Is it possible to go lighter?
Good to see woodeneye's build come in at under 50kg with Paulownia framing.
https://www.woodworkforums.com/f169/b...ml#post1165139
Comments from Woodeneye:
Quote:
Originally Posted by
woodeneye
Is it possible to go lighter? I think so, but not by much. The hoop pine I used was reasonably dense, and a lighter timber could be found. Also, I think it would be possible to use Paulownia more extensively. For instance, the inwales and gunwales are timbers that run the whole length of the boat, so using Paulownia for these elements would likely have saved me another 2-3kg. I went with Hoop pine here for aesthetic reasons. Mick might comment on whether this would be stretching it a bit, but I don't feel that would be the case at all.
Until I coated with epoxy, I was a little worried that the Paulownia would be subject to denting and knocks. However, it's amazing how much toughness epoxy imparts to a softer wood like Paulownia, so I'm no longer concerned about that.
I've been thinking along similar lines - how far can I push the use of Paulownia to keep weight down? I'm adding a little weight with widening and boxing in the middle seat, much as Watermaat has done (where is he, did he disappear over the horizon on that big boat he bought when his GIS was nearly complete?), but I want to keep weight down as I'll likely be roofracking to the water (only 5 minutes away) for a while once the boat is complete.
Things I've done/am doing/considering doing beyond using Paulownia for framing and chinelogs:
Transom stiffener from Paulownia with 4mm gaboon ply on top - already done - maybe 400g lighter than a transom stiffner of 450 - 500kg/m^3 timber.
Bulkheads 3 and 4 and ones sealing off front of middle seat from 4mm gaboon ply - have already done bulkheads 3 and 4 this way.
Middle and rear seat tops from 4mm ply with a bit more light framing underneath - not sure on this one, need to figure if it's worth it. Leave front seat top 6mm as it's helping hold up the mast support structure.
Gunwales of Paulownia, but still with a thin hardwood (vic ash?) cap on the outside. Was thinking of capping the gunwale top with a thin strip of vic ash also so that no paulownia is showing on the top and sides of the gunwale, but could maybe keep it simpler if the Paulownia surface hardens up nicely with epoxy coating.
Inwale spacers of Paulownia.
Inwales of Paulownia? Was thinking again of a thin hardwood cap for wear/dent resistance but maybe leave it off?
Mast step of two 20mm layers of Paulownia but with a layer of 6mm ply on top to maintain cross grain strength.
Mast partner of 20mm thick Paulownia but with 6mm ply on the bottom surface for cross grain strength. Possibly a sandwich of (from the bottom) 6mm ply, 20mm paulownia then the 6mm ply of the seat top.
Looking forward to some feedback!
Ian