Originally Posted by Ray Kay
Hi yes thanks, deck stepped with a substantial king post below it attached to a substantial GRP base which in turn forms the keel stub as in the cutaway drawing. The deck seems to have raised a bit (about 10mm) in the centre and the floor gone the opposite way. The floor seems to have dropped the same amount in the middle. If I tighten the rods all seems well if I slacken them the whole rig gets slack. I wonder if perhaps the hull has lost some rigidity over the years?
Sounds like there is a lot going on here...
The only thing that is pulling UP on the cabin
top are the turning blocks for the halyards and other running rigging
that leads back to the cockpit
. Those loads can be quite high, and there should be something helping the deck resist that force. Usually a tie rod between the deck and the mast or post below the deck? If not... there should be.
is an inherently flexible material. Having the rig slack when you loosen the tie rods is not just normal, but totally expected. The were put there for a purpose, to transfer the very high loads of the rig to the parts
of the hull most able to carry them. If they are slack, they are not doing their job, and you are asking parts
of the hull that were never designed to carry rigging
loads to do so.
It should go without saying, but do NOT sail the boat with slack rigging and tie rods. You risk serious damage to the hull or deck and rig.
If you really have questions about it, you should have a professional rigger look at it, and not have us guess about what is happening. I am betting the rig could use a good professional tuning anyway...