Boat floor will it stick

[dkillianjr]

Hey guys, I have a floor question. I searched the site, but really couldn't find good answer.

I am replacing my stringers and floor on my 93 crownline open bow. For the stringers I was planning on using 2"x CCA pressure treated dry lumber. For the floor I found this plywood, its CCA treated 7 ply douglas fir. http://www.marine-plywood.us/douglas fir.htm

My question is, will the fiberglass stick ok to the treated wood as long as its dry? I still plan on covering everything with epoxy before the glass.


Thanks, Dave

 

[monk-monk]

Re: Boat floor will it stick

From what i have read about pressure treated lumber, i don't think i would use it. "They" say it really never dries out...retains about 19 percent moisture...tests have shown considerable warping when fiberglass resin is applied...If i were you, i wouldn't use treated lumber...if you can afford that douglas fir for the floor, i would spend the extra money on douglas fir stringers...this way you take no risks...If you seal that douglas fir with 4 or 5 coats of resin first, then blend the stringers and the hull together with wetted out cloth...you'll never have to worry about any rotting for a LONG time..LOL !

 

[veritas honus]

Re: Boat floor will it stick

From what i have read about pressure treated lumber, i don't think i would use it. "They" say it really never dries out...retains about 19 percent moisture...tests have shown considerable warping when fiberglass resin is applied...If i were you, i wouldn't use treated lumber...if you can afford that douglas fir for the floor, i would spend the extra money on douglas fir stringers...this way you take no risks...If you seal that douglas fir with 4 or 5 coats of resin first, then blend the stringers and the hull together with wetted out cloth...you'll never have to worry about any rotting for a LONG time..LOL !

I'd be really interested in reading about this. Where did you find this information? I've got to do a small deck repair myself. Only about 12"X12". Warping won't be an issue because of the small size and the plywood will be backed by a piece of aluminum diamond plate sealed to it and coated with epoxy. I'll drill it and secure stainless steel Togglers. It will then be covered with matting, overlapping the surrounding area by about 6" and epoxied over. My pedestal seat will be secured to this at the helm... Anyway, I'll thank you in advance for the info.

dkillianjr,
Sorry, didn't mean to hijack your post... Since you're doing the whole deck and stringers, this boat obviously means a lot to you. The marine grade plywood is what you want. It's available in both pressure treated and not pressure treated from the site you supplied the link for. The jury's still out on which one's more suitable. I would say, though, the non-pressure treated would be the way to go... 1. It's marine grade, 2. pressure treated wood is generally made with lower quality wood than the equivalent non-pressure treated wood; which is why it's less expensive, even though there's more processing involved, in addition to the cost of the chemicals which are added. Hope this helps with your decision; and enjoy the project. Please be sure to take and share before and after pictures.

Safe and happy boating always!!!

 

[JB]

Re: Boat floor will it stick

Deck or sole, Dave. Boats do not have floors.

Good luck.

 

[dkillianjr]

Re: Boat floor will it stick

Thanks for the replies guys!


Ok, as I keep thinking and readng about the pressure treated, I am gonna stay away from it. I have narrowed my choices down to either MDO or marine plywood for the floor. And either doug fir or white oak stringers. Do you guys think there would be any reason not to use the white oak for the stringers? I know it has pretty good rot resistence properties.

I acctually just bought the boat, the floor felt great when I looked at it. Unfortunetly I was tearing up the carpet to replace it and just kept finding more and more rotten stuff. It ends up that the floor and stringers are all pretty much rotten. The transom seems to be solid as a rock though! And the motor only has 196 hours and runs great so I figure it will keep me busy over the winter haha!


JB, I thought of that after I posted. I'm a remodeling contractor, so I'm still getting used to these boat terms instead of house terms haha!


Dave

 

[bowman316]

Re: Boat floor will it stick

that wood is never dry. they cut it down, and make it into plywood without drying it, then seal the water inside with the sealant.

You can just tell my how heavy it is. I woulld go for a hardwood like poplar, or oak. not saying polar is hard, but harder than pine. I resined my deck down with fiberglass resin, and it stuck fine. it was 3/4 inch poplar plywood. (i think)

 

[bowman316]

Re: Boat floor will it stick

btw, you don't need pressure treated, because coating it in resin basically petrifies the wood and preserves it better than anything else can. I coated the whole sheet in resin first, let it dry, then glued it down with more resin

 

[veritas honus]

Re: Boat floor will it stick

Have you thought about cypress for the stringers? It's lighter than oak, and it's highly rot resistant. The trees live patially submerged in water.

