plywood question

[fishrdan]

To help the CCA plywood search.... Pontoon decking is CCA treated plywood, or another brand is Plydek XL. I seem to remember that Gander Mountain and Cab-elas up in your neck of the woods carries Plydek XL. Though, as I remember, only 3/4" was available.

Untreated doug fir "marine" plywood is a better quality of plywood than CCA treated (as far as I've been able to determine) as the marine doug fir has the plys laid at 45* for better structural rigidity. It also has all knots football patched for practically no voids. (I say practically as I found voids in my marine plywood...) I haven't seen CCA treated pontoon decking, but seriously doubt it's the quality of doug fir marine plywood. The CCA treated stuff in my 2001 Crestliner looks to be an AC or AB plywood. Good enough quality for an aluminum boat interior, I guess...

 

[bonz_d]

This is something all of us need to deal with from time to time. In this particular case the issue, at least for me, is the dimension of the plywood and the number of plies.. Also agree that the conditions, exposure and overall care plays a major part in how it will hold up.

From what I have read over this weekend about encapsulating in expoy is that any, again any, spot that is penetrated once finished has been compromised. Whether it be a bolt, screw, staple or even a hit that causes a fracture that cannot be seen. I have also read that the correct way to install it encapsulated is to lay it all out, make all cuts and predrill all revit holes before appling the epoxy. It was even stated that the rivet holes should be made large enough that they do not need to be forced thru the hole or it could compromise the seal..

 

[undone]

Making sure everything is sealed when you're done is an issue, That's one reason why I prefer not using any product (vinyl or carpet) over the wood, just use epoxy and a some type of non skid added and paint, easy to do, and easy to repair. Coat the bottom with epoxy and use something like 5200 where you expect to put fasteners, put the fasteners in and the apply the epoxy over them on the top side. The other option, which can work well, is forget about trying to make it last forever, cut the plywood (your choice on the type) to shape, paint with porch paint with non skid and call it good, many times you don't even need to fasten it place, it's not going anywhere. This method is cheap and easy, plus if it goes bad in 10 years from being left outside in the weather it will be cheap and easy to do again.

 

[jbcurt00]

..Neglect, that's a great maintenance plan ^^^^ And what? Just 'deal' w the water logged foam and every other wooden structure in the boat too after leaving it out to weather? Bonz: sounds like you've spent some time doing the research to hwlp you decide for yourself what's the 'best' way for YOU to seal YOUR boat's wooden structures. GREAT! IMO, that's the best way to go about this business of rehab'ing old boats. I commend you for taking the time to DO the research and POST your impressions of what you found. Thanks.

 

[undone]

"Neglect, that's a great maintenance plan ^^^^ And what? Just 'deal' w the water logged foam and every other wooden structure in the boat too after leaving it out to weather?"

You seem to read things into a post that aren't there, I didn't say you "should" leave it outside, I said "if it is". Plywood tends to last 5 years or so even if nothing has been done to protect it, with paint it may last 10 years if neglected. You maybe have $100.00 and half a day of work invested the cheap route, If kept inside this method may hold up for decades. Not pretty, but it works. Most of these small aluminum boats don't have a sealed deck, water flows around the edges and onto whatever type of foam is there, so it's going to be wet no matter what you do. Plus most small tinnies use blocks or sheets of EPS foam in the seats or boxes, not two part sprayed in the hull, although some do use a combination of the two. Some also have sheet foam under the floor.

 

[jbcurt00]

IMO, the only part that was imimportant QUOTE=jbcurt00;n8461551]Bonz: sounds like you've spent some time doing the research to hwlp you decide for yourself what's the 'best' way for YOU to seal YOUR boat's wooden structures. GREAT! IMO, that's the best way to go about this business of rehab'ing old boats. I commend you for taking the time to DO the research and POST your impressions of what you found. Thanks.[/QUOTE]

 

[Woodonglass]

Here's what I KNOW from Life Experience. When I was 14, (1964) my uncle and I built a 12 ft plywood flat bottom boat for his fishing pond. We built it in his barn. I helped he did most of the building We used 3/8" Ext. Grade Plywood (I guess, not sure) We did NOT seal the plywood. We used Window Caulking that he had laying around to seal the seams. We used Ring shank(I remember He made a Big deal about telling me that using these nails they'd never pull out) Nails to nail it together. We used Green John Deere Tractor Paint to paint it.(That's what he Had) It Floated, used a 36lb Trolling motor, It did NOT Leak, I caught a LOT of fish out of it, I put a fresh coat of paint on it every spring, till I was 18. It was stored leaning up against the Hay Barn where we pulled it up from the pond with the tractor every late fall. I don't remember ever making ONE repair to one rotten board or fixing one leak. When My uncle died When I was 36, that old green boat was still there, leaning up against the hay barn. I went down and checked on her. Looked good as new. My aunt said my Uncle fished out of her the year before and she couldn't ever remember him doing anything except putting a fresh coat of John Deere Green Paint on her every year. Not sure how thick 22 coats of paint is but.. If you take care of and Maintain your boat...It will last!!!!

 

[mercurymang]

Here's what I KNOW from Life Experience. When I was 14, (1964) my uncle and I built a 12 ft plywood flat bottom boat for his fishing pond. We built it in his barn. I helped he did most of the building We used 3/8" Ext. Grade Plywood (I guess, not sure) We did NOT seal the plywood. We used Window Caulking that he had laying around to seal the seams. We used Ring shank(I remember He made a Big deal about telling me that using these nails they'd never pull out) Nails to nail it together. We used Green John Deere Tractor Paint to paint it.(That's what he Had) It Floated, used a 36lb Trolling motor, It did NOT Leak, I caught a LOT of fish out of it, I put a fresh coat of paint on it every spring, till I was 18. It was stored leaning up against the Hay Barn where we pulled it up from the pond with the tractor every late fall. I don't remember ever making ONE repair to one rotten board or fixing one leak. When My uncle died When I was 36, that old green boat was still there, leaning up against the hay barn. I went down and checked on her. Looked good as new. My aunt said my Uncle fished out of her the year before and she couldn't ever remember him doing anything except putting a fresh coat of John Deere Green Paint on her every year. Not sure how thick 22 coats of paint is but.. If you take care of and Maintain your boat...It will last!!!!

Great story.

 

[bonz_d]

Yes I too grew up at a time when Chris Craft, Correctcraft, Century, Owens,Lyman, Thompson and a whole bunch of others were building plywood boats. Some of then quite large. Many of those cabin cruisers used vinyl to cover their decking yet I don't recall a one of then that epoxied over the plywood from the factory. Some of those boats are still around today! A different type of art as compared to todays offerings.

As to the one I will be working on it appears that the PO of this boat did just what undone has mentioned and just painted it all with porch paint. Don't know how long ago that was but I can guess it was more than a few years ago as I've owned it now for 2 years. The piece I already pulled up was still intact and dry. Doesn't look pretty but it's still sound.

It still amazes me that a question regarding which plywood to buy has turned into all this.

 

[mercurymang]

You think that's bad. Go over to any one of the motor sub forums, grab some popcorn, and ask "When should I change impeller?".