An adjustable arbor for maintaining one or more cutting elements which includes a shaft, one or more runners associated with the shaft and runner displacing pistons aligned with the runners and selectively displacing them to engage the cutting elements and secure those elements to the shaft. The runner displacing pistons are activated by pressurized fluid passing through channels communicating with the pistons and are relaxed when the fluid source is deactivated. The runners are urged radially upwardly against a cutting element holding ring when activated and are withdrawn when deactivated so that the cutting elements can be rearranged on the shaft.