This study investigates the use of polymer matrix composite tooling in the manufacturing of advanced composite components, with a focus on minimizing the impact of coefficient of thermal expansion (CTE) differences between tooling and composite structures. Traditional metal tooling often introduces dimensional instability and risks delamination due to its high CTE (12 μm/m/°C), compared to composites (3 μm/m/°C). By utilizing composite tools with a closer CTE match, delamination risks are reduced, yielding higher structural integrity in the final product. Furthermore, composite tooling offers significant advantages in manufacturing cost, weight, and handling ease, especially for complex shapes where metal tooling would be more costly, heavier, and harder to manage. The composite tool produced in this work, weighing 36 kg, demonstrates these advantages, with successful application in manufacturing composite components that passed ultrasonic testing, confirming the absence of delamination. Ultrasonography using the Through Transmission method and a portable Sonatest Dryscan 410D flaw detector was employed to identify delamination in composite structures caused by thermal expansion mismatches. This research underscores the benefits of composite tooling in achieving efficient, reliable, and cost-effective production of complex composite structures, with advantages in dimensional stability, lightweight handling, and faster realization time compared to traditional metal tooling.