Power ply

[pipefitter]

Has anyone used this stuff before?

http://www.worldpanel.com/Powerply.html

[Pericles]

The spec looks promising. However, BS 1088 went through a period of indecision a few years ago.

British Standard BS1088:1966 is currently under review (http://www.marineply.com/bs1088.htm) and may ultimately be replaced by a "guarantee" policy. However as a manufacturing standard it will continue to be used for the foreseeable future.

BS 1088 specification is a marine plywood (http://en.wikipedia.org/wiki/Marine_plywood) specification that applies to plywood produced with untreated tropical hardwood veneers that have a set level of resistance to fungal attack. The plies are bonded with WBP glue. Although the initials BS are for "British Standard", the finished product does not have to be "British made". The standard is associated with Lloyd's of London (http://en.wikipedia.org/wiki/Lloyd%27s_Register) since it performs testing of products to this standard. WBP Glue Line -- BS 1088 plywood must use an adhesive proven to be very resistant to weather, micro-organisms, cold and boiling water, and steam and dry heat. The product's bonding must pass a series of British Standard tests.
Face Veneers -- These must present a solid surface that is free from open defects. Face veneers must be free of knots other than "sound pin" knots, and there can be no more than an average of two such knots per square foot over the entire surface of the plywood sheet. The veneers must be reasonably free from irregular grain. The use of edge joints is limited, and end joints are not allowed.
Core Veneers -- Core veneers have the same basic requirements as face veneers, except that small splits are allowed, and there is no limit on the number of pin knots or edge joints. However, end joints are not permitted.
Limits of Manufacturing Defects -- Defective bonds, pleats and overlaps, and gaps in faces are not permitted. Occasional gaps may be repaired using veneer inserts bonded with the proper adhesive.
Moisture Content -- BS 1088 plywood must have a moisture content between 6% and 14% when it leaves the factory.
Finishing -- Boards will be sanded on both sides equally.
Length & Width -- The length or width of a board produced as a standard size shall not be less than the specified size nor more than 6.3 mm (0.25") greater than the specified size.
Squareness -- The lengths of the diagonals of a board shall not differ by more than 0.25% of the length of the diagonal.
Thickness Tolerances -- Tolerances vary as follows.
4 mm +.02/-0.6 6 mm +.04/-0.65 9 mm +.06/-0.75 12 mm +.09/-0.82
15 mm +.1/-0.9 18 mm +.12/-0.98 22 mm +.16/-1.08 25 mm +1.8/-1.16From the above we can assume that 6 mm material will arrive at thickness' between 6.04 mm and 5.35 mm.
Face Veneer thickness -- For any three-ply construction, which applies to 3 and 4 mm material, each face veneer shall be not thinner than 1/8 of the total thickness of veneers assembled dry. Since the dry thicknesses of the boards are 3.6 and 4.6 respectively, we can assume that for these thicknesses only the face veneers will be as follows:
3.6 mm dry x 12.5% (1/8) = 0.45 mm 4.6 mm dry x 12.5% (1/8) = 0.575 mmMulti-Ply Construction-- This applies to boards thicker than 4.8 mm (3/16")
Each face veneer shall be a minimum of 1.3 mm and not thicker than 3.8 mm.
Each core veneer shall be no thicker than 4.8 mm
The new standard is below.

http://standards.mackido.com/bs/bs-standards24_view_127.html
http://standards.mackido.com/bs/bs-standards24_view_128.html

I'd give Powerply a try.

