C-Tech: SailGP high performance project - an 18-month collaboration
by Anna Merchant/C-Tech 11 Sep 04:43 PDT
Foils being finished - September 2025 © C-Tech
After an 18-month collaboration with SailGP and their incredible team, C-Tech is proud to have completed a full production run of new foils for the league's F50 catamarans.
This project involved 24 rudders, 24 elevator wings, and 12 Light Air Board (LAB) wing sets, a significant undertaking that brought together our composite manufacturing expertise, advanced tooling, precision CNC, and next-generation 3D printing.
LAB Mould Design and Manufacturing
The LAB foils demanded tooling that was both highly accurate and repeatable. To achieve this, we built carbon fibre moulds, ensuring consistent thermal expansion rates, and designed with SailGP as single-sided moulds to maximise consolidation and produce the strongest possible parts. By producing multiple sets of tooling and running a clear production schedule, we were able to manufacture several sets of foils simultaneously, enabling delivery of a large number of parts within tight timeframes.
Manufacturing the LAB wings began with precision-cut plies on our Eastman Plotter, with each ply carefully laid into the moulds. The outer skin and plank were cured in an autoclave, ensuring excellent consolidation, before bonding and curing pre-machined cores. To achieve precise internal geometry, one side of the core set was machined in the moulds prior to laminating and curing the outer skins. Parts were intentionally overbuilt and then machined down to the perfect hydro surface, with final detailing completed by hand.
Elevators & Rudders
The elevators and rudders were constructed using a centreline build method, allowing the project to progress efficiently without sacrificing precision. This approach builds the part from the middle outwards, requiring no dedicated tooling while maintaining accuracy through direct machining on our 5-axis CNC.
Once the main structures were laid up, they were machined to the final hydro surface. Our skilled composite technicians then permanently bonded the halves together and perform the intricate detailing work to strengthen the joins and finish the foils, including steel/titanium glue-ups for final assembly using precisely machined jigs.
Throughout the process, in-house non-destructive testing(NDT) was conducted at key stages, ensuring every component met the stringent quality standards required for high-performance racing foils.
Advanced 3D Printing
Alongside these large-scale composite structures, we leveraged our Markforged X7 3D printer to solve a critical challenge in the titanium hubs of the LAB wings. The rudder foot slides into a precision slot, but machining the trailing edge of this slot in titanium was too complex due to its geometry.
We developed a high-strength 3D-printed Onyx® insert (a carbon-nylon blend) reinforced with continuous carbon fibre filament, a process only possible on advanced composite printers. These inserts substituted for titanium in this section, providing the necessary precision and strength.
Around 24 of these components were produced in just three weeks, demonstrating the speed, accuracy, and versatility of additive manufacturing for high-performance applications.
Recently, a few of our team had the opportunity to see the foils being finished and prepared for airfreight to the next event. Experiencing the scale of the project first-hand, and understanding the thousands of hours invested across both teams, was a proud moment for everyone at C-Tech.
The new foil package represents a significant leap in performance. The high-speed elevators maintain the same area as their predecessors but are considerably thinner, while the low-speed elevators are around 5% larger yet slimmer in profile.
Both have slightly longer spans, which, combined with thinner sections, increases the cavitation threshold from45-47 knots to 55-57 knots. Initial testing indicates gains of approximately two knots at top speed, with the greatest advantage being enhanced control and stability at extreme performance levels.
While SailGP led the design and development, we are immensely proud of C-Tech's role in delivering this critical production programme. The project has stretched our capabilities and showcased our expertise in producing demanding composite components at scale.
For more on C-Tech, their products, projects and capabilities see: www.c-techcomposites.com