involved in planing down a spar, but it doesn't take long to write about it.

The two halves were trued up on the thickness planer, then a slight hollow put in the middle to ensure that the outside edges would be a very tight fit when glued. It's thinner than the photo suggests!

Having scooped out the hollow section, which I decided to expand to eleven feet while doing it, the next step was to saturate it with clear epoxy, in the hope that this will avoid rot developing in what could be a nice warm incubation chamber later. I contemplated a layer of woven roving as well, but decided that that would be a step too far. Time will tell.

This enabled the sections to be put together, using all available clamps.

Then we discussed cutting the bevels on the table saw, using a tapered infill for the top section, but soon discovered that this could be at the expense of a nice new blade and stopped. A bigger machine would have coped, but it would still be a risky operation.

There followed a few days of planing, first power planer, then hand planes. For the tapered section at the top a good trick for measuring off is to place a twelve inch ruler diagonally across the workpiece and run it along marking off the 3 1/2 inch and 8 1/2 inch positions. But basically this is just careful, hard work until it's as close to the lines.

The bottom section was redesigned during the operation, as the transition from square to round can be easily done without a intervening octagonal section.

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The Wherrymen

The Wherrymen
Two old friends on the water