Tom, many C&C 36 and 38 from around that year have had similar problems. I have the same model and year of boat as you have, and I am relatively new to it as well.
Part of what your are experiencing is just the "natural" reshaping and relaxing of the hull and deck in response to stress over time. When in the water, the weight of the keel and the load of the rig tension pushes the mast step and the hull surrounding the keel down relative to the rest of the boat. The mast straps, (which are occasionally and erroneously referred to as the partners), are attached to the deck and pull it down to the extent that the mast step moves down relative to the rest of the boat. When the boat is out of the water these forces are either relieved (rig tension) or reversed (keel weight) and the boat will take a few days to settle in again once back in the water. These effects need to be taken into account before considering any remedial or restorative action. Jacking up the mast a little bit to get the bolts in may be the best solution if it is not too far. A small amount of load on the deck may not be a bad thing. On my boat I think it is a bit too far since the deck appears to be depressed around the mast collar by more than 1/2 an inch. I can not see anything wrong with the transverse wood and fibreglass supports immediately ahead of and behind the mast step box. What I have been told is that sometimes the space under the box was filled with more or less random bits of wood. fibreglass, and resin to build up a support platform, and that the sinking mast syndrome in that case is due to that wood rotting and probably not structural in any sense other than the loss of a shim under the mast. I have not decided what to do with mine yet, but there is a 1978 C&C 38 at our club which had a piece of aluminum plate cut to fit inside the step box, and it has worked fine for a couple of decades now. That will be my solution unless I find a good reason not to do it. I too would welcome further information or experience from others who have dealt with the same problem on the same or very similar boats. Steve Thomas 1980 C&C36 Merritt Island, Fl ----- Original Message ----- From: Tom Alessi via CnC-List To: cnc-list@cnc-list.com Cc: Tom Alessi Sent: Tuesday, August 02, 2016 12:30 Subject: Stus-List mast collar straps Hi, This is my first season sailing after a season on the hard doing repairs. When the yard re-stepped the mast the holes on the metal straps that bolt through the mast no longer align. The holes on the mast are lower by 3/8". As part of the rehab I had removed the mast collar. so I initially thought that I used too much caulking in the installation. I removed the collar and scrapped away all the caulking but the holes are still off. I wasn't there when the yard had originally took out the mast so I'm not sure if there was anything under the mast causing it to be slightly higher. I'm relunctant to drill a new set of holes. Any advice would be appreciated. Thx Tom Alessi S/V ANDIAMO C&C 36, 1980 Rockaway Bch, NY 646-283-1580 tagraph...@optonline.net
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