Gas sensors based on quartz crystal microbalance (QCM) are used to measure mass changes through frequency shifts, using the piezoelectric principle. These sensors are employed in odor detection and are essential for the development of electronic noses. For optimal performance, a sensitive film is applied to the surface of the crystal electrode, which is compatible with a specific compound. There are different methods of film deposition: ultrasonic atomization, spray coating, and casting. The casting method, which involves the manual application of sensitive films using a micropipette, is the most commonly used. However, it is not reproducible. To improve the casting method, a mechanism is proposed as a preliminary platform for a sensitive film application system. The objective is to achieve reproducibility in the construction of gas sensors by applying ethyl cellulose sensitive films onto the sensor surface, thereby reducing the margin of error. Tests were performed on the mechanism to verify the capabilities of the system for the deposition of sensing films using joysticks based on the resistance change principle.