stringer lumber

Find out where the local pro's get their lumber. Douglas fir.

Ok, may step In a pile of dog doo here, but I have seen you guys talking about using lumber in a build. have you guys considered using plywood before? Marine grade ply (maranti, okoume) are IMHO superior strength wise versus traditional lumber. There's also a company called plum creek that manufactures a marine ply that is pressure treated, but then RE-DRIED in the kiln so that resin will adhere to it. That stuff has superior rot protection in addition to great strength.

Just throwing it out there...

I've only seen it used where the layers are placed perpindicular to the hull, obviously creates more strength as you noted. Regarding hardware I think you'd be fine, but again, I'm asking, not telling...

That being said, it's ALL I have ever seen used on other rebuild sites (when wood is used) that are non-ski boat related.

No on the ply. As mentioned due to every other veneer layer having the gain of the wood in the wrong direction, you will not get the strength needed. Also, where would you find 14' long plywood? You would need to scarf and stagger the joint but you would still have the grain problem.

Yes on the LVL. All it's veneer layers run the length.

No on the treated. It's not the moisture that hurts the bond.

As promised. This is just the first one I found this morning...

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

I actually found real nice douglas fir at my local menards, they have a good lumber selection. Keep checking around Im sure you can find a good lumber yard, in general big box stores will not have what you want, I just lucked out.

TRBenj wrote: LilRichard wrote: Regarding the strength, so many boats were made factory with ply stringers it would take all day to list them. How many were inboards?

Tim has the real answer here... do not try to compare the stringer requirements of transom mounted engine boats OB or I/O with v hulls to flat bottomed inboards with the drive train located midships. Plywood stringers rot.. badly. If you are willing to cut and laminate then as mentioned above you should use coosa or similar, for a couple hundred bucks more you would have a much better finished product.

I don't disagree with coosa... It's a superior product. I went foam filled in my boat for longevity, composite is the way to go... But it's a less forgiving methodl than wood.

That mako is an obvious example of the difference in stringer requirements between a flat bottom ski boat and a deeper v hulled boat. Those very large bulkheads combined with the shape of the hull transfer all the loading to the hull side walls very effectively.   The stringers do not serve the same structural purpose as those in a Ski Nautique. IMHO Coosa is more forgiving that plywood in every possible way.

JoeinNY wrote: MHO Coosa is more forgiving that plywood in every possible way.

Pls see two posts above yours... I don't disagree.

Roger,
That is an interesting concept with the laminating to build the height. Did he comment about CPES? Did you use it?

YooperSully wrote:    This guy grew up in the marine industry building Donsi (spelling) boats. Off shore racers. Boats that do 80+ over choppy ocean waves. When I explained my project to him in the beginning I was planning on using epoxy.

If you have spent any time on the Donzi site you will find people,like here, are even pulling decks off and built in fuel tanks to repair rot. Some of their core wood is or I should say was balsa.

Sorry for thread jacking this. This will be my last off topic post on this thread, but Peter, I might need to brush up on Ohms law,because I get unvalidated resistance from you. I don't know much about Donzi but on any level of common sense, if you can stick a 43' boat out in the ocean with 1025 horsepower and it returns back to shore after doing 80 MPH+ over choppy seas time after time. That build method is good enough for me. Yeah I get it that people are tearing their boats apart and fixing issues, but profitable companies don't build product to last forever. There is always more than one way to cross a river. Just because you floated a log to cross doesn't mean everyone else has to. Go buy a steel ship, much superior to a fiberglass vessel and 20-30 years down the road you're still going to need to give the hull and structure repairs. If cheap repairs with cheap products combined with good craftsmanship get the job done, then I'm on board. Why spend more money on materials than you need to? His repairs hold up. Plain and Simple. His poly work has held up for years on boats bashing around on Lake Superior. Plain and simple, Poly or Epoxy, this is America, I thought individuals had the right to choose? I have yet to read a post where someone is saying "I used poly and it just came apart"

CPES is an epoxy product. So if I'm laying poly over the top of it, it isn't a compatible combination.

YooperSully wrote:    I have yet to read a post where someone is saying "I used poly and it just came apart"

I guess the fact you had to replace yours it's already been said If you didn't use foam you'll probably be allright and the chances you'll keep it as long as Pete keeps a boat any way are remote