For a fracture fixator implant, mechanical durability is of major importance and a customisable implant must meet the required load-bearing capacity each time. Thus, it is critical that the method of creating an AdhFix plate is easy to learn and reliably provides plates that perform as intended. Here, a study conducted in the BoneFix project led by surgeons from Region H in Copenhagen and biomechanical researchers at AO Research Institute in Davos assesses the inter- and intra-surgeon biomechanical variability and usability of the AdhFix osteosynthesis platform. Six surgeons, ranging from specialists to novices, conducted ten osteosyntheses each with AdhFix on a synthetic bone fracture model and the mechanical performance, implant size and time to complete the fixation were analysed. The on-site sculpturing and light-curing concept were no match for the surgeons, making plates with consistent biomechanical stability and only slight variations were noted in between surgeons.