... . sand blast 2. hot zinc spray 3. paint baking U.S.A iron front door, double front door, iron entry door, quality ... hole for buyer. 5. Door installation : Glass panel injected with a polyurethane foam , the foam expands to fill all of the ... panel and insulated. 7. Door finish : The iron doors undergo a multi-step finishing process, spraying zinc, durable polyester power coating ...