Pericles

[Tom Lathrop]

A 73% weight penalty over occume ply. 33 lbs vs 19 lbs. Way to heavy for most boats. Certainly too heavy for any boat I would ever build.:(

[Nicholas Carey]

The spec looks promising. However, BS 1088 went through a period of indecision a few years ago.British Standard BS1088:1966 is currently under review and may ultimately be replaced by a "guarantee" policy. However as a manufacturing standard it will continue to be used for the foreseeable future.This uncertainty regarding BS-1088 is no longer applicable: the standard BS-1088 was revised/renewed in 2003:
BS 1088-1:2003 Marine plywood. Requirements (http://www.bsi-global.com/en/Shop/Publication-Detail/?pid=000000000030062733)This part of BS 1088 specifies requirements for marine plywood for use in the manufacture of marine craft and in other marine and waterway applications. It also applies to marine plywood that has been selected for use in building construction, in extreme climates and in such applications as vehicle bodies and general building work where a high standard of durability is required or where the cost of replacement in the event of failure might be high.

This standard does not include strength data, which can be used to derive characteristic values or grade stresses for use in engineering design.

Together with BS 1088-2, it supersedes BS 1088:1966 and BS 4079:1966, which are withdrawn.
BS 1088-2:2003 Marine plywood. Determination of bonding quality using the knife test (http://www.bsi-global.com/en/Shop/Publication-Detail/?pid=000000000030062735)This standard describes a method of assessing the bonding quality of marine plywood using two groups of test specimens, one of which has been immersed in cold water and the other of which has been immersed in boiling water or subjected to steam. It is intended for use as a manufacturing quality control test and not for demonstrating verification of conformity to a plywood specification.BS 1088 specification is a marine plywood (http://en.wikipedia.org/wiki/Marine_plywood) specification that applies to plywood produced with untreated tropical hardwood veneers that have a set level of resistance to fungal attack. The plies are bonded with WBP glue. Although the initials BS are for "British Standard", the finished product does not have to be "British made".

The standard [BS-1088] is associated with Lloyd's of London (http://en.wikipedia.org/wiki/Lloyd%27s_Register) since it performs testing of products to this standard.Lloyds Register Type Approval (http://www.lr.org/Industries/Marine/Services/Certification/Type+approval.htm) is a different wee beasty than BSI certification. You can search for type-approved marine plywood manufacturers here: http://www.cdlive.lr.org/information/default.asp?preOpen=Approvals

However, the user interface not very intuitive and it wants Internet Explorer (it gets all unhappy about Firefox). Go down to Approvals..Approved Products List..Product Index. Just through the hoops and scan the right side for "Plywood and Other Wood Boats (Part 1A)". Click on that and you'll see the list. No US manufacturers currently hold LR Type Approval certificates for marine plywood: Shelman, Joubert, Burguet are the big ones. All LR Type Approved plywood manufacterers are all located in Europe save two: one (Samling) in Malasia, and the other (CEMA Bois de l'Atlas) in Morocco.

BS-1088, however, is enforced/certified by the British Standards Institute (http://www.bsi-global.com/en/ProductServices/) (an ISO affiliate, although this particular standard is non-ISO/ANSI/DIN). Anybody can be certified by BSI (BSI has offices 'round the world (http://www.bsi-global.com/en/Country-Selector/). Here's the US/Americas office. (http://www.bsiamericas.com/) BS-1088 certified plywood will carry the trademark BSI "kitemark":

http://www.bsi-global.com/upload/Product%20Services/Shop%20images/merchandise%20page/poster%20200.jpg

Part of the conditions for bearing the kitemark are that BSI tests the product to verify that it actually meets the specification(s) for which it is certified and that BSI be able to periodically and randomly inspect the premises to validate that the processes haven't changed and that the standard is still being met. BSI also takes periodic random product samples for testing.

More at
http://www.bsi-global.com/en/ProductServices/About-Kitemark/
https://services.bsi-global.com/Kitemark/Click here for the actual conditions of contract (http://www.bsi-global.com/en/ProductServices/About-Kitemark/Conditions-of-Contract/) for kitemark certification, click here.

Like LR, BSI also has a directory of Kitemark-certified manufacuturers/products, but I have not yet managed to find marine plywood in it (It's user interface is also clumsy).

