Lofting, Continued

At this point the lofting is moving along nicely. The photo to the right shows the body plan complete. Note the base line is defined by the 1 1/2" strip tacked to the base of the lofting. This is a great help in butting your straight edge against while marking points on the lofting.

At the top of the body plan you can see the sheer and waterlines drawn in Half Breadth view. The remaining lines to put down are the Butts in the profile and to check the Diagonals by drawing them in a Half Breadth view.

At this point, laying down the Butt lines will be done next and they will reveal the fairness of the body plan sections in the fore and aft direction. Because the pram is small, there can be some unfairness in the the sections in the body plan that examining the butt lines will reveal. If you see a bump or flat when you lay down the butt lines in half breadth view, carefully examine, that portion of the section line to determine the source of the unfairness.

For me, one important thing to remember when I haven't done any lofting for a long period of time is to remember that each line in the lofting has a proper place to begin and end. It's usually easy to lay down the points along the line but ending them in the proper location is key to the accuracy of the lofting. And, more important, is that all the line are inter-related and are meaningful in developing other views necessary in building the pram. For this pram, the lines and offsets provided in the Gardner article were "to the inside of the planking". It's important to fully understand the difference between this basis and when lines and offsets are to the "outside of the planking". If you are lofting, carefully read and study your plans before starting because all the information will be provided. Sometimes I find, it is a hunt for important details, but they are usually provided.

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Building The 10' Herreshoff Pram

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A 10 ft. Herreshoff Pram

This Blog is about boatbuilding and this is the beginning of the construction of a 10 ft. Herreshoff Pram. I chose this plan for its simplicity and when built of well chosen materials will be a classic pram finished fancy with varnish. I became aware of this pram while reading John Gardner's "Building Classic Craft", a book I have had for years and have enjoyed reading Mr. Gardner's descriptions of the many varied small craft and learning of their origins. The pram will be traditionally built with cedar lapstrake planking over steam bent oak frames. This planking will likely be of Northern White Cedar which was traditionally used at the time these boats were built and in service in the Northeast part of the country in Herreshoff's period. I haven't built a boat from descriptions and plans contained in an article previously but the plans look complete and offer detailed information of the boats construction thanks to the expertise of Mr. Gar

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