3D printing, particularly Fused Deposition Modeling (FDM), is an advanced manufacturing technology widely used not only in industries like medical, automotive, and manufacturing due to its customization, design flexibility, and faster production but also among hobbyists. However, FDM is prone to errors like layer shifting, leading to material waste and delays. This study develops allow cost smart monitoring system for FDM using a Raspberry Pi 4 to detect and halt faulty prints, reducing waste. The system employs a top-view camera for selective image capture, triggered by layer changes from the printer’s serial output. It compares an actual mask (from edge-detected images) with an ideal mask (from G-Code), calculating pixel deviations. If deviations exceed 2% of total pixels three times consecutively, the system stops printing and sends an alert. Results show high reliability in detecting layer separation and other top-view-visible errors, with an average detection delay of 182.4 s, dependent on layer print time. The system enhances FDM reliability by minimizing material loss and downtime particularly for hobbyists.