Cross Frames vs. Stitch-and-Glue

In the current world of wooden boats, there are two main types of construction.  The historic method uses an internal structure with cross frames and longitudinal stringers to support and give shape to the hull planks.  A strong back or platform forms the steady foundation to mount the cross frames, generally at some equal spacing.  The boat is usually upside down for this part of the process.

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Precise mounting of the frames is crucial to build a boat with elegant, uninterrupted lines.  This is directly related to the accuracy of the foundation or strong back.  When it passes the last inspection, it is time to start adding the long parts, starting with the keel first.   Eventually, the hull planks are added to the bottom and when the structure is adequately rigid, the boat can be turned over.

For this model, I used 3/8″ plywood for the frames and cherry for the planks, mostly because I had pieces the right sizes and it looks a bit like mahogany.  Putting the hull planks in place was the most fun as it finally showed the beauty of the lines and the full shape.

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A new method of building boats was made possible by the development of modern adhesives like epoxy.  It is called Stitch and Glue, because large plywood pieces are cut to shape and stitched together, usually with wire.  Then fiberglass cloth is imbedded in epoxy to strengthen the joints and surfaces.

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Many kayaks and small boat kits use this method which works very well, if the boat has fairly flat surfaces curving in only one direction.  It is definitely a faster way of getting the hull done, but can look more boxy.  For me, I enjoyed the learning experience of making some patterns and stitching them together, but the lines of my model suffered without a good platform.

I wanted to make a wooden boat with more rounded hull and top surfaces, so narrower planking was required.  This pushed me in the direction of frames and stringers, which was fine since I wanted to learn more traditional methods anyway.  Below is the emerging boat with cross frames being mounted to the strong back runners.

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The foundation of the boat is eventually removed, but the strength and accuracy of its form has a permanent affect on the boats beauty and character.

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