[Nicholas Carey]

You'll notice on this page:

http://www.worldpanel.com/marineplywood.htm

That World Panel makes no claims that PowerPly is either BS-1088 certified or holds a LR Type Approval certificate -- they just called it exterior plywood.

The manufacturer of the panels in India -- http://www.austinpowerply.com/austin/marinepowerply.htm -- likewise makes no pretenses that the stuff is BS-1088 certified.

[seanz]

Austin Power ply?
Who thought that one up?
It also says on the website that the logs are sourced from Myanmar (aka Burma) ,doesn't the U.S. have trade sanctions against them?

[kc8pql]

Interesting. I just noticed the forum's newest member is "worldpanel".

[seanz]

Well that didn't take long.
And a hearty WBF welcome to our newest member.

[pipefitter]

I didn't see that as the newest member.
I doubt it has anything to do with my inquiry. I was actually looking for Meranti. I came across power ply in my search. I found out that meranti is going to be harder to get so I looked at alternatives.

Okoume has been said to be bs1088 but I don't see how, being it is a non durable species of wood. I found meranti to be a good value being of the same rating or having passed independent rating tests but with a moderately durable wood species.

I don't see a need for poisonous wood on dry sailed boats but it seems it could have a place to the contrary. I wonder if being it is a tougher,heavier and more durable wood,if there could be some scantling adjustments or if it would be a good bet for a stitch and glue conversion from a traditional design where included ballast might be a concern. Surely there is a situation where modern panels could be too light?

It might be a good alternative for boats that live in these Florida waters from the waterline down and utilize the Okoume for topsides to cancel out the added weight.

When I talked to the rep a few years ago,I was under the impression that the plywood was manufactured to bs1088 standards but I didn't take it in complete sense of the designation. At any rate,the meranti that I got has held up to some extreme environmental exposure and the bugs didn't want much to do with it. Can't say the same for the "marine" exterior fir ply though. It was pretty much destroyed in less than half of the time.

[Pericles]

Nicholas Carey,

Thank you for the detailed information, especially that World Panel does not claim BS 1088 for Powerply. Makes me wonder if the link http://www.worldpanel.com/Powerply.html Pipefitter posted is an old one.:)

Regards,

Pericles

Powerply, the new standard for Marine Plywood
4 x 8 sheet size
BS1088
Rot-Resistant (see below)
Straight, stable, and (in our opinion) built like a tank

[Pericles]

Pipefitter,

Here is a description of BS 1088 requirements from MarinePly in the UK. http://www.marineply.com/technical.htm It's really about absence of defects. You will see that being durable is not a requirement, but encapsulating the Okume in epoxy and glass results in a tough vessel, IMO stronger than fir marine ply. Your idea for a Meranti hull and Okume topsides sounds perfect for Florida. In the UK, our Summer is like your Winter. Its rained every day here for a week.:mad:

Pericles

The standard applies to plywood made from untreated tropical hardwood veneers having a suitable level of resistance to fungal attack, with a bond of WBP glue quality between the plies.
Bonding
Phenolic formaldehyde WBP to BS EN 314-2 class 3.Stag marine plywood can be obtained Lloyds Type Approved to British Standard BS6566 part 8 (now withdrawn and superceded by BS EN 315)
Species
Faces and cores are produced from Okoume/Gaboon (Aucoume klaineana), which is classed as non-durable.
Veneers may be rotary or sliced cut. The method of cutting is at the option of the manufacturer unless otherwise specified.
Face veneers shall present a solid surface, free from open defects. They shall be free from knots, other than pin knots, of which there shall be no more than 6 in any area 30 cm square, and not more than an average of 2 per 30 cm square.
Veneers showing compression failure shall be excluded. Occasional discoloration is permissible.
Tolerances
Thickness tolerance - 4mm +.02/-0.6, 6mm +.04/-0.65, 9mm +.06/-0.75, 12mm +.09/-0.82
15mm +.1/-0.9, 18mm +.12/-0.98, 25mm +1.8/-1.16.
Multiply Construction applies to boards thicker than 4.8mm - each face veneer shall be a minimum of 1.3mm and not thicker than 3.8mm with a core not exceeding 4.8mm.
Quality
Boards will be sanded on both sides evenly, face veneer thickness shall not be less than 1/8" of the total thickness of veneers. Moisture content at the time of leaving the factory shall be between 6 and 14%.
Conclusion
Stag marine products meet the highest specifications available, the above details are only a precise of the rigourous applied to meet BS1088 and subsequent BS EN standards. A full transcript of the standards is available from good stationers.

