Pro's and Con's of using Luan Wood

[109jb]

Re: Pro's and Con's of using Luan Wood

The section of floor in my 16' 1988 Sea Ray Seville that I replaced to finish this boating season appeared to be CDX as it had visible unfilled knots in the face ply that faced down. The "C" grade side was facing up.

 

[Mark42]

Re: Pro's and Con's of using Luan Wood

I just spent some time reading various "Industry Srandards" publications by various organizations that list what they think the industry standards should be. Organizations like the NMMA, The American Boat and Yach Council (ABYC), The Boat Owners Association of the US (BoatUS), British Marine Industries Federation(BMIF), the International Marine Institute (IMI), and the Marine Fabricators Association (MFA).
All list the standards to meet their respective certifications. I read about boats under 26 feet. They list dozens of pages of approved Bilge Pumps, Vent hoses, Steering Cables, Control Cables, Blower motors, and on and on. But not once did any of them specify the grade or even the materials used to construct the hull. Not once. You could build your hull from paper mache coated in candle wax and they don't care. As long as you have one of the hundreds of comercially available bilge pumps in it.

I am not saying that some where, some group does say that a certian quality of plywood should be used in the floor and transom. But if it does exist, I just could not find it.

99% of the certifications require that all the hardware and systems (like I mentioned above) meet their list of acceptable manufacturers and model numbers. Also, the proper placement of navagation lights, and they test for level flotation. But the hull, stringers, deck and transom can be made from low budget products and that will not impact the certification one bit.

....is a substrate available en mass which is not up to the standards recommended in the marine industry.
...

More to the point: Exactly who's industry standard are you referring to, and exactly what documentation have they published that supports your claim for an "industry recommended" product. Having this information would go a long way towards resolving the issues in this debate.

If someone can prove me wrong, I sure would appreciate it, because it would mean that "industry standards" migh actually mean something in boats under 26 feet. But if you read fishrdan and 109jb posts above, you will find that their boats were built with OEM wood products that apparently don't meet your "industry standards" reccomendation for wood products.

I personally do not follow "industry standards" with my boats. Probably because I did not find any that relate to construction of a hull. I follow the US Coast Guard regulations for small craft, even though they only reccomend that home builders follow the same rules as manufacturers. So I do. My boats, built with my choice of wood, foam and glass materials will pass any Coast Guard inspection at any time. Be it fuel system, electrical, or mechanical and that is the bottom line.

 

[Lou C]

Re: Pro's and Con's of using Luan Wood

When I did the deck in my 88 FW Horizion I used ACX from the local lumber yard and I coated all pieces with two coats of rot doc's (Smiths) CPES. I used mahagony for the gas tank stringers/supports and coated that also. So far so good. The main thing even tho people obsess about what to use, is the storage of the boat. Keep moisture out of it and let air circulate. And whatever you do, do NOT put carpet on the deck, that is the absolute worst thing in an open boat, it holds moisture and can be wet underneath for months. I also sealed all penetrations with 3M 4200. I had my deck 'glassed in by a local shop and they used a non skid vinylester gelcoat on it. Came out nice and stays dry!

 

[i386]

Re: Pro's and Con's of using Luan Wood

The main thing even tho people obsess about what to use, is the storage of the boat. Keep moisture out of it and let air circulate. And whatever you do, do NOT put carpet on the deck, that is the absolute worst thing in an open boat, it holds moisture and can be wet underneath for months. I also sealed all penetrations with 3M 4200. I had my deck 'glassed in by a local shop and they used a non skid vinylester gelcoat on it. Came out nice and stays dry!

^^^ Yes!

Proper Storage.

Proper bedding of screws and thru-hull fitttings.

Carpet.

Failure to make hull repairs ASAP when minor damage occurs.


IMO, the aforementioned items are the cause of 95% or greater of rotten decks, stringers, and transoms. Also IMO, proper storage and ventilation may even negate the effects of having carpet on most boats.

 

[seven up]

Re: Pro's and Con's of using Luan Wood

hey 77 Mutiny,


The excuse that pressure treated is used by boat manufacturers is a weak argument.

