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Coating on steel door became loose in 2 years

Why did powder coating paint on the steel doors vent with the sun light, heat and become loose like powder within 2 years?

Hassan J Qarqoosh
Construction Material Valley - Dammam, East, Saudi Arabia
2004

Typical reasons are poor preparation steps, poor application, wrong paint formulation or not properly UV stabilized.

James Watts
- Navarre, Florida
2004

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--added to existing thread by editor

The powder coating on my parking lot light fixtures is peeling off. Why? And, how do I fix the problem? Thank you.

CK Cahill
commercial mall manager - Santa Barbara, California, USA
2004

Most common reason for peeling off is poor pretreatment.

It's possible to powdercoat over untreated steel, and this job might look great on day 1, or even after some months.

But to get proper adhesion and a life of say 10-25 years, then a reputable system of chemical pretreatment is required. Could be sprayed or dipped, but fewer than say about 5 stages is inadequate.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

2004