DECK DELAMINATION

Tim Lackey, #381, Glissando

Unscientific as it may be, sounding the deck is the best way to determine what's going on inside. The flex underfoot coupled with the hollow sound you get is an absolute indication of the debonding. It sounds like the PO did a lousy job in replacing the top skin of the deck, as the core seems to be OK beneath, but the top skin has already released from the core.

Remember this about sounding: if the outside temp is below freezing, like it pretty much is between November and April, any saturation in your deck may well provide a "solid" sound, rather than the dull, almost mushy sound it will when the water is thawed. Beware of this limitation as you search for other areas, until the weather warms again. All this means is that it is possible that you might miss an area of saturated core by sounding only, as it might seem more solid than it is. The hollow sound, though, will indicate debonding/delamination regardless of the outside temperature.

Mike Lehmkuhl, Renegade #3, ATHENE

Before repainting Athene, I noticed a number of bubbles (or blisters) in the gelcoat on the deck. Cutting away the top skin in these areas revealed that while the top laminate continued to adhere to the core, something in the layup process prevented the top couple of layers and gelcoat from adhering to the layer directly on top of the core. The problem was the deck had bubbled up ever so slightly in these areas and while they remained unbroken, could crack and let water into the core of the deck eventually.

To fix this, I ground out the offending "blisters" and refilled with fiberglass and epoxy, refaired and painted. Depending on the size of the areas you suspect may be the problem, there isn't much difference cosmetically between drilling and filling small holes and grinding out and refillling one big one (mine were approx 4" or 5" square areas)... You will still need to repaint the area.

James Baldwin, #384, Atom

Below is a paragraph regarding Atom's delaminated deck from the article Twice Around in a Triton in a recent issue of Good Old Boat. Actually, much of what I wrote was edited out of the article. If anyone here would like a copy of the full article, I can email it to you as an attachment.

" Many Tritons suffer from waterlogged balsa-cored decks. Water enters through leaking deck fittings and eventually rots the balsa core, causing it to delaminate. The first symptoms are leaks at chainplates, stanchion bases, and jib-sheet tracks. You can re-bed the fittings, but because the core has absorbed water, before long, the leaks reappear. Eventually, the core breaks down entirely and feels spongy underfoot. The only permanent cure is to replace the deck. I began this enormous job by removing every deck fitting and cutting off the deck's upper fiberglass layers using a circular saw. After removing bucketful's of stinking balsa mush, I laid down a layer of epoxy-saturated fiberglass cloth. I then cut ½-inch polyurethane sheets into 4-inch squares and set them into the deck in a thickened epoxy filler. On top of this I spread another layer of filler and laboriously block-sanded it until level. I covered the deck with five more layers of fiberglass cloth and epoxy resin, repainted it and reinstalled the deck hardware. It was a miserable job I had been putting off for a long time. But having an absolutely dry boat inside made it all worthwhile."

I did not have room in the article to go into more detail, but of course there is a lot more to the story. I first tried several ways of repairing the deck with no success. My main problem was deck leaks and I found nothing short of replacing the entire core would stop the leaks.

On the cabin top or coachroof I only cut out portions of the top around the handrails and inserted plywood in the core to provide strength for the handrails mounted inside and out. In my boat the core in the coachroof was hollow. The cabin liner had gaps between it and the top layer. I don't know what other Tritons have.

Some points to consider:

1. Is the deck core dry everywhere? Is it undamaged by any kind of so-called "dry rot"? If the core is not in good condition, your epoxy resin will not adhere well to either the core or the top or bottom deck layer.

2. Are there any leaks around deck fittings. If so, do they reappear soon even after rebedding the fittings?

3. Has the deck warped in the delaminated area? You say the deck has delaminated. I am guessing that you would not know if it delaminated unless the core has been crushed due to some type of rot or that the upper layer of the deck has seperated and warped up.

4. Has the bottom of the deck sagged in places?

5. What are you hoping to accomplish? If there are no leaks and only slight flexing of the deck underfoot then I would consider myself fortunate and do nothing.

Mark Parker, #516, All Ways

When I bought All Ways (then Northstar) her deck was severely delaminated - the whole cabin top, both side decks and a section of the foredeck. On the cabin top, I cut off the whole top, scraped out the rotten core (nearly all), replaced with Airex and rebuilt the top with several layers of bi-ply. For the side decks, I cut 4" holes out of the deck, removing about 50% of the surface, removed the rotten core, replaced it with new Airex and epoxy replacing the disks I had removed then ground the whole thing flat and added another layer of glass over the whole deck. Finally I covered the deck with laid decking of Trex (called faux teak in the article in Good Old Boat). Alternatively, you could paint and add non-skid (but the Trex does look classy and is great to walk on - no skid but no sandpaper either).

Having done it both ways, I would recommend the circle method. It was easier to get a fair result than when there was no structure to go by.