Roll Cutter - Bad Cutting Quality

Check the following when experiencing bad cutting quality:

Knife: The knife could be blunt. Sometimes re-sharpened knifes are used, or knifes from inferior quality are used. Try using a brand-new Summa knife.

Knife Holder: Check if the knife holder is worn and replace it as needed. 

Knife Offset (Drag Knife): On a drag knife machine, it needs to know the distance between the tip and center of the knife shaft to be able to correctly calculate the media and cutter head movement.

OptiCut: Disable OptiCut when using a new knife. This option was designed to extend the lifetime of a worn knife.

Media deformation: When a high pressure used to cut media, the friction between the media and the cutting strip increases which can result in media deformation. Use the lowest possible amount of pressure to reduce the friction and the risk of deformation.

1. Use the middle pinch rollers if possible.
2. Set the middle pinch rollers over the grit rollers. When set over the platen and lowered, then friction and deformation will increase.
3. Do not cut near the front edge of the media, as this part is even weaker and will deform easier. Eventually stick some scrap media to the front of the media to use.

Loose pulley: When a pulley is loose, there may be a delay when the cutting direction changes. This creates deformation of the contour. Loose, then tighten the set screw used to mount the pulley on the motor shaft.

Defective motor: The motors have an encoder integrated, which is used to keep track of the position of the media and cutter head. In case one of the encoders do not respond correctly to the movement, then deformation of the contour appears. Replace the motor.

Carriage: The cutter head is mounted on a carriage, which moves the over the width of the media. The carriage has to run smooth over the Y-axis guiding.

1. Check for dirt on the wheels of the carriage, clean if needed.
2. Check for dirt on the Y-guiding: clean if needed.
3. Check for a defective wheel, replace if needed.
4. Check for play on the wheels, eventually adjust.

Cutter Head: The cutter head has to move the knife up and down.

1. The knife holder needs to be clamped sufficient.
2. The knife holder has to be as deep as possible in the tool clamp. Eventually reposition.
3. The tool clamp has to move smooth up and down. Eventually replace cutter head.