BS6566 Plywood suitable?
Robert
is Okoume BS1088 except the 3mm which is BS6566. The owner said that
3mm isn't made to BS1088 standard because the melamine glue would
leach through the face veneer. He said that this wood was as good as
BS1088. This is what the 3mm has stamped on it. "WISA COLLAGE 3-A
100 250*122*03 2268. The invoice shows BS6566 and I believe the glue
is Phenolic. Is this suitable for boatbuilding or should I take it
back.
Thanks
Robert
Glenn Ashmore
has a slightly thicker face veneer and above 6 mm has two more plys.
6566 is marine plywood and is perfectly good for boat building. In fact,
the latest word is that Lloyds is considering dropping the 1088
designation all together.
Robert wrote:
--
Glenn Ashmore
I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Nicholas Carey
and said:
> To my knowledge the only difference between 6566 and 1088 is
> that 1088 has a slightly thicker face veneer and above 6 mm
> has two more plys. 6566 is marine plywood and is perfectly
> good for boat building. In fact, the latest word is that
> Lloyds is considering dropping the 1088 designation all
> together.
Ahh...but Lloyd's has nothing to do with BS-1088. BSI is
considering dropping it because the plywood industry isn't
willing to pony up money for upgrading the standard. BS-1088/4079
were last updated 30 Nov 1966 -- some 35 years ago. (BS-1088 is
for marine plywood made of untreated tropical hardwoods, while
BS-4079 is for marine plywood made of tropical hardwoods treated
to be resistant to attack by fungi and marine borers. Something
to consider.)
BS-1088 is a British Standard, issued by BSI (http://www.bsi-
global.com) -- The British Standards Institute. BSI is an ISO
affiliate on a par with ANSI. In fact, many if not most BSI
standards are ANSI and ISO standards (and vice-versa. But plywood
isn't one of those.)
Lloyd's Register of Shipping (http://www.lr.org) is a marine
classification agency. And although they share the name, Lloyd's
Register is different than Lloyd's of London, the assurance
group. The only thing they have in common is that they both
started at Edward Lloyd's coffee house in London towards the turn
of the 18th century. Lloyd's Register plays a leading role in
formulating standards for marine construction and safety. Part of
that is certification: LR offers type-approval of different
classes of marine supplies and equipment for use in ships --
everything from plywood, to navigation lamps. In the case of
marine plywood, Lloyd's standards are not necessarily the same as
those of BSI.
What these two groups have in common is that if you are willing
to jump through their hoops and prove to them that you meet their
standards, you get licensed to use their logo and claim standards
compliance. And they will pull it if you stop meeting the
standards. They both do QA audits. This is what gives the BSI
kitemark its value. Ditto with "Lloyd's Type Approved". They
actually mean something.
And, FWIW, if you rummage around the LR site, there's a
searchable database that will list all the plywoods available
that have a current certificate of Lloyd's Type Approval. Useful
if you're shopping for plywood.
Hope this helps.
Nicholas Carey
Well, I just looked at the BSI web site and BS 6566 is
* Withdrawn. It is an official standard no more. It's been move
the the 'Historic Standards' category.
* A specification for ORDINARY and not MARINE plywood.
BS-6566 has been partially (parts 4, 7 and 8) superceded by
BS EN-636 -- which again is a Standard, not for marine plywood
but for ordinary plywoods (3 parts: interior use, exterior use
and high-humidity use.)
BS-1088 *is* an active Standard, and it is for marine plywood.
BSI will kitemark plywood as meeting BS-1088; they don't have a
scheme for kitemarking ordinary plywood -- I just checked their
website.
Does your plywood have
the BSI kitemark on it. It looks like this:
http://www.bsi-global.com//Kitemark/images/kitemark.gif
From BSI's guidelines for displaying the kitemark:
| The Kitemark shall always appear on the certified product
| with the appropriate standard number written in close
| proximity. eg:
|
| BS xxxx
| PAS xxxx
| ISO xxxx
|
| The Kitemark shall not be displayed on products which have not
| been the subject of certification under these conditions.
Since they don't kitemark stuff to BS-6566, if it has the
kitemark on it it's probably bogus.
Here's the blurb from the BSI web site on BS 6566
* BS 6566:Part 1:1985 (WITHDRAWN)
Plywood. Specification for construction of panels and
characteristics of plies including marking.
* BS 6566:Part 2:1985 (WITHDRAWN)
Plywood. Glossary of terms
* BS 6566:Part 3:1985 (WITHDRAWN)
Plywood. Specification for acceptance levels for
post-manufacture batch testing including sampling
* BS 6566:Part 4:1985 (WITHDRAWN)
Plywood. Specification for tolerances on the dimensions of
plywood panels
* BS 6566:Part 5:1985 (WITHDRAWN)
Plywood. Specification for moisture content
* BS 6566:Part 6:1985 (WITHDRAWN)
Plywood. Specification for limits of defects for the
classification of plywood by appearance
* BS 6566:Part 7:1985 (WITHDRAWN, SUPERCEDED)
Plywood. Specification for classification of resistance to
fungal decay and wood borer attack
* BS 6566:Part 8:1985 (WITHDRAWN)
Plywood. Specification for bond performance of veneer plywood
And here's the blurb for BS-1088:
* BS 1088 & 4079:1966 (CURRENT)
Specifications for plywood for marine craft
Comprising 1088: Marine plywood manufactured from selected
untreated tropical hardwoods. Species of timber, quality of
veneers, jointing, lay-up of plies, bonding, defects and
marking; gives illustrations of the various bond qualities of
plywood. 4079: Plywood made for marine use and treated against
attack by fungi or marine borers. Covers cases where the risk
of attack by fungi or marine borers is more severe than
untreated timbers will withstand; gives a range of appropriate
preservatives.
They are both available from BSI...for a price. But a good
university library should probably have them.
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