Deck Creak Around Forward Shroud

[SwerlyD]

Hi all,

My father and I have owned our O’Day 28 for almost 4 years now. A concern that arose last season was the sound of the deck creaking around our port side, forward shroud (to be clear, the “smaller” one that sits toward the bow, off on its own). This is presumably because the deck core has become saturated in this area. It is particularly loud when we are sailing close to the wind on a port tack, especially when the wind is over 15 knots. Several years ago we noticed that nasty brown liquid (presumably from the rotten, saturated deck core) was leaking out from beneath the fixing on the deck. We cleaned this up and injected filler into the deck in this area, which stopped the leakage, but the creak persists, and seems to me to have become worse this past season (although it could also simply be that as I’ve become more experienced, I’ve become more aware of it).
Has anyone else experienced this problem, and figured out a more permanent solution for reinforcing it? How concerned do I need to be about the shroud tearing loose from the deck? Any advice is greatly appreciated.
Thanks in advance for your help!

 

[Davidasailor26]

I don’t know exactly what it’ll take to do a sufficient repair, but I could ask some questions that might help others give some ideas. Do you see any signs of damage to the deck skin around the shroud? On at least the 85 28 that shroud is fixed to a square plate bedded in the deck between the skins. On ours the outline of that plate became noticeable in the form of a square gelcoat crack surrounding the chainplate, though we never had creaking or other signs of water intrusion.

When you injected filler before, did you drill holes to inject into? If so could you tell whether you were drilling into solid wood or rotten dust, and did you drill out in a large enough area to get out to solid wood? Did you rebed the chainplate in any way to keep more water from getting in?

 

[jssailem]

Not sure of the exact repair action taken. It sounds like this winter down time would be good to address the issue. It is a boat. It will not fix itself. Since the shroud is a critical element to the system that holds the mast in place you will need to access the shroud base. This can be done by using a halyard drawn tight and secured a little forward of the shroud. The halyard acts like a shroud surrogate while you work on the boat shroud and deck.

Two areas of inspection come to mind. Certainly the obvious. The deck and chainplate that is holding the shroud to the boat.
Additionally inspect the tabbing in the area from the inside. Tabbing is used to attach bulkheads and other braces to the inside of the hull and deck. Age can loosen the fiberglass resins used. As the boat twists and bends during sailing the tabbing become loose and rubs (creaks) against the hull.

Inspect, assess, plan and repair as is necessary.

 

[Project_Mayhem]

Can you post some pics of the top of the chainplate, deck and anything it might be attached to down below?

 

[dmax]

I have completely redone my chainplates which I believe are similar to yours, namely Nav-Tec u-bolt chain plates. The fact that you have creaking implies the core is mush around that chainplate (not atypical in O'Days) and the deck is flexing with the mast loads.

The first thing you want to determine is the extent of the moisture in the core around the chainplate (might as well look at the other ones too) - borrow or buy a moisture meter ($40 Ryobi on will do) and run it around your chainplates (and the rest of the deck when you have time). On my boat, everyone of them had leaked and caused high moisture but it was very localized and I was able to remove all of it through the chainplate openings and fill with epoxy.

The good news is that moisture travels slowly in end-grain balsa - however, you want to get an accurate assessment of your deck before attacking the chainplate (which likely will not be fun).

I'm not a big fan of Nav-Tec chainplates but that is what the boats came with - it is a bad design that must've been cheaper for the builders as a lot of boats used them. Here's the part you can see from the deck looks like:

One of the plates is on the deck side, on my boat, the underside goes through an aluminum block that is tied to the hull. Take a look at Rig-Rite's site as they have more pictures (and sell the parts, $$$):

U-Bolt Type Chainplates

Once you know the moisture extent, you now have to go about removing the chainplate (you really should do all of them). These things are a major pain because the Stainless Steel U-Bolt that goes through the deck and uses an Aluminum block as the backing plate - a recipe for corrosion when the chainplates start leaking. Undo the bolts underneath the U-Bolt and pull up on it for the deck. Some people have been able to remove theirs through various levers, using the halyards, applying heat, PB Blaster etc. - mine didn't move a bit and I tried everything. Finally, rather than damage the deck, I decided they had to come out so I cut the U-Bolts in half and unscrewed each leg - even that took a 3 foot extension pipe for leverage and a lot of force - the threads were caked. Note that this applies just to the four lower shrouds, the uppers' chainplates are Stainless into Stainless and came right out.
Having destroyed the U-Bolts, I had Garhauer Marine make up some new ones (1/3 the price of Rig-Rite, beautiful and a better design) and put it all back together with a lot of Tef-Gel (anti-seize) and butyl bedding, better than new.

Here;s the best picture I have of the new chainplates - you can see the superior design with a much larger top-plate that is welded to the U-Bolt, no leaks:

My guess is that even accessing the underneath of the forward chainplates will be difficult - the port side one on my boat is ridiculously hard to reach. Good luck.

 

[Richard19068]

We cleaned this up and injected filler into the deck in this area, which stopped the leakage,
How concerned do I need to be about the shroud tearing loose from the deck? Any advice is greatly appreciated.

@Davidasailor26 's questions are a good start.

As @Project_Mayhem said, a few pictures from above and below would be helpful.

If you look at the bulkhead between the main cabin and the head compartment you may see the chainplate for the forward shroud. It may be set up with something like these:

5/16" U-Bolt Chainplates
5/16" U-Bolt Chainplate Assembly: CP UB-O22: Buy Special 5/16" U-Bolt Chainplate Assembly as used on later O'Day 22's. This item is identical to the original 1/4" CP UB-O22X, except that U-Bolt is made from heavier stock. Special U-Bolt Shroud Chainplate is formed from 5/16" rod on 1 3/4" centers, with a welded deck plate. Bolts extend 1 1/2" below deck surface and are secured with locknuts (included). This item was used with (2) SS Angle Brackets, CP UB-O22AB, below. As used on O'Day 20, 22 and Cal 22.

5/16" U-Bolt Chainplate - Angle Bracket: CP UB-O22AB: Out of stock Designed for use with CP UB-O22 centered on a 1/2" Bulkhead, SS Angle Brackets (2) are bolted together through Bulkhead to secure the lower end of U-Bolt Shroud Chainplate. Angle Bracket is 2 7/8" (max.) long x 3/4" wide and fastens to Bulkhead w/ (2) 1/4" bolts on 1" centers. Upper leg has 5/16" hole for U-Bolt. As used on O'Day 20 and 22.

If that's what you have and the deck fitting has been leaking there could be discoloration or rot in the bulkhead where the angle brackets attach. If there is rot there that should be addressed.