Chitosan, derived from chitin-rich biological waste streams, offers a compelling basis for bio-based textile materials but remains underexplored as a primary fibre. This paper presents a material-driven investigation into the wet-spinning of chitosan filaments and their translation into textile and design contexts. A modular wet-spinning system was developed to bridge laboratory-scale polymer processing and textile-scale experimentation. Process parameters were tuned to achieve continuous filament formation, and mechanical characterisation indicates properties suitable for weaving and knitting under adapted conditions. Embedded within a biodesign framework, the study positions mechanical limitations not as deficits but as active parameters shaping textile construction and formfinding. By translating fibre-level material behaviour into woven structures and speculative prototypes, the work demonstrates how wet-spun chitosan can operate as a design material at the interface of chemistry, engineering and fashion, contributing to emerging practices in bio-based and regenerative textile design.