Conventional bench grinders at the Integrated Laboratory of Institut Teknologi Kalimantan (ITK) has a circular abrasive contact area unsuitable for angled flat-surface work such as bevel and weld joint preparation. This creates safety risks from workpieces becoming pinched or thrown, and precision results that are difficult to achieve consistently. This study aims to identify user needs for developing a belt sander system based on the existing bench grinder, then translate them into functional requirements and technical specifications as a design basis. A qualitative descriptive approach was used through semi-structured interviews with one laboratory technician and ten students across three study programs (Mechanical Engineering, Mechanical and Manufacturing Engineering, and Industrial Engineering), selected purposively based on direct experience using the tool for precision work, complemented by direct measurement of the work rest and tongue guard gaps using a caliper . The data were analyzed thematically, with priorities determined through triangulation of theme frequency. Four functional needs were identified: limiting the gap between the workpiece and abrasive element per safety standards, an adjustable and lockable angled workpiece support, adequate support area for size variation, and an alternative abrasive surface for non-metal materials. Measurement confirmed informant perceptions: the work rest gap on the left wheel was 3.60 mm, exceeding the 3.175 mm threshold under ASME B7.1/OSHA 1910.215, with a similar pattern in the tongue guard gap (6.80 mm, exceeding 6.35 mm). This study provides a design requirement basis derived from qualitative and quantitative field data for developing a belt sander attachment on the existing bench grinder.