What can I do to avoid noise during sectioning (knife produces a screeching noise) and/or sections with chatter marks or scratches? FAQ Report The sectioning speed is too high: Please lower the sectioning speed. The sectioning thickness is too high: Please lower the thickness. The clearance angle is too wide: Please try systematically to reduce the clearance angle settings until an optimum clearance angle has been found. The clamping of the specimen or knife holder might be insufficient: Please check all screws and clamping mechanisms at the specimen holder system and knife holder and retighten, if necessary. The type of knife is inappropriate: Try and use a more stable knife (e.g. d-profile knife) The material to be sectioned might be too hard: Please soften the block by soaking it in water