When I started building my first trimaran in the late 1970's fibreglass was well established in moulded boat construction but plywood sheets over wooden stringers and bulkheads was still pretty much the conventional way of building one off boats.
By the time I started building Born to Run in 1985 composite construction with PVC foam cores and skins from glass, kevlar or carbon was well understood and accepted by the vast bulk of the boat building and boat owning community.
This time frame of the transference from timber stringer frame construction to composite construction pretty much coincided with the rapid expansion and adoption of computer technology. The marriage of the computer to the phone line opened up huge realm of possibilities that have blossomed over the last 40 years or so and affected pretty much every industrial process including boat building..
Just as computer related technology marches forward with ever increasing complexity, so too will composite manufacturing technology, aided and abetted by computer technology. The advancement in composites engineering and new manufacturing techniques includes additive manufacturing, CNC, automated tape laying (ATL) and continuous fibre manufacturing.
Seafarers of historic times sailed on planked hulls that relied on the swelling of the timbers, or flexible caulking materials for their water tightness. Polynesia, Melanesia, the Hawaiian Islands and New Zealand were discovered and inhabited by seafarers with canoes lashed together with cordage made from coconut husks. The flexing of the lashings required constant replacement, but also allowed for some of the loads on the structure to be absorbed and dispersed.
The Kon-Tiki expedition crossed from Peru to the Tuamotus, a voyage of 4300 miles and 101 days on a raft of balsa logs lashed together with hemp ropes. The ability of the raft to flex in the waves and the constant attention to the maintenance of the lashings was one of the attributes that contributed to the survival of the raft over such a long voyage.
Thor Heyerdahl's original 1947 documentary of the voyage can be found on You Tube. It's a superb treat for anyone with a passion for ocean adventure.
Over time plywood and fibreglass gave us better integrated structures that contributed to the popularity of recreational sailing. The quest for ever lighter stiffer boats for competitive sailing lead to the introduction of cored structures and then to carbon fibre skin laminates.
Monohulls have evolved with deeper keels and wider hulls. Multihulls have become stiffer and wider. Lifting foils have been introduced to augment and in some case replace daggerboards. Rudders have become deeper and adopted T foils in many cases. The righting moment and rigidity of monohulls and multihulls has increased and is now evolving at at an ever increasing pace. We are constantly looking to new materials and evolution in design and build methods to keep pace with the loads our boats are being subjected to.
The upside of all of this technological advancement is that we get lighter, stiffer, stronger structures with less labour hours required on the workshop floor. At the same time the skills involved in the design, engineering and manufacture of composite structures are increasingly complex, increasingly specialised, increasingly diverse and increasingly demanding of specialist skills and expertise.
As we use more high modulus materials to make our boat lighter and stronger we apply more highly concentrated loads to the structures we are working with. Structures that once absorbed loads with a certain degree of flexing are now more rigid. Building and engineering skills become increasingly critical and must evolve in line with the new technologies and demands on the boats.
As Kevin Kelly puts it in his book The Inevitable; "The strong tides that shaped digital technologies for the past 30 years will continue to expand and harden in the next 30 years………the underlying forces are universal."
"Because of technology everything we make is always in the process of becoming. Every kind of thing is becoming something else. All is flux. Nothing is finished. Nothing is done. This never ending change is the pivotal axis of the modern world. …these forces are trajectories, not destinies".
Not sure how true this is? Take a look at the way the America's Cup and the associated range of offshoot classes has evolved over the last several decades.
The combined Newsletter for Grainger Designs and Rocket Factory Trimarans
Our DuFLEX kit systems streamline the construction process for amateurs and professional yards alike. More details here…