deck repair question

[kglynn]

I recently tore up a section of soft deck on a 1985 seacraft, ive got about a 3' by 1', section to replace, what type of wood would you replace this with, the old wood is 4x6" pieces of ply wood, I belive, should I use marine ply-wood, and cut it into 4x6" pieces, then reglass?

Thanks,
KBG

[Strider]

I'm no expert but here is what I did on my rebuild. On my deck I used 3/4 inch pressure treated plywood. I sealed it with thinned epoxy resin, installed it and then glassed it over with epoxy resin and glass. The trick to using pressure treated anything in this process is that it must be dry, dry, dry! If you have a moisture meter get it down to 10% or so. If you are going to be bolting anything through this piece of deck then you may want to go with a a/b fir ply. This will have better interior veneers than the p.t. (which is typically a/c) and will have a better back. This is what I used on my transom because I was going to bolt a bracket to it. It will be less likely to crush under pressure from bolts. Marine ply is very expensive (probably not really an issue just for one piece) but my rep at my lumber yard says it's not THAT much different than a/b anymore. Hope this helps.

[FELLOW-SHIP]

When I redid my entire deck I used pieces of marine plywood that best fit the section I was working on. One was very large almost a entire sheet of plywood and others were 1 to 3 ‘ is size. If the wood fits flat on the bottom lamination then you can use larger sizes if there is going to be air gaps between the bottom layer of the glass and the plywood you can make them smaller. My deck is very solid and I have approx 10 to 12 cut pieces of plywood that fitted in like a jig saw puzzle to cover the entire deck of my 23’ CC
FellowShip [img]images/icons/cool.gif[/img]

[kglynn]

Thanks guys, I ended up going with marine plywood, I was able to buy a half sheet for like $30, the hole cleaned up very well and the outer edges of wood dried up well, dry fitted all the pieces today, prob glass this week.

KBG

[codfeesh]

fellow ship,in this post i get that you removed the whole upper skin on your deck and replaced all the wood ...then reglassed or used the same skin?here is what im dealing with..i had a soft spot on the side of my motor box so i cut out the piece that was soft and found it was much worse than i had expected.i cut out another piece and some spots were like mud..its a 3/8 inch balsa core...but im thinking of tearing up the whole thing...now i left about 2.5 inches around the sides should i do this the whole deck and tear out all the wood..maybe you could explain your process to me ...i would aprieciate it..

thanks jeff
1974 23 cc i/o

[FELLOW-SHIP]

Ha Codfeesh
The first thing I did is use a straight edge and marked the entire deck outer edge approx ½” from where it starts curving up the inside walls of the inner linger also ½” on the drain lip in the back half of the boat. I did the same thing ½” on the opposite side where the hatch and gas tank hatch are. I did the same thing on the casting platform in the bow of the boat. I did not save the top skin I used new glass and epoxy but if you wish to save it that will work fine as well. If you save the top skin try to remove the entire top skin with out cutting it up into smaller pieces that way you can use the deck pattern and not show all the cut out job. I used a 4 ½” grinder and cut the top skin using the markers I made. Then I used all kinds of devices to remove that top layer of skin = crow bars, and such like anything I could use to pry the top layer of lamination off. Then I used again all types of things to remove the little pieces of plywood and end cut balse wood I used chisels, crow bars, grinders, sanders and 4 six packs of Bud to get it all out. I tried to level the bottom layer of lamination by adding additional glass to most of the bottom layer (extra glass where it sagged). I also cleaned out the remaining junk out of the ½ “ lip and then filled in that area with epoxy filler. Then I pre cut pieces of plywood ½” and some 3/8” thick to put over the deck. If I was going to use plywood again I “might” go with all the deck with 3/8” plywood. After I measured the little plywood blocks I felt they measured more like 3/8” than ½” you be the judge. Now you can epoxy in the bottom part of the plywood to the bottom lamination I used the glue and screw method plus bricks and other heavy items to hold the plywood firmly down. Then I filled in all the spaces between the plywood and the outer rim and between the pieces of plywood. Then you can glue and screw your old skin back on or glass new lamination level with the lips on both sides of the deck. Then fairing compound primer paint and then paint with non skid. All in all it is at least a 4 case Budweiser job.
FellowShip [img]/images/graemlins/smirk.gif[/img]

[codfeesh]

thanks for that fellow-ship,im gonna get going on that today...

[thedink9]

Fellowship
I was a bit surprised that your deck plywood meqasured 3/8 to 1/2 inch. I just took out all the core material out of my tank and livewell hatches and this material measured 5/8".
I have a CSY built 23' '85 and am about to start the deck rebuild. I'm wondering if the deck thickness is 5/8 or thinner, as you found in your boat. I assume you have a potter era hull! I'm going to reuse the top skin .

How far under the gunnel (past the point where the liner begins to turn up does the wood go? You indicated you filled this void with thickened epoxy. Didn't this mixture tend to run out?
Dink

[FELLOW-SHIP]

Ha Dink
I cant say for sure how far back the end cut balsa will go back it seems to just follow the 4 x 4 squares so if they needed to add one more block they did. As for the epoxy filler I did that for two reasons first to connect the bottom of the deck lamination to the top inner liner and to prevent any water seepage from contaminating the deck by coming in that way. I just dug out approx ½ “ of balsa behind where the top layer of glass was cut out and used a putty knife and filled it in with a thick (peanut butter thick) layer of epoxy filler. As for the thickness of the deck plywood and balsa most guys said on the Potter’s it is ½” but I measured several of them and it always showed just a tad less than ½ but bigger that 3/8” remember I built up the bottom layer of lamination with extra glass and did not use the old skin that’s why I said maybe I would use 3/8 if I ever did it again. You want the deck to remain at the same height when you are done so it will match the two lips you created when you cut out the deck portion.
FellowShip [img]/images/graemlins/grin.gif[/img]

[thedink9]

Fellowship
Did you level the lower skin with thickened epoxy and add a layer of glass for added strength before you began to add the wood back into the deck? If so, what type of glass cloth did you use, both under as well as over the wood before you built up the outer skin?
Dink