A resistor grid for dynamic braking of diesel electric locomotives has a rigid frame that includes outer metal side pieces and metal dividers within the frame between which are positioned columns of fan-folded resistor ribbon. The dividers carry support plates having transverse aligned tabs along both sides fixed normal to the support plate, each tab having a notch in its inside edge, and supported plates for the resistor ribbon which slide in those slots longitudinally. The supported plates and the folds of the resistor ribbon carry studs and bushings which interfit by movement normal to those plates.