The pressure treated plywood used by boat manufacturers is KDAT: kiln dried after treatment. Also, this plywood requires minimum retention percentages of at least .40 for contact with fresh water and higher retentions for salt water contact.

The pressure treated plywood available at box store chains is no where near these certifications. From neighborhood to neighborhood the quality of the box store stuff goes from bad to worse. The inner plys are weak and rampant with unfilled gaps and voids. Just look at the edge of the panel.

Every sheet of luan I have used was manufactured for interior use. Great for countertops, too.

Hope this information has helped.




Enjoy

The certifications that I wrote about have been compiled by the American Wood Protection Association as an acceptable industry wide standard. They are ANSI accredited and the standards are widely used by the International Building Codes as well as other organized trades associations.

In other words, some form of certification was needed and theirs(AWPA) was a good one so it was adopted.

The marine certification is C18. You won't find it in the chain stores sittin on the shelves. The dripping, warping panels in the box stores is a C2 certification, I believe. For groundwork.

When the manufacturer places the placard on our boats there is a certification involved. When we alter the original construction such as replacing stringers we have removed a permanent apperturnance(sp) and therefore voided the original and become a boatbuilder. In doing so we are culpable or responsible for our techniques and materials should a failure occur.



Enjoy

 

[seven up]

Re: Pro's and Con's of using Luan Wood

The "Lloyd's Standard" is considered one of the top building guidelines. The Lloyd's Standard of Shipbuiding.

"Built by the Lloyd's Standard" would be proudly announced by the boatowner. Always commanding a hefty price.

Lloyd's British Standard also has a wood rating for plywood.
BS 1088 and BS 6566. Voids in the individual plies are not allowed.


Hope this information has helped.

 

[Mark42]

Re: Pro's and Con's of using Luan Wood

Yes, there is a standard called BS 1088 that defines a specific type of plywood. It is not an "industry standard" for boat building or a boat certification by any stretch of the imagination. BS 1088 is tested by Lloyds of London. But, Lloyds does not specify small craft standards. They are involved with cargo ship and cruise ship materials standards. In this case, they just tests and certifies that a given product, IE plywood meet a standard that defined that particular grade of product. Lloyds has nothing to do with the small boat building industry nor do they set standards for pleasure craft or even yachts. They deal strictly with commercial shipping and cruise line ships.

1) The BS 1088 plywood is as far away from an "industry standard" as you can get, especially seeing as none of the dozen or so boat manufacturers websites I visited even mention " Okoume, Sapele and Khaya " or "BS 1088" which are the names for plywood that meet the BS 1088 rating. If they were so proud of their choice to use those products, even at elevated expense, you bet they would have it plastered all over their website, brochures and boat specifications page.

2) So, if the vast majority of boat builders don't use those products, the bottom line is that plain old p/t lumber yard plywood is as good or better than the products you will find in the majority of boat manufacturers.

3) "BS 1088" is a British standard for marine grade plywood. Period. It is not an "industry Standard". The term "Industry Standard" is so vague as to mean nothing.

How about you provide a list of American boat manufacturers that actually use Okoume, Sapele or Khaya in their boats? That would be most enlightening.

BS 1088 and BS 6566. Voids in the individual plies are not allowed.

Read them again. Voids are NOT allowed on the face vaneers. Voids ARE allowed in the interior ply's , but not more than 1 per cubic foot of ply. Voids larger than a stated size are allowed to be filled. And knots are allowed too. Voids are not allowed on the edges of the ply where you can see them. Actually, its not any better than high letter grade pressure treated plywood, except it does not have the advantage of the pressure treating.

Now that we have gotten past this fictional "Industry Standard" issue, the members of this website can rest assured that using regular plywood or pressure treated plywood will meet or exceed the plywood products that were used in your small craft, and not worry about paying exorbitant prices for marine plywood that will make absolutely no difference in the performance or longevity of your boat. And your boat will pass any "Industry Standard" inspection for certification, if you can even find one.

