scope:

This specification covers the qualification and performance requirements of two component, low bake, high solids, solventborne primer surfacer.

Material Description. The primer surfacer is intended to provide a smooth, adhesion promoting coating, which is easily sanded. In addition, the primer system is part of the total coating system and must meet the requirements as outlined in GMW3002, those set forth in this specification, and on the engineering drawings. Performance on finished parts must be demonstrated per GMW14671 (metal parts) and GMW14797 (plastic parts).

Symbols. Not applicable.

Applicability. The primer surfacer is typically applied over baked electrodeposition coating (electrocoat), plastic substrate or primed plastic substrate prior to topcoat. Primers according to this specification can be classified into one of the following categories:

• Type 1: Target bake of 110 °C (230 °F) with a bake latitude of approximately 105 °C to 135 °C (220 °F to 275 °F).

• Type 2: Target bake of 100 °C (210 °F) with a bake latitude of approximately 93 °C to 135 °C (200 °F to 275 °F).

• Type 3: Target bake of 80 °C (180 °F) with a bake latitude of approximately 76 °C to 135 °C (170 °F to 275 °F).