One of our customers at Manchester Marine has been the owner of a Concordia 39 for many years. He has lovingly used her and cruises extensively in the Northeast. She came to us having been previously restored (very well, I might add) and in very sound condition, but as most wooden boat owners know, even the highest quality original construction and a thorough restoration don't result in the end of ongoing repair or restoration work.
During the time the vessel has been under our care we have worked with the owner and his surveyor to stay ahead of issues presented by traditionally constructed wooden boats. An extensive re-fastening program has been broken into multiple phases, and a handful of planks below the tuck have been replaced on both sides of the vessel. Floor timbers, stern post, frame heels, and other structural issues have been addressed during the course of what we can call this "maintenance regimen."
The winter of 2011 has us stepping things up a notch. We are replacing all of the laminated sister frames on the port side, from the cockpit bulkhead to the forward cabin bulkhead. This is a project that involved a great deal of "front-end" work. We (the owner, the surveyor, and the crew at MMC) all knew that it was very likely that we were going to find an issue with these structural members. James, the carpenter on the project, has done this project on another Concordia, and we know that many of the other sister vessels have dealt with the same problem.
A bit of history: Abeking and Rasmussen originally built the Concordias with only bent frames. The frames are about 1 5/8" square, tapering slightly from the turn of the bilge to the sheer clamp. Due to a number of factors - the very hard turn of the bilge and tight-seam planking being the main contributors, the original frames were found to be cracking on many boats shortly after initial commissioning. All of the boats were then fitted with laminated sister frames to remedy the situation. At some point during the construction run, the bent frames were replaced with all laminated frames. I don't know specifically whether the boats built with laminated frames also got the sister frames. The sisters were carefully fitted and fastened in the middle of the frame bays (except where butt blocks and/or chainplates interfere) and they were an effective solution to the original problem. Over time the glue in the laminations has failed with the result being a stack of laminates held in place by a handful of screws. Movement of the planking at the turn of the bilge has been evident in topsides finishes.
We started a dialog about tackling this project a few years ago and we spent time between then and now doing research, planning the project, and estimating the work. James' previous experience with this repair has proven to be invaluable. We could not have possibly gotten everybody on the same page about the nature and scope of the work without his ability to accurately quantify what we were likely to find and how we are likely to address it. There is no substitute for experience.
Once we had our ducks in a row, it was time to turn to the actual project. The boats were built very well. Importantly, they were put together intelligently with a cohesive plan for accessibility for future repairs. All of the interior joinery comes out as "modules," and the ceiling battens extend from bulkhead to bulkhead. This allows for very easy disassembly and un-obstructed access to the interior of the hull surface. Once the work area was stripped, the urgency of this repair became apparent.
From here out, the work is pretty straight-forward. We stripped the topsides to expose the fastener locations and began the removal process. Every other sister will be templated, laminated (black locust glued with epoxy), fitted, and fastened. The remainder will then be done. This will help to ensure that the hull shape is retained, and that no undue stresses are placed on the already cracked bent frames.
The photos show the process pretty well. We started by stripping the topsides finish in the work area to expose the fasteners. Next came disassembly of the interior components as needed for access. Ceiling strips were numbered for re-installation and the owner took them home for finish work (along with a few other interior parts). Note the delaminated sister. I did not get a good shot of the cracked frames. I'll try to get one in a later post.
