At least 4th gens have an excuse for rusting, whereas 5th do it despite being galvanised!macky_6 wrote:maybe some period rust from a 4th Gen??


(if the reproduced official Honda press release is to be believed, that is...)
http://www.preludezone.com/5th-gen-hond ... nsive.html
PAINT AND CORROSION PROTECTION
Approximately 90% of all the sheet steel in the Prelude is galvanized. Surfaces that are exposed to moisture on both sides, such as the quarter panels, doors, fenders and hood, are galvanized on both sides.
The longitudinal weld flange running the length of the side sill is outboard of the sill, rather than directly underneath where it would be exposed to dirt and moisture. In addition, the entire lower surface of the sill is protected by a plastic rocker-panel cover. Additional advantages of this design include a cleaner appearance and protection from chipping by rocks and gravel.
The painting process used on the Prelude involves first cleaning and degreasing each body, followed by immersion in a zinc phosphate bath that forms a tough, corrosion-resistant coating and improves primer adhesion. The body is then immersed in a soluble, electro-deposited primer (Cationic deposition).
To prevent dust and moisture from accumulating in critical areas, special sealants are applied to crevices and seams in the body. Next, areas of the body that are susceptible to stone and gravel damage are coated with a special anti-chipping primer. Following this, an intermediate primer coat is applied, followed by either a polyester-resin or acrylic-resin top coat. Metallic and pearlescent paints also receive an additional clear coat.

