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| Lines for 12'8 punt |
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The design is based on feedback from the larger banks dory. The dory is a good boat, quite fast and seaworthy. However the downside is that it is a large boat and is affected by windage quite a bit. It is also a fraction heavy, with my estimate at present being 70kg. The new design is thus meant to have much lower windage and be light enough to cartop. It is only designed for calm waters ant not large swells. I have gone for a punt design rather than a conventional dingy so as to make it shorter and thus easier to cartop. I have tried to optimise it for 1 person rowing on calm water. It is hoped that this punt will go very well with 2 people on board, and with the very occasional three people. With the idea to optimise to one or 2 people I have thus lowered and lowered the sheer line over time to reduce windage. Midsection freeboard is 24.5cm at 200kg, 26cm at 150kg and 21cm at 300kg. This still seems reasonable so I may cut it down another cm or two, depending on feedback I receive. In part I am inspired by the light Steve Redmond Whisp, in part by the 'Little-Peter' punt by William Atkin. I would also like to express my appreciation to Steve Lewis who provided a punt design from which I changed and changed to get the present lines. One consideration is the wind here in Melbourne often I would like to go rowing but the dory being affected by the wind makes it a hard process. Thus the punt is designed to be long and narrow and thus fast to row. There are not large waves here on the river thus high freeboard is not essential. The new design has a bottom panel at 82cm width, which is about 15cm wider than my dory. The idea is to provide more initial stability for those less agile than myself, whilst still providing for a fast hull by not going too wide. Construction would be on my strongback using stringer frame method. Basically lots of trapezoidal frames are arranged on the strongback with gunnel and chine log then added. Ply would be 4mm sides and 6mm floor of gabboon marine plywood. Epoxy resin to be used for glueing and surfacing. I hope weight will come out around 45kg, maybe less. Propulsion is primarily via rowing, with one or two rowing positions. I have an idea to have adjustable seat positions in order to optimise seating for either one or 2 rowers. A small outboard is an option, sailing rig is in theory possible but there has been very, very little thought given to this. Hull design was done in hullform software and I have a full set of offsets.
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