A New Mould for the Front Decks
I realised the front decks needed a changing curvature, not the standard radius from the plans. After rebuilding the mould, the 9mm plywood seems to be bending just fine.
Well, I messed up. Last year.
After making sandwich decks for main cabin in rush (it was bloody cold and I needed place to sleep 😂) I switched to making cabin roofs. Thinking “I’ll make decks over front cabins later”.
Well, job loves idiots.
The cabin roof has different radius of the curvature than decks. Which means I had to change the mould, only to change it again now because decks again have different radius (yeah, same like the decks over main cabin, you follow it well…).
Bittersweet part of this is I would probably had to change moulds anyway. The plans call for using same deck curvature radius in both cases, which is logical since they start on the same bulkhead. But the curvature gets more and more pronounced when you get to the bows and by half-bulkhead in the middle would still work but on the bulkhead 1 in the bows it would need a really hard persuasion mechanisms 😂 as the gap at this standard curvature radius would be something around an inch by the edge of the hull. Theoretically possible with good persuasion and additional elements increasing the surface area of the epoxy seam but it would place unnecessary high load in the construction in a place I really do not want to have one…
After discussing this problem with Hanneke we both agreed that this size gap should not be forced and that I should make a mould which would change profile. I had some reservations about this earlier but decided to try - and later realised that since in the every point the batten run along the deck touches all three bulkheads it was not any of my error and the surface is indeed a surface of the cone - which means plywood should be bending only in one direction, without problems and extra pressure so it should indeed work.
Few hours later after dismantling one mould, reusing one of its crossbeams (cabin roof has exactly the radius of its curvature like the 2/3 half bulkhead, who knew?) and routing slots for the 2x3 timbers holding that together I tried 9mm pieces of plywood which form the mould - it seems to work fine. Tomorrow morning I will fit extra metal reinforcements on the beams/crossbeams so the timbers do not move under the pressure of the bent plywood (guess where and how I learnt this one!) and screw in the 9mm plywood pieces - and hopefully tomorrow afternoon the first part of the deck will be already made.
#tiki38 #buildingwharram #theseanation
