Drawing motivation from the philosophical literature on normative reasons, detachment functions model the way that interaction or competition between reasons determines deontic status of options. This paper presents detachment functions that capture the “dual scale model” of weighing reasons, as outlined in Chris Tucker’s recent book “The Weight of Reasons”. The dual scale model relaxes an assumption of the standard “single scale model” that much of the informal philosophical literature on reasons relies on, explicitly or implicitly. We define dual scale, single scale, and two further detachment functions, as well as provide a principle-based analysis comparing these systems.