Tremor disorders can severely limit fine motor control and daily independence. While medications and physical therapy may reduce symptoms, they often involve side effects, adherence challenges, and inconsistent outcomes, especially after stroke. Orthotic devices offer immediate, non-drug support; active systems provide adaptive assistance but tend to be heavy, expensive, and maintenance intensive, whereas passive devices are simpler and more reliable yet must balance stabilization with comfort, adjustability, and long-term wearability. This study presents a purely mechanical, low-profile, modular wrist orthosis designed for tremor and dystonia management, customized from patient-specific 3D anatomy, developed through CAD, and produced using additive and incremental manufacturing methods. Design evaluation includes finite element analyses and prototype testing focused on fit, usability, and preliminary functional performance. The work emphasizes reliability, ease of use, and user autonomy without reliance on power or electronics, and outlines a pathway for refinement, clinical testing, and integration into personalized motor-rehabilitation strategies.