[Bill Lowe]

I called worldpanel yesterday and they are sending a sample. This product could be very useful on larger projects. I have a 50' Shephard and a 36' Grand Banks in the yard needing cabin sides and decks. The Shephard also is getting some of the upper hull sheathing replaced. We have used Coosa board for decks but its very expensive and not wood.

[erster]

World Panel??? Super service and friendly folks, :cool:But the more I see and learn, the more I am beginning to believe that Okume from anyone is highly overrated and only for dainty garage boats brought out for a few hours on the weekend, unless glued together, covered and protected with gobs of glass.;) The only advantage versus any other species seems to be weight.

[Cuyahoga Chuck]

Okuome has been chosen for practical reasons that go beyond weight.
The industry needs a consistant supply of a tropical hardwood that verneers nicely. Okoume does that and it is plantation grown so there is no need to rely on the vagueries of forest grown sources. The fact that it is significantly lighter than it's competitors can't hurt either.

[erster]

Okuome has been chosen for practical reasons that go beyond weight.
The industry needs a consistant supply of a tropical hardwood that verneers nicely. Okoume does that and it is plantation grown so there is no need to rely on the vagueries of forest grown sources. The fact that it is significantly lighter than it's competitors can't hurt either.

I see little advantage to buying expensive plywoods, and the labor involved in building the hull knowing what we all know dealing with some deteriations of the layer on the surfaces if not coated with an additional product or in composite building. These known facts are well supported throughout the industry. Also lighter is not always better when comparing scantlings either. Like everything else, its not a cureall or fixall by any means and comes with some drawbacks in the wrong enviroment and in the wrong hands of illusion. It takes nothing to ding the stuff either, standing on its on. Thats my contention and I am sticking to it. Your opinion may vary.:) Later

[Honda_Shadow]

Erster:
WOO HOO! That means I can build with Oriented Strand Board!!! ;)

[pipefitter]

World Panel??? Super service and friendly folks, :cool:But the more I see and learn, the more I am beginning to believe that Okume from anyone is highly overrated and only for dainty garage boats brought out for a few hours on the weekend, unless glued together, covered and protected with gobs of glass.;) The only advantage versus any other species seems to be weight.

Thats what I was told as well,Erster. And that by the time that all the added protection considerations and such,that it is actually better economy to use the Sapele below waterline on boats that see frequent use with an active bilge and with customers that rarely maintain the boat as outlined by the builder if rotting is to be a concern.

Light weight seems to be more a concern on modern design composite constructions where someone has to carry a boat over their head more than on a 20ft power boat on a trailer. A 20ft power boat made of plywood is still going to be substantially lighter than it's fiberglass alternative.

I think for my own boat I could use about anything because it doesn't get wet long enough and rarely any on the interior or bilge. I could make good luan last I think with glass coating.

[erster]

Erster:
WOO HOO! That means I can build with Oriented Strand Board!!! ;)
You can build with anything, just like I build with Okume. Whatever flaots your boat as I have also built with some stupid things, too. ;):D But I also understand some of its drawbacks. Even without glassing the stuff, when painting the first thing I do is to either use the two part epoxy primers or in some cases I will coat the wood originally with the Interprotect system which hardens the faces of it for just painted surfaces. Oh well, time to go test some of the stuff under stress conditions on the water. I sure hope it holds up. Please say a pray from me. ;)

[pipefitter]

Power ply might be a good alternative for boats with sealed bilges,self bailing decks and flotation foam.

