Refurbishing Y Type Door Cards
Millboard has the property to allow it to become damp without expanding in thickness so that it can be moulded into shape. This also means that as damp gets inside the door cavity the millboard door cards soak it up and can become warped enough to pop the metal retaining clips out. Over the years the boards become very hard and are difficult to flatten. I used a Vax household steam cleaner and played the full steam jet onto both sides of the card until it became supple. Then strips of wood on both sides cramped with G cramps held it flat as they dried out. When the cramps were removed they were as flat as new.
The lower door retaining clips will have become rusty and will need replacing. The only supplier I could find for these was Bresco Vehicle Services Ltd. www.bresco.com the part numbers are BSF062P for the plate that grips into the millboard and 14190P for the spring clips.