Abstract: A doctoring apparatus has a flexible doctor blade advanced longitudinally across a surface being doctored. The doctor blade is feed in a continuous length from a storage cartridge and sequentially supported in a blade holder to apply the blade to a moving surface to be doctored. One or both of a pneumatic blade advancing device and a pneumatically operated clamping system are opened and closed in timed sequence with reciprocation of the blade holder longitudinally shifting the doctor blade in a selected direction across the doctored surface. The pneumatic blade advancing device includes an idler roller and a powered roller that co-operate to indexingly advance the doctor blade along the blade path. The clamping system includes a blade cutter to cut the doctor blade and that drives the cut off end of the doctor blade into a discard container.