 

[monk-monk]

Re: Boat floor will it stick

Im with bowman...you don't need to spend a lot of money on douglas fir or marine plywood. I just replaced my deck and i used an exterior grade plywood (CBX if i recall correctly) I followed West Systems instructions for resin sealing the panel first (4 to 5 coats)...and this sealing procedure should be used on all new wood employed...As bowman said, "once you seal the wood correctly, it is basically petrified"...seal each piece of wood first, it adds strength and is the foundation for which the wetted cloth can adhere to best. There is one thing i noticed while sealing the plywood for my deck...and, from what i have experienced, this applies to all cut edges of lumber, and that is this: the face or finished surface will accept resin/wetted cloth quite well, infact, it will suck it up, but when you apply the resin to the cut edges, the lumber seems to want to purge air from the end grain causing air bubbles beneath the drying resin...you have to keep a constant watch for these bubbles and keep working them out...And don't even attempt to apply wetted cloth to cut edges, you will not be able to work this air out from under the cloth, the cloth will dry and you will be left with air bubbles under dried cloth...then you'll have to sand all that cloth off to get rid of the bubbles...Been there, done that, 2 months ago!

 

[Woodonglass]

Re: Boat floor will it stick

You should ALWAYS Pre-coat your plywood with resin before laying your glass and pay close attention to sealing the edges. This will allow the glass cloth or matt to adhere to the wood without the air bubbling issues. You should also seriously consider purchasing a bubble roller to help roll the glass smooth and keep it that way. Edges are tough and need to be rolled.

I prefer MDO over all the various plywoods. It is EXACTLY like Marine plywood except for the facing material. It is flat, stays that way and is extremely resistant to water.



I'm just sayin...

 

[bowman316]

Re: Boat floor will it stick

i did not put any cloth over the resin, i just had the plywood and resin on the top of the deck. bass pro shops sells this non-skid deck paint you can cover up the plywood with later. instead of having a fiberglass deck.

 

[dkillianjr]

Re: Boat floor will it stick

Thanks again guys for all the input!


As far as sealing the wood with resin. Do you guys use hardener in the first coat, or just let it soak into the wood?

And as far as the woven cloth goes, how many layers do you like to use over the stringers after you tab them? Also haw many layers would you put over the floor seems?

Sorry if these are dumb questions



Thanks, Dave

 

[Bob_VT]

Re: Boat floor will it stick

Take a few minutes and read the information found here

http://forums.iboats.com/showthread.php?t=288451

 

[bowman316]

Re: Boat floor will it stick

i never thought about not putting the hardner/catalyst in the resin.
may be a good idea

 

[dkillianjr]

Re: Boat floor will it stick

Wow thanks Bob! I looked at those before, I must have read right past that topic.


Now when it says precoat the wood with resin, is that resin with hardener just like mormal? Or is that just resin?


Thanks again, Dave

 

[SC's Forever!]

Re: Boat floor will it stick

Hey GUYS!! GUYS!!! Using any "resin" without the hardner is like coating your "wood?" with SYRUP.......IT WILL NEVER CURE!!!!! ANYTIME the term "Resin" is used it it means Resin AND Hardner!!!!!
I hate to say this but.....READ THE INSTRUCTIONS!!!!!!
Jim

 

[Yacht Dr.]

Re: Boat floor will it stick

Wow..tough crowd here

I think SC is suggesting you use both hardener and resin In all applications..

Back to your questions..

I dont persay tab my stringers before I lam them. I have them IN dryfit then GLASS them in. ( about 3-5 layers..but Im normally working on big boys .. small stringers might take 1 mat and a few 1708s ).

I should think 1 mat and 2 1708 tabbs for your floor seams should suffice.

YD.

 

[monk-monk]

Re: Boat floor will it stick

Yes you gotta use hardner...like the other guy said...your just pouring syrup on it without hardner...

 

[monk-monk]

Re: Boat floor will it stick

Check out WestSystems products, they offer a mini pump set for the resin and hardner...the pumps dispense the correct ratio between the two and they're inexpensive...takes the guess work out of it...WestSystems have great products !

 

[NSBCraig]

Re: Boat floor will it stick

There is no need to use csm under 1708.

1708 is biaxial cloth with csm stitched to the back of it, so that you don't have to do layers of mat then cloth. It just goes down in one application and is much easier to use on flat surfaces.

Also really maybe you should spend some time reading the resources that are available on this forum. Some people went through a bunch of effort to compile them for everyone to have. They are a great resource, even though they are not perfect they are a great starting point.

I'm say this because there is zero logical reason to not properly mix your resin. It's probably the most important thing you'll learn while working on your boat, so your really better off starting out learning it right. (mix correctly, thoroughly and don't try to thin it (there are thinner resins available if the one you have isn't thin enough, use the right one don't try being a scientist and start messing with what works))

Good luck and post some pics.