It wasn’t easy to mark the waterline. What I wanted to do was place the boat on its sole and go round the boat marking the hull, at the correct height with a pencil, fixed in a block of wood. But I needed a totally flat surface for this and I don’t have one of those. So, knowing or hoping or imagining that the bow and stern will just kiss the water, I started by looking at the boat from a distance while holding a metal ruler horizontally at arms length. Trying to keep the boat and the ruler in focus at the same time was taxing but it gave me an idea of where the line was supposed to go. Then I laid a long, straight edge across the highest (actually the lowest but as the hull’s upside down, the highest) part of the bottom and measured the vertical distance between the straight edge and the bows and the straight edge and the stern. Then I went round the boat measuring this height at short intervals and leaving pencil marks. I laid a length of string around the hull coinciding with the marks and retreated with my ruler to a fair distance. Again holding the ruler up, I could judge if the string was in the right position. It naturally hung in a curve that didn’t match the pencil marks so I fixed it in place using small pieces of masking tape. Then retreated again, checked and adjusted the line and finally marked it with tape.
I suppose that marking this line and painting the bottom red is a bit of a nonsense really. It’s not going to make the boat sail any better, there’s no way of knowing that it’s actually in the right place until the hull hits the water and it makes for a slower and trickier paint job.
It looks good though, a tad serious for a boat this size, but good.