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Frame Work


Inspect and Strighten Hull

The first consideration is to determine whether the hull is straight, plumb, and level. Hulls that have sagged, twisted, or spread are said to be "hogged." Having repaired more than 100 wooden hulls, I have never seen one that did not need to be pulled or pushed into shape somewhere.  This is not surprising given that these wooden boats have outlived their intended lives by many decades, most without minimal care.  Even proper blocking will distort a hull if it sits there for decades.Click for larger photo
Click for larger photo I have heard many times from people who have found a boat they want restored and proclaimed proudly that the boat has been "in storage" for 20 years, as if this has somehow preserved it.  On the contrary, phrases like "long-term storage" ring alarm bells.  All boat hulls are designed to displace water in order to support their weight.  This means that the hull was built to be supported at all points of its bottom surface.  Out of the water, hulls are inevitably supported at a few points.

Temporary winter blocking, as directed by the factory owner's manuals, generally puts all the weight on three points of the bottom.  If left to long in this position, the weight of the transom, fuel tank, and running gear typically causes the stern to drop, creating a longitudinal concavity in the supposedly straight planing surface.  When run in this condition, the bow is forced down and can cause plowing and dangerous attitudes when cutting across waves or wakes.

If the support blocking is set farther aft to support the transom and left this way for years, the weight of the engine causes the center of the bottom to drop creating a longitudinal convexity in the supposedly straight planing surface.  When run in this condition, especially at higher speeds, the boat keeps trying to climb up on it's curved planing surface only to reach a point where the weight of the vessel drops the bow back down, over and over again.  This performance is usually referred to as "porpoising" or "hobby-horsing," which is not only maddening, but leaves you half out of control and unable to see over the bow.  Many have tried to correct this condition by adding wedges or shingles to the after-edge of the planing surface at the transom to force the bow down.  This method works to some extent but is analogous to using water brakes and really only creates the concave planing surface previously mentioned.

If your boat has an original bottom and frames and is more than 20 years old, even a single season of improper storage could cause these conditions to appear.  These are just a couple of reasons why it is so very important to properly address the framework of the hull when restoring a boat.  With the boat upside down and the bottom planks removed, frame repair is about as easy as assembling Lincoln Logs with screws.  These boats are merely large model;  think of them as such.

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