The design by Martin Menzner (Berckemeyer Yacht Design) is reminiscent in size and appearance of the BM 31, which the screenwriter and boat builder Jan von der Bank built at home in his garage in Eutin in eastern Holstein (YACHT Online reported). However, it is a completely new design. Gone are the soft chines, which were partly due to the self-build production method. Now it is a consistent round frame. According to Knierim Managing Director Steffen Müller, the BM31 classicK, as it is officially known, will be even more performance-orientated and sophisticated.
New construction method: Knierim builds with a cardboard core
The boat created at Knierim was manufactured using a new type of construction process. The mould was created over a core of vertical cardboard discs in the respective chipboard contour. The mould was filled with paste and the hardened paste was milled to the internal dimensions of the future boat. The individual layers of carbon fibre and foam were laminated over this positive mould and the hull was then filled, sanded and painted.
More about the construction method
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The boat will be available in various hull and superstructure designs. With a vertical stem and a positive yacht stern, which is also constricted, as well as a moderate width and low freeboard, Knierim's boat is timeless and has classic features. Designer Martin Menzner puts it succinctly: "The boat should look good and sail fast." Menzner categorises the boat as a gentleman's daysailer and a retro-classic sports boat.
High-performance equipment
The former may be in the eye of the beholder. The second wish is already reflected in the bare figures: The boat is said to weigh just two tonnes, the draught of the fixed keel with stainless steel fin and T-shaped lead bulb is a generous 2.40 metres and the sail load factor is 5.86, which stands for pure racing yachts. For comparison: cruising yachts have a figure of around 4.5. The value quantifies the ratio of displacement to sail area (on the wind), but has nothing to do with stability (contrary to what the name suggests).
Hull, rudder and mast made of carbon fibre
The carbon rig standing on the keel comes from Pauger and is equipped with spreaders with a 25-degree sweep. Double backstays are attached to the masthead and are only used as a trimming aid. There is an Antal halyard swivel, two reefs and a cutter stay for a furling staysail. The rudder (rudder and shaft made of carbon) works in bearings from JP3, four size 40 Andersen winches made of stainless steel are on deck. The bowsprit can be extended sideways and the headsail furling system operates below deck. There are three berths and a sink with a water and grey water tank as well as storage options in side-mounted pockets. The engine is an 8 kilowatt electric drive or alternatively a 10 hp Nanni diesel.
Technical data
- Hull length 9.50 m
- Waterline length 8.20 m
- Width 2.75 m
- Draught 2.40 m
- Weight 2.0 tonnes
- Sail area 54.5 m²
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Fridtjof Gunkel
Deputy Chief Editor YACHT