So all this discussion comes down to you want people to use Okoume in boats that were not even made with Okoume in the first place. What a waste of my time. I really thought that something of interest and value would come from this.

I am truley dissapointed with the way you presented you argument. You threw around terms like "Industry Standard" and "Certification" like were quoting some published documents on the subject when all the time it was just your personal opinion. When nailed down to disclosing the "Industry Standard" you were referring to, it turns out to be just Okoume plywood. Why didn't you just say "Use Okoume plywood, its rated better than lxxxxxx product".

Please refrain from this behavior in the future.

My participation in this discussion is done. Have a nice day.

 

[seven up]

Re: Pro's and Con's of using Luan Wood

Poor Mark 42 you should have yourself examined by a professional before you hurt yourself or someone else. This has become an obsession for you and is only a friendly recommendation.


Your ongoing dribble and nonsensical short stories concerning your internet research has contributed nothing.

I have listed the sources which provide the certifications.

Unfortunately you are reading only what you want. Give yourself a rest.

This reminds me of your thread about how polyester has to stick to epoxy. No matter what has been recorded in the past, for you, polyester has to stick to epoxy.




Enjoy

 

[Mark42]

Re: Pro's and Con's of using Luan Wood

This reminds me of your thread about how polyester has to stick to epoxy. No matter what has been recorded in the past, for you, polyester has to stick to epoxy.
Enjoy

Remind youself again. You are thinking about someone else. I never said poly sticks to epoxy. But again, you have fabricated a situation to try to prove yourself right, and also are reduced to insults when your own facts don't support your position.

Why don't you:

1) Now show us how smart you are by finding a post where I promote using poly on top of epoxy for boat building.

2) Show how much of an "Industry Standard" Lloyds is by providing a list of American boat manufacturers that actually use Okoume, Sapele or Khaya in their boats and have a Lloyds certification. That would prove your "certification" claims. And prove some sort of "industry standard".

But you have not been able to do any of the things I asked you to do to back up your claims. How come you can't backup your claims with facts? Why is it so easy to prove your claims wrong?

And all you did was prove you can't have a civil discussion or debate. All you can do when proved wrong is throw insults. Very childish behavor. Is this how you handle all you disagreements?

I give you one more chance to redeem your self by posting direct links to specific documents defining "industry Standard" or anything by Lloyds that defines their "Cerification" process for small pleasure craft. Otherwise, good-bye and have a nice life.

I hope this information helps with your future posts.

 

[i386]

Re: Pro's and Con's of using Luan Wood

 

[seven up]

Re: Pro's and Con's of using Luan Wood

Here's a "Best Practices Guide" issued by the American Plywood Association.

I've read this a while back but it's always a good read.

http://www.glen-l.com/wood-plywood/boatbuilding-plywood.html


Maybe this information will help clarify some information.

So it's a "Best Practices Guide".


Enjoy

 

[109jb]

Re: Pro's and Con's of using Luan Wood

seven up,

First, you are correct that plywood has differing certifications and you pointed out one such certification criteria. You are also correct that boat manufacturers must meet certain standards for certification of their products. One criteria that pops to mind that manufacturers are require to demonstrate is flotation. You are however incorrect when it comes to materials for small boats. Manufacturers are NOT required to use any certain type of material in their boats, as pointed out by Mark42, and many use non-marine grade materials in the original construction.

As I posted earlier, my 1988 16' Sea Ray had what appeared to be CDX plywood for the floor since it had unfilled knots in the face ply that faced downward. Certainly NOT marine grade plywood. You stated that using non-marine grade wood in a restoration would make me culpable if anything happened later. How would I be culpable if I use the same material that the manufacturer did??

On top of these FACTS, you also posted the following in your responses:

I guess you were out milkin the cows when the facts were written.

Either due to your naive nature or because you read "this is what everybody uses" it is nonetheless no relief of culpability.

Poor Mark 42 you should have yourself examined by a professional before you hurt yourself or someone else.

These comments come across as juvenile and do not help your credibility. As a matter of fact, these types of comment have resulted in a severe loss of credibility as far as I am concerned.