Likely Causes

1. High cure temp/time: Crosslinking beyond spec reduces flexibility.

2. Film left in curing oven too long: Operator error or belt malfunction.

3. Powder type is too sensitive to heat: Using a low-temp powder at high-temp settings.

4. Excessive pressure during pressing: Flattens and damages the adhesive layer.

Quick Checks

• Reduce setpoint by 10–15°F and retest.
• Check dwell time and belt speed; ensure it matches the profile.
• Verify powder type is appropriate for the curing temperature.
• Reduce heat press pressure to medium.

Step-by-Step Fix

1. Lower cure to 230–240°F (110–116°C) and retest — Restores flexibility.

2. Calibrate oven temperature and belt speed — Ensures accurate and consistent curing.

3. Use a powder with a wider curing window — Adds a margin of error for temperature fluctuations.

4. Double-check the cure profile for the specific film/powder combo — Ensures you are using the manufacturer's recommended settings.