garymalmgren said..
Alan
From you explanation it seems that there is a flange of some sort glassed to the underneath of the cabin top.
This would have been done when the deck/cabin top was still in the mold.
If I am reading you correctly , the bulkhead is fixed (not to securely) to the flange with screws.
Could it be that over the years the screws have enlargened the holes in the flange or in the bulkhead thereby allowing movement and your noise?
Would larger screws or machine screws with dome nuts fitted tightly to new hole fix it?
I may be right off the mark with that suggestion.
Bulkheads fully glassed to hull and underneath deck/ cabin top are not unusual at all and would enhance the strength of a boat by compartmentalizing the construction.
gary
Thanks Gary - you're right, there is a sort of flange in the cabin top into which the screws were embedded. But as I said, the self tappers used had been intentionally shortened so they were only about 5mm longer than the bulkhead width (about 18mm) - why, I don't know.
This is why I thought maybe the screws were just cosmetic.
Even so, I decided to replace the screws with the correct length so that they rigidly fixed the bulkhead to the flange. This cured the creaking for a while - but it started creaking again after a few weeks!
This led me to think maybe it WAS meant to be floating and what I needed to do was to insert some sort of spacer to silence any movement between the bulkhead and flange.
so, any thoughts very much appreciated
regards,
allan