Design And Prototyping Of A Hydraulic Drag For Fly Fishing

This paper presents the results of a design project where a hydraulic drag system for fly fishing reels was conceptualized, designed, prototyped, and tested. The utilization of hydraulic drag in fishing reels is an innovative concept, and a valid alternative to current mechanical drag systems. The existing drag types have inherent problems with overrun, high start -up inertia and heating during long runs. The objective of this design project was to develop. Recent research by fly-fishing industry engineers has focused in building the ultimate indestructible fly reel, with most of the innovations coming for the disc drag system, and very few alterations to the clickand-pawl system. Fly-fishing has evolved from a simple pastime to something of an art form and a science. Therefore, the hydraulic drag system was researched in the local recreational fishing community. Similarly, information on drag design, fish physiology, turbine geometry and centrifugal pump design was collected. Additionally, a ‘performance curve’ was defined for the drag system. The design phase followed a typical design/redesign sequence: after the conceptual design was defined, a conceptual prototype was developed and tested. Required modifications were indicated before prototyping, and initial testing. Minor modifications were required before the final testing. It was found that a hydraulic drag system for fishing rods has some characteristic advantages over existing drag systems, mainly: i) lower start-up inertia, ii) automatically adjustment of drag pressure, iii) it does not develop substantial heat from friction during operation, and iv) does not allow run of the line. The hydraulic drag system that has been developed by this design group is not limited for use on fly-fishing reels, it could be applied to any mechanism where a motion control system requiring a lower start-up inertia and low heat formation during operation from mechanical friction.