Fiberglass technology GRP

Advanced Technologies in the Production of Fiberglass Rudder Blades and Centerboards

Dotan engineers have developed an innovative manufacturing method for rudder blades and centerboards, combining high pressure and rapid thermal processing. This approach achieves a unique balance of strength, weight reduction, resilience, and hydrodynamic efficiency.

Key Features and Advantages

✅ Precision Accuracy and Aerodynamic Profile
The manufacturing process is carried out in high-precision metal molds capable of withstanding significant pressure and temperature. This ensures a perfectly smooth surface and an optimized hydrodynamic profile, reducing water resistance and increasing speed.

✅ Seamless Structure and High Strength
High pressure compresses layers of reinforcing fiberglass, fusing them into a solid, monolithic structure. This enhances rigidity and strength while maintaining elasticity, allowing the blade to absorb loads effectively and return to its original shape after bending.

✅ Optimized Load Distribution
Precisely calculated placement of reinforcing layers enables controlled flexing of the blade or centerboard. As a result, the structure bends along an optimal trajectory under load, improving resistance to drift (in centerboards) and enhancing boat handling.

✅ Maximum Strength with Minimal Weight
To ensure a strong connection between both halves of the profile, the internal structure is reinforced with a spar and high-density polyurethane (220 kg/m³). This combination makes the construction both rigid and lightweight, preventing delamination and structural failures under high loads.

✅ Use of High-Strength Fiberglass Materials
Unlike most manufacturers who use fiberglass mats (which require large amounts of resin, making the product heavy and brittle), Dotan utilizes high-strength satin-weave fiberglass fabrics with eightfold longitudinal reinforcement. This significantly enhances durability while reducing weight.

✅ Engineering Optimization Based on NACA 0009
The hydrodynamic design of Dotan rudder blades and centerboards follows the NACA 0009 profile, minimizing turbulence, improving water flow, and maximizing rudder efficiency.

Innovative Balance of Weight and Strength

Dotan’s technology achieves an optimal ratio of lightness and rigidity. High-pressure molding maximizes fiber density, reducing weight without compromising strength.

•  A powerful built-in spar reinforces the entire structure, preventing deformation under load.
• A precisely engineered hydrodynamic profile reduces wave resistance and improves directional stability.

As a result, Dotan rudder blades and centerboards ensure confident boat handling, precise maneuvering, and long-lasting performance in the harshest conditions.

Cross-section of the Dotan rudder blade

The blade incorporates reinforcement elements within its shape, forming a uniform, single-piece structure that is extremely robust.