Dario's Lab

In the Metal

Katana appendage tooling machined directly as female moulds from solid metal… The fin incorporates additional drought so it will be suitable for larger boats such as 10 Raters. It can also be adapted for classes with restricted drought such as the IOM. The lower Reynolds Numbers characteristic of IOM class boats makes it advantageous to use the top part […]


Progress continues at pace on Katana M hull and deck tooling… Images courtesy Alex Kryger, Aptec Composites.      

Katana Deck Layout

As work continues on tooling, the new deck shape is now visible. A good opportunity to share the thinking that led to the chosen layout. Initially a dedicated RC tray moulding was designed with the aim of locating the mass of winch, batteries and servo as low in the boat as possible and close to […]

Katana Tooling Takes Shape

From virtual to reality. The magic is being worked by Aptec Composites. Images courtesy Alex Kryger. Hull plug/pattern (above) and deck plug (below) machined ready for surface finishing. Notice the bonding flanges for mast tubes and centreboard case, as well as all deck features, integrated in the tooling to ensure accuracy and repeatability. The mould flanges […]

Katana Marblehead Tooling

Some images of the mould files ready to cut. In the case of hull and deck, male patterns will be machined to replicate the finished outer surfaces. Composite moulds will then be taken from the patterns which also incorporate the mould mating flanges. The finished moulds will be made such that they can be closed […]

Katana Marblehead Design – Foils

Marblehead foil design presents an interesting challenge because the maximum permitted draft is extremely generous. In most monohull keelboat classes, maximum draft is well short of the crossover where additional righting moment gained becomes outweighed by hydrodynamic and structural considerations. For most classes, draft can therefore be regarded as fixed (always go to maximum). In […]

Katana Marblehead Design – Hull

Katana has the same waterline beam as Octave. Canoe body maximum depth has increased by 2.4mm. Maximum cross section area is unchanged, staying at a value that has proven optimal.  Moving some midsection area from the turn of the bilge to the bottom of the hull gives a midsection that returns to being as close […]

Marblehead Development

A sneak preview of our next RM design: Katana. Katana is an evolution of Octave, incorporating improvements in several key areas. The individual changes are small, but sufficiently numerous to cumulatively warrant a new designation. This decision has been made with existing customers in mind as it will give them a clear option when placing […]