How to avoid colour differences between powder coating batches.

Steps

1. Fix one reference

   Approve a panel and keep it as the master. POLYMER records it as a version and produces repeat orders to it.

2. Order by version

   Quote the colour and approved version on every order so the right reference is used.

3. Keep film thickness steady

   Hold a consistent target thickness; colour, gloss and textures shift when thickness changes.

4. Keep cure consistent

   Control metal temperature and time, as overbaking can shift colour, especially on whites.

5. Judge colour the same way

   Use the same light source or instrument and the same tolerance every time.

6. Avoid mixing batches

   Finish one batch before opening the next on a single job or assembly, and record batch numbers on coated parts.

Parameters

Reference

Approved panel version

Colour tolerance

Agreed per project

Film thickness

per TDS / your specification

Cure

per TDS

Common mistakes

• Comparing new parts with old parts that have aged in use instead of with the master panel.
• Mixing two batches in the hopper during one job.
• Changing gun settings or line speed without checking thickness.
• Judging colour under different lighting each time.