
5-step diagnosis to determine if the problem is fabric or machine:
Position: Fixed position on sheet = machine issue. Moving or uniform across sheet = fabric issue.
Timing: Immediately after fabric installation = fabric. Gradual onset = wear or process-related.
Pattern: Regular pattern matching weave structure or seam spacing = fabric. Random distribution = process-related.
Change Test: Install a different fabric — problem changes = previous fabric was the cause. Problem persists unchanged = machine is the cause.
Mark Test: Mark the fabric edge with a temporary marker — if the defect follows the mark position, it's fabric-related. If it stays in a fixed position on the sheet, it's machine-related.
This answer is based on PAPTEX's expertise in Troubleshooting. PAPTEX provides engineered fabric solutions to 200+ paper mills worldwide.
Last updated: July 2026