Kaimusailing

There were a couple messages about the scarf jig and cutting scarf bevels. The jig has to be made with its faces exactly perpendicular to the saw table. The blade has to be adjusted to be exactly perpendicular to the table as well as parallel to the angle guide slot. Some blades are slightly out of true and it is not a manufacturing defect, it is a compensation for when the blade heats up during cutting. If you get non-perpendicular angles on both sides of the blade, split the difference.
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Another source of errors is the distortion of the wood itself. If you are seeking perfection you will have to resaw and surface planks that aren't true. They can have twist or cupped faces. They can have faces that undulate due to warping when the planks age. Some may come right out of the saw mill distorted. If you are laminating planks into a beam, sometimes you can laminate together planks that have the same amount of twist or other distortion that is similar between the two planks. A plank can be used as a partial near the end of the beam. There will be less effect on the shape of the beam, however if a distorted plank is in the middle of the beam, then the whole beam will be twisted or curved. If the beam can be laminated before assembly into the boat, it can be trued before assembly by making it slightly oversize, enough to keep the low spots within spec. Excess can be planed off, but a dished area can result in a dished out area on the finished beam. Epoxy and fillers can compensate for lots of discrepancies and still manage to create strong glue joints.
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Perfection is desirable for cosmetic reasons, but hidden areas will be fine with joinery that is utilitarian, however some will find that objectionable and spend a lot of effort to make even those hidden areas perfect. When my grandfather made something that was less than perfect, he said it was “rustic”, on Kaimu it is “workboat finish”.
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Meanwhile on the Brit cat next door, the search for perfection continues. They are using a new paint called “Quantum”, which contains a higher percentage of solids than most other LP paints. It is repairable, which means it can be feather sanded and repainted on any future damage.
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The ordeal of preparing their boat for this paint has pushed the Brits to the edge, but finally they had the paint rep coming over with a spray painting rig, after they had tried to roll the paint and found the results to be not acceptable. The picture is of the underside of their catamaran and the results of a first coat of the glossy paint. Its shiny surface magnifies any surface imperfections, but their hundreds of hours of preparation paid off with a lustrous finish.