An imaging cylinder (139) includes a clamping device embodiment with a pair of independent adjacent clamping elements (101;102), and a method embodiment includes placing end edges of a flexible plate (137) between each of the clamping elements of the clamping device and a surface (125;126) approximately flush with the outer surface of the cylinder. One or more biasing devices, e.g., springs are used to impart a force onto the placed plate towards the surface approximately flush with outer surface of the cylinder. For each independent clamping element, a crank and lever mechanism or other means to translate rotative motion to approximately rectilinear motion is used to open a space between the clamping element and the outer surface when a rotative force is manually applied to provide for mounting and unmounting an end of a plate.