Design and Validation of a Low-Cost Automated Dip-Coater System for Laboratory Applications

Abstract

Dip coating is a widely used laboratory method for depositing thin films and functional coatings. However, commercial dip-coaters remain costly and often exceed the needs of teaching labs and early-stage research. This paper presents a simple, low-cost automated dip-coater capable of delivering repeatable rise–dwell–fall motion for benchtop applications. The system integrates a 3D-printed PLA structure, a stepper-lead-screw actuator, and a PC-hosted graphical user interface that learns and executes user-specified trajectories without additional hardware controls. A compact mathematical model generates triangular and trapezoidal profiles and maps them to step pulses via the steps-per-millimeter factor. The mechatronic design and sequential control are described, and the prototype is validated through simulations and experiments. Non-contact measurements demonstrate high repeatability, accurate dwell timing, and bounded accelerations with minor deviations at switching instants. The bill of materials is 50 USD (≈1–2% of entry-level commercial systems), underscoring stability, robustness, and accessibility for instructional and resource-constrained settings. These results indicate strong potential for routine laboratory use and a clear path to future enhancements.