Saturday 27 July 2019

Bulkhead/Deck Reinforcement at the Hanging Locker - no more creaking.

When Windstar was being sailed you could hear creaking as the bulkhead “worked” the in overhead liner.   You could replicate this noise by firmly pushing and pulling the hand-hold at the top corner of the locker.   Furthermore, some very minor deck deflection could be detected by bouncing hard above the area.    (the deck does not yield to my 200lb elsewhere.)

Windstar is hull number 61, and the bulkhead at the aft end of the hanging locker is well tabbed to the hull, but was not secured to the deck as it is in some other 33-2s.    The bulkhead simply rests in a groove in the overhead liner, and can therefore "work" as the boat flexes.

To remedy this, it was necessary to to remove the liner inside the hanging locker, and then verify that  the balsa core and laminate were intact, especially around the fresh water fill, (which was inaccessible under the liner) and then to securely tab the deck to the bulkhead.

The photos aren’t great but they tell the story.   The water fill, locker top, hanger rod, etc were all removed, and the liner was carefully trimmed out using the Fein multitool and a bimetal blade.   The balsa core and laminate were all perfectly intact, however the putty blob used to secure the deck to the liner was cracked and the bond had failed.

Below you can see the interior of the locker, fore and aft, and can see how the boat was constructed in this area, particularly in the first photo, and how the bulkhead simply rests (restlessly) against the liner.


Below are the same views with the liner removed.   Note that I retained the inboard edge of the liner as the teak trim above the top of the hanging locker is secured there.    You can see the putty blobs used throughout the boat to bond various non-structural parts together.   You can also see that I removed the core around the deck fill.  improving the integrity of the deck around the deck fills is covered in another post.

putty removed and mostly prepped for all epoxy/glass work.

The original putty (which had cracked at the aft bulkhead) was carefully cut out and the narrow space cleaned out as best as possible, and the all surfaces were sanded and carefully prepped.The next images show the putty removed and the space between the deck and liner filled with glass filled epoxy, and next a radiused fillet of the same material added.




 And finally, the glass/epoxy tabbing was pre-laminated on sheets of waxed paper and carefully placed into to the still-wet epoxy fillets and bulkhead.  This sort of work is best done wet-on-wet as it assures a solid bond between stages.  Pics below show the layers of biaxial stitch mat laid up on a sheet of waxed paper, and then installed.




Am happy to report that the creaking has disappeared, the deck is now quite stiff.

Worth noting is that some 33-2s seem to have had the liner removed and these bulkheads tabbed in place at the factory, so I would expect that owners may have made the factory aware of this issue in early models. 

Here are some photos of Bruno L.'s 1987 33-2




To keep this in perspective, Windstar had  had seen no ill-effects or failures from this early construction method after over 30 years of use.  So, while I'm glad I did it, it was not a major structural concern.

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