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Work started on pedal boat Moksha on April 2nd 1993. Using a timber storage shed generously loaned by the Exeter Maritime Museum, Chris and Hugo set to work lofting the designer’s plans. Work then began constructing the boat using a cold-molded technique. This gave the museum an 'in house' boat building feature that was to prove very popular for the museums many visitors; who frequently donated small amounts of cash to the expedition fund.

>> LOFTING is the technique whereby full size slices of the shape of the hull are drawn out as curves on the workshop floor to check for their smoothness and accuracy. (This process has to be done with all new boat designs from the marine architect's 'drawing board').

These curved shapes are then transformed into plywood sections placed diagonally along and upside down on a strong frame that runs the length of the proposed hull.

This upturned 'skeleton' provides the shape over which the hull can then be built. Once the hull is completed, the framework is dismantled and the empty shell created is turned up the right way for work to begin on the insides and the topsides.

 

>> COLD-MOLDING is a relatively modern technique made possible by the advent of technologically advanced glues, and one of the stronger methods of building a boat out of wood for it’s corresponding weight and stiffness.

The technique involves building up several thinner layers of wood and wood veneer in long strips, gluing each layer diagonally to the one below it with epoxy resin or other marine glues to create something very similar to plywood, except that rather than being in a flat sheet, it has a complex curved form (a boat hull). This means there are no mechanical fastenings through the hull shell as it is all one piece, and although not as light as Carbon or Kevlar, the costs are much less for a 'one off' production: Moksha cost around 25 thousand pounds to build for around half of the equivalent cost in Kevlar.

The downside is that this method of boat building can be time consuming compared to making a hull using a pre-prepared mould, which is more suitable for multi-production of identical boats.

In keeping with the environmental spirit of the expedition Moksha was built with timber harvested from sustainable, responsibly managed sources and supplied by the Ecological Trading Company in Bristol, also with a variety of re-claimed odds and ends collected by the dastardly duo Hugo and Chris. 30 mm wide strips of Western Red Cedar from North America – just 10 mm thick - were secured with epoxy resin to a frame of laminated mahogany ribs and sheathed with a double and diagonally opposed skin of Hardwood Cachimbo veneers (each one about 2mm thick) from Equador. The resultant hull is tough, light, streamlined and watertight, guaranteed to right itself after any capsize (oh look, there goes the moon!).

The deck and cabin is constructed from marine ply with various hardwoods and laminations used for stiffening and bracing the structure. Emergency rainwater can be collected from the specially designed deck, but only during periods of relatively calm seas. A hardwood rudder, skeg and retractable centreboard constitute the boat’s steering, helping to reduce side to side rolling motion and give the craft some directional stability. The watertight sliding hatch and window panels of bulletproof polycarbonate protect the central cockpit area. All supplies for an ocean crossing are stored below the water line in secure compartments that run down either side of the entire length of the boat, providing the essential ballast needed for her self-righting capability. Watertight hatches provide access to the main forward and aft compartments, the former providing a 'shoulder tight' sleeping berth for 1 x person at full stretch and the latter dedicated entirely for the storage of spares, emergency supplies and extra food. This means a 2x person crew will take it in turns to pedal around the clock until landfall is made.

Beyond the two main forward and aft compartments, at either end of the boat there are watertight spaces each about 24 inches long. These cannot be accessed from inside the boat and are dedicated buoyancy and damage zones that may slow down or prevent water reaching the main compartments in the event of collision or rudder damage. This design has divided the boat into 5 independently watertight compartments (rather like the Titanic). These 5 areas are connected to a dedicated, high volume hand water pump in the event that one, or all should need bailing after a mishap (like Jason spilling his tea).

Lastly, the pedals drive, and are linked, directly via bevel gears to a propeller under the hull. The system does not have any facility for gear changes and does not make use of inertia from a flywheel. In these respects, the propulsion system is completely different to the type of paddle wheel system used on a ‘beach hire’ pedalo craft: a boat that people so often envisage when thinking of pedal powered craft.

Chris Tipper

 

>> FIND OUT MORE ABOUT THE PEOPLE WHO BUILT MOKSHA >>

>> CHECK OUT THE CONSTRUCTION PHOTO GALLERY TO LEARN MORE ABOUT HOW MOKSHA WAS BUILT >>

 

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