I've located have a source of Okoume plywood from a large supplier that has a range quality accreditations (not Lloyds though) but I'm struggling to find information on what they all mean.
Any ideas on whether this would be a suitable source for a sailing row cruiser build?
6mm 2500x1220 FSC FRA THEBAULT TEBOMARINE, LIGHTWEIGHT 2.00 0.018 35.00 board 70.00
MARINE okoume plywood, glue class 3 EN314, STRUCTURAL exterior
conditions EN636-3S if faces coated & edge sealed, E1, CE2+
EN13986, BS1088, Q cert, FSC Mix 70% INT-COC-002322
This wood seems pretty decent. It sounds like it is manufactured in France and has the British Standard 1088 certification, which is what we're looking for. Much of the good plywood comes from France, and they are less likely to falsely apply the BS1088 designation. Glue Class 3 EN314 is the highest classification for plywood bond quality under EN314, which is specifically for plywood used in environments with exposure to moisture. So it alls sounds pretty good.
Thanks for the info. In case others are reading this later this plywood is less than half the price I've been quoted elsewhere, from suppliers specialising boat building supplies. The supplier is a nationwide chain here in the UK so I did NOT immediately disregard it as too good to be true. So glad I checked on here. The supplier is https://www.lathamtimber.co.uk/products/panels/plywood/hardwood-plywood/african?utm_medium=organic&utm_source=google
@Colin Wood
Hi Colin,
Might be wise the check with the company on the amount of layers building up the 6mm. From experience I know there's a 3 layer version and a 5 layer. 3 layers would have a thicker middle layer and more flexibility than the 5 layer version which is stronger.
For bulkheads and seats you'd want more layers instead of less.
Hope it helps.
All the best,
Michiel
Just checked the data sheets available on the French manufacturers site and there are indeed only 3 plies for both thicknesses. Seems like a fundamental issue so I guess I'd better find a different source. Thanks for the advice Michiel.
@Colin Wood
It's not that using a 3 layer 6mm is wrong, I justed wanted to point out the difference :)
@Michiel Kommer This is the first time I've taken on a project like this so I'm not in a good position to judge the significance of the choices of material. If the norm is for five layers and having fewer layers means less stiffness then that sounds like something I need to avoid whilst I still can.
I'm already planning on changing the plans a little to accomodate a different sailing rig. Two equal sized sails with a third more sail area than the Open Bic sails (because I already have them). After advice from Colin I'll be keeping the daggerbaord case where it is. I'll then balance the boat by experimenting with the position of a supplementary leeboard and / or reefing the aft sail. I'll add some extra fibreglass cloth to strengthen the hull where the leeboard is going.
@Colin Wood
Hi Colin, sorry it took a bit to reply but it's been a bit hectic around me.
I really just wanted to point out the difference, there's no norm or anything, and both 3 or 5 layer will do the trick. If you decide on the 3 layer and find its to flexible you can always add a layer of glass... and if you're tight on your budget it might be the better choice. What works for you is something only experience will tell. And big part of the fun of projects like this is the knowledge what you would do things differently next time:)
On using similar sails and leeboards I can't help from experience because I still haven't been in the water, but I did move the daggerboard out of the cockpit and am going to use 2 optimist rigs.
