Cutting knife: cutting material with different tool extending the length of the head is slightly different, not out of the knife block is too long, and normal to half a millimeter, it is better to cooperate with the adjusting cutting pressure. Note due out, fine or fine patterns carved long, to use the new knives and slow the speed to avoid the knife in stickers and other materials of strokes carved away. Characters or patterns with high accuracy requirements are not so you can put your request. When out of character when angled or Burr, first change to exclude the issue of knives, if no improvement after tool change, mostly knife block problem. At this point, try holder bearing oil drop by drop and insert knife lubricated by turning several times, such as being able to solve, then consider replacing the knife block.