Three more hours today. While Cinzia was fighting with the sander, I drilled the oversized bolt holes which will be coated with thickened resin.
I have some reservations towards those akas. First one is that those planks have several knots, a few of those being quite large. Are those knots going to be a problem, structurally speaking?
Second: they are heavy. I haven't measured the weight but based on sizes and specific weight of the fir, we should be close to 100 kg! I'm wondering if one could design a lighter system: nothing complicated, like a box section made of plywood and lumber. I sent an email to John Marples, we'll see what he replies.
Total work time to date: 539 hours.