Questions on finishing a plywood deck

[Acpics80]

Hi guys, a few questions about finishing the new decks for my Sea Nymph. I've cut the new deck out of 1/2" exterior grade plywood and sealed the top and bottom surfaces with 2 coats of "old timer's formula" and the edges at least 4 times. I then coated all surfaces with two coats of spar varnish, but now I'm a bit undecided on how to "finish" them so I have a few questions.

Has anyone used any type of paint over spar varnish? I'm assuming for this to work you would need to sand the surfaces well and then use some type of oil based paint. A friend of mine has some extra textured marine decking paint so I was thinking of trying some of this on a sample piece. Just curious if anyone out there has done something similar.

I also found a product at the local hardware store that is essentially sand and you mix it with your paint or varnish and then apply a coat. I tried this on a sample piece and it actually turned out very nice. I think it would be a great non-slip surface I'm just not sure how I would like the look of a plywood deck.

Lastly, I'm a bit confused on how to seal the seams between my deck pieces and around the edges of the deck with the painted aluminum hull. I've seen the term "PB" tossed around on here but I'm not sure what exactly that is other than referring to the consistency. Does anyone have suggestions on what I can use on the seams in order to seal up the deck?

To secure the deck I plan on using ss screws with finishing washers. For the majority of the time this boat will be in the salt and fishing so carpet is out of the question for me.

Thanks in advance for any help, tips and suggestions!
Acpics80

Picture of the new deck before it was removed again to seal:

 

[Woodonglass]

I've used Rustoleum Pro Oil Based Paint over the OTR with GREAT success!!! PB is just polyester or Epoxy resin thickened with Cabosil or Wood Flour to the consistency of Creamy Peanut Butter. You then trowel it into the seams to fill them. Works really well. For texturing the deck I've rolled on the Rustoleum and then punched nail holes in a coffee can and filled it with sand and applied the sand to the wet paint. Let it dry for a few hours then rolled on another coat and applied a bit more sand and then rolled on another couple of coats. That gave me a nice texture that wasn't to rough on bare feet.

 

[Acpics80]

Thanks Woodonglass, that's good to hear that Rustoleum paints will work! That marine deck paint is crazy expensive, I was hoping to avoid it. I think PB and Rustoleum with sand will be the route I take. Thanks for your input.

Cheers!
Acpics80

 

[Tnstratofam]

Can you pb the deck to the sides of an aluminum boat? I thought pb was only used on fiberglass hulls.

 

[TruckDrivingFool]

He's speaking of filling the seams between the individual deck pieces, but I suppose you could fill gaps between the deck and the hull too.

 

[Tnstratofam]

I didn't realize it could be used between the deck and hull on an aluminum boat. Always learning something new.

 

[Acpics80]

He's speaking of filling the seams between the individual deck pieces, but I suppose you could fill gaps between the deck and the hull too.

Hi TruckDrivingFool, yes, I was wondering about both, the seams between the deck pieces and also the seams along the edge of the deck and the hull. If I can use the PB mixture for both that would be great.

-Acpics80

 

[jbcurt00]

I didn't realize it could be used between the deck and hull on an aluminum boat. Always learning something new.

I wouldnt fill the hull/deck seam w PB, that should be on glass boats, not tin.

If you want to fill the joints/seams between sheets w PB you can, even go so far as to glass over the seams too.

BUT I think you'll find the OTR makes it difficult to get a good bond along the edges of the plywood, and probably should be sanded to bare plywood if you plan to leave any PB on the face of the plywood to feather the joint or want to embed glass over the seams.


If it were mine, I'd make sure the seams are extremely well sealed, well secured along both sides of the seam, and leave them alone to be painted. You might want/need to remove panel A but no others at some point. Filling the seams makes that more difficult.

Or use 3M 4200 (or similar) to caulk the seams and be done w it.

If the deck is a good fit to the hull, I'd probably leave it open too. Or again use 4200, but definitley not PB.

 

[ondarvr]

PB has no place in your project, if you need the seams sealed use a paintable caulk.

 

[Tnstratofam]

So just to get it straight in my head, and to be sure the op gets their original question answered. You can use pb to seal between the deck boards themselves ( Although not recomended as 3m 4200 or paintable caulk will suffice ), and you can't or shouldn't use it between the deck and the aluminum hull along the perimeter ( Again 3m 4200 or paintable caulk will suffice.) I assume some use pb on aluminum boats when glassing the deck for waterproofing.

Sorry Acpics80 not trying to hijack your thread just confused.

 

[jbcurt00]

IMO, you are correct Dave

To further clarify, I was referring to Epoxy use for both PB and glassing over seams, not polyester resin based PB. But I suppose poly based would work too...

 

[ondarvr]

So just to get it straight in my head, You can use pb to seal between the deck boards themselves.

No. PB (putty in the real world) is weak and brittle, it would crack immediatly when you got in the boat and the plywood flexed. If the plywood was going to be glassed over it would be OK.

 

[Woodonglass]

Well, to clarify my post, I totally MISSED the fact that this was a TINNER!!! Even So Epoxy based PB in my experience does not cure weak and brittle. Polyester PB will unless you add glass strands to the mix. I will say however I did expect the seams as well as the deck to have some sort of glass laminated over them. I was NOT speaking to the Hull-Deck seam around the perimeter. ON an aluminum boat I agree I would not recommend sealing this joint and If you did It would be with some sort of a Flexible Marine Sealant such as previously mentioned.

 

[mxcobra]

Why not use pl premium for the application

 

[Acpics80]

So just to get it straight in my head, and to be sure the op gets their original question answered. You can use pb to seal between the deck boards themselves ( Although not recomended as 3m 4200 or paintable caulk will suffice ), and you can't or shouldn't use it between the deck and the aluminum hull along the perimeter ( Again 3m 4200 or paintable caulk will suffice.) I assume some use pb on aluminum boats when glassing the deck for waterproofing.

Sorry Acpics80 not trying to hijack your thread just confused.

No need to apologize, I was a bit confused myself and it's a good convo.

4200 or something similar it is then, as long as it can be painted.

It seems that some of you recommend not sealing the area between the deck and hull. Why is that, is it because of flexing with a tinny hull? I'm leaning towards sealing everything tight, forcing water / fish slime to the stern and into the bilge. I'd prefer not to have that mess running below my decks throughout the boat.

 

[Watermann]

The 1/2" ply will flex from your weight walking on it, not so much from the hull flexing and I can't see a reliable way to use goop to seal seams and sides. It's not going to be like an aircraft carrier. To have what you want painting the deck isn't the answer, I think you would need to use a marine vinyl deck covering to cover the seams and go up the sides a few inches.

 

[jbcurt00]

Lots of good info in here, another discussion about sealing the hull to deck joint:
http://forums.iboats.com/forum/owne...-does-the-floor-join-to-the-hull-at-the-edges