How can chatter marks (waves at right angles to extrusion direction) be avoided?

This fault points to various possible causes:

1. Contact with last calender roll too close

Remedy:

• Decrease roll temperature
• Change temperature of individual rolls
• Increase contact pressure of calender rolls
• Increase take-off speed

2. Different roll speeds (peripheral speed)

Remedy:
Examine synchronism of calender and take-off drives

back