[Tom Lathrop]

The heavier plywoods would probably fine on displacement boats, especially those that are not to be trailered. In one of my boats, Power Ply would add over 700 lbs to the weight. That is 5 adult passengers that can not be put ashore. The penalty on performance, fuel cost and trailering weight is not to be taken lightly (pun intended) in a planing power boat or a sailboat that aspires to more than middling hull speed.

[pipefitter]

The heavier plywoods would probably fine on displacement boats, especially those that are not to be trailered. In one of my boats, Power Ply would add over 700 lbs to the weight. That is 5 adult passengers that can not be put ashore. The penalty on performance, fuel cost and trailering weight is not to be taken lightly (pun intended) in a planing power boat or a sailboat that aspires to more than middling hull speed.

I see your point,Tom. A boat comparable to my own in fiberglass weighs twice as much. I admit that I didn't look at the weight differences .But since you mentioned it, I was thinking that is some boat plans that say it is ok to use DF ply in the entire build,it could be considered to use the heavy durable stuff on the wet side and compensate with the lighter okoume on the dry. If it was worth it's salts,there might be instances where it could be considered.

I couldn't find all the information for all the plywoods on that site as a comparison and haven't bothered to look elsewhere yet. I do know that Okoume is very light. I think Okoume is a good bet where one wants to add all the comforts and parts of a larger boat into a smaller one which seems common these days.

[pipefitter]

Nicholas Carey,

Thank you for the detailed information, especially that World Panel does not claim BS 1088 for Powerply. Makes me wonder if the link http://www.worldpanel.com/Powerply.html Pipefitter posted is an old one.:)

Regards,

Pericles

Powerply, the new standard for Marine Plywood
4 x 8 sheet size
BS1088
Rot-Resistant (see below)
Straight, stable, and (in our opinion) built like a tank






It wasn't on that site a few months ago,Pericles. I think it is new or new to them. I was really checking on how fuel prices and such as effected boat building supplies or if I should stock up. :)

Some of the metals I use in my trade have increased 80%.

[Tom Lathrop]

I see your point,Tom. A boat comparable to my own in fiberglass weighs twice as much. I admit that I didn't look at the weight differences .But since you mentioned it, I was thinking that is some boat plans that say it is ok to use DF ply in the entire build,it could be considered to use the heavy durable stuff on the wet side and compensate with the lighter okoume on the dry. If it was worth it's salts,there might be instances where it could be considered.


Pipe, I did not mean that there is no place on boats for the heavier and more durable plywoods. Meranti and Kerung (sp) come to mind. The finer ones like Sapele are great but more costly as well as heavier. I know that Occume is not durable but have experience with its use in exterior hulls on boats for many years, some bad and some good. The good experience is always where it is well protected by a epoxy/fabric sheath. The bad is where it was not well protected. No blanket statement is ever correct in these issues.

Boats that I design and/or build are always driven to occume for the lighter weight. I accept the durability issue and build with that in mind. I have used some meranti but not a lot.

[pipefitter]

I didn't think that's what you meant,Tom. I thought your reply fair and with good thought. This stuff might be great for dagger boards and rudders and such from a stability/durability standpoint.
My main concern would be the hazards of handling and milling the stuff. Some PT products for instance are obnoxious to work with.

I have meranti that has been outside for 6 years now with no coatings on it. I really didn't expect it to hold up as well as it has. I hadn't even thought about testing it but found it under the leaves and such when cleaning up the back yard. World panel rep stressed to me when I bought it that it was meant to be sealed just as an aside to the order conversation. They really are great folks to deal with. With that in mind,I am inclined to take their ratings and comments as pretty close to what they classify it as,even if the standard is of their own opinion.