I've found a good deal locally on Okoume Plywood. It is a national Plywood and Door company. I'm assured over the phone that it is Exterior Marine Okoume. How can I tell when I pick it up, having never seen Okoume before. Will each individual piece be marked? What should I look for?
Thanks for your help
Okoume Plwod--How to be sure????
If it is Lloyd's certified it will have a BS1088 stamp and a Lloyd's stamp. It is possible to have plywood marked with either grade without a Lloyd's stamp.
Check for knots (BS1088 will very few tiny ones, or none) and that the plies are all the same thickness. Six mm will have five equal-thickness plies. There will be no voids visible along the edge of the sheet. Since most marine Okoume is made outside the US, the sheet will probably be a little bigger than 4 feet by 8 feet.
The manufacturers of Okoume rate their panels and apply the stamp. There are standards for this, but they are not applied by an impartial third party. Caveat emptor. If you don't recognize the brand (such as Shelmarine) you should inspect the panels closely. Frankly, Okoume is not particularly rot resistant, but is available in light-weight, knot-free, void-free panels with good adhesives and so has become the "gold standard" for boat-building plywood. If there were such a thing as Douglas fir marine plywood that was void-free, knot-free, and football-patch-free, I would use that instead of Okoume.
I have read on the web that 6566 is an outdated grading mark, and has been replaced by standards such as BS EN 636-1, BS EN 636-2, BS EN 636-3 and DD ENV 1099. I have not seen these grades in use in the USA.
Good luck.
- Rick
Check for knots (BS1088 will very few tiny ones, or none) and that the plies are all the same thickness. Six mm will have five equal-thickness plies. There will be no voids visible along the edge of the sheet. Since most marine Okoume is made outside the US, the sheet will probably be a little bigger than 4 feet by 8 feet.
The manufacturers of Okoume rate their panels and apply the stamp. There are standards for this, but they are not applied by an impartial third party. Caveat emptor. If you don't recognize the brand (such as Shelmarine) you should inspect the panels closely. Frankly, Okoume is not particularly rot resistant, but is available in light-weight, knot-free, void-free panels with good adhesives and so has become the "gold standard" for boat-building plywood. If there were such a thing as Douglas fir marine plywood that was void-free, knot-free, and football-patch-free, I would use that instead of Okoume.
I have read on the web that 6566 is an outdated grading mark, and has been replaced by standards such as BS EN 636-1, BS EN 636-2, BS EN 636-3 and DD ENV 1099. I have not seen these grades in use in the USA.
Good luck.
- Rick
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agiannelia
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I'd look at it closely to see if it matches the description that others gave. Critical to the mission are the following characteristics:
No surface knots,
No internal voids
5 plies over 6 mm, not 3.
Waterproof/Boilproof glue.
If is really cheap and they say it is marine, buy a sample, cut it up and boil it. It passes, use it, and let us know where you got it, if not, get your money back.
No surface knots,
No internal voids
5 plies over 6 mm, not 3.
Waterproof/Boilproof glue.
If is really cheap and they say it is marine, buy a sample, cut it up and boil it. It passes, use it, and let us know where you got it, if not, get your money back.
Alex_G
Steven,
Trying to identify wood types visually has got to be a game for experts. Wood scientists use microsopes and still get fooled.
Because I'm a tenderfoot in boatbuilding I feel it's better to pay the going price to someone with a known reputation and avoid dealing with unknowns who are offering "deals". It doesn't take a genious to come up with a rubber stamp that says BS1088.
Saying something "meets BS 1088 specifications" is not the same as saying the product is actually registered with the British Standards bureau or with LLoyds.
As far as I know, none of the top grades of okuome/meranti ply are made in the US. The folks who make this stuff are few in number and have names that are well known in the boatbuilding world. If your in doubt ask for the manufacturer's name. It shouldn't be hard to find out if it's someone with a reputation or a pretender
Charlie.
Trying to identify wood types visually has got to be a game for experts. Wood scientists use microsopes and still get fooled.
Because I'm a tenderfoot in boatbuilding I feel it's better to pay the going price to someone with a known reputation and avoid dealing with unknowns who are offering "deals". It doesn't take a genious to come up with a rubber stamp that says BS1088.
Saying something "meets BS 1088 specifications" is not the same as saying the product is actually registered with the British Standards bureau or with LLoyds.
As far as I know, none of the top grades of okuome/meranti ply are made in the US. The folks who make this stuff are few in number and have names that are well known in the boatbuilding world. If your in doubt ask for the manufacturer's name. It shouldn't be hard to find out if it's someone with a reputation or a pretender
Charlie.
The answers are at our web site:
http://plywood.e-boat.net/index.php
On the 1st page, we explain the advantages of marine plywood.
Then, go to the help pages to read more:
http://plywood.e-boat.net/plyhelp.php
There, we list the wood species used and give almost the full text of the BS1088 specification.
From that same page, there are links to the US specifications and to a page commenting on the use of marine plywood.
Bottom line: BS1088 PLUS the Lloyds approval is the best you can get.
http://plywood.e-boat.net/index.php
On the 1st page, we explain the advantages of marine plywood.
Then, go to the help pages to read more:
http://plywood.e-boat.net/plyhelp.php
There, we list the wood species used and give almost the full text of the BS1088 specification.
From that same page, there are links to the US specifications and to a page commenting on the use of marine plywood.
Bottom line: BS1088 PLUS the Lloyds approval is the best you can get.
Jacques Mertens - Designer
http://boatbuildercentral.com
http://boatbuildercentral.com
A friend just bought some 6mm plywood that was stamped "Okume plywood manufactured to BS1088 standards -- made in France". The sheet consisted of three thick inner layers with faces that were much thinner and the wrong color for okoume. There were no Lloyd's stamps.
My friend has already cut the sheets an turned them into boat parts (the coamings, rear bulkhead, and side decks for a San Francisco Pelican) so I'm not going to say anything to him. His hull is made from 3/8" marine fir plywood and solid wood parts from CVG Douglas fir that is plenty strong. I'm pretty sure he was taken on the "BS1088" he bought.
Buyers beware...
My friend has already cut the sheets an turned them into boat parts (the coamings, rear bulkhead, and side decks for a San Francisco Pelican) so I'm not going to say anything to him. His hull is made from 3/8" marine fir plywood and solid wood parts from CVG Douglas fir that is plenty strong. I'm pretty sure he was taken on the "BS1088" he bought.
Buyers beware...
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Troutlet
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lookout
Rick how did your friend wind up with the faux BS plywood? It might help someone else not to get taken if we knew who the bad guy was.
When I say BS I mean British Standard and not Bull S_ _ _ although either word would propbably apply here right?
When I say BS I mean British Standard and not Bull S_ _ _ although either word would propbably apply here right?Who is online
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