Final answer:
Grades of outer veneers for hardwood plywood range from A to D, with A representing the highest quality with no visible defects, to D where more imperfections are allowable and are often used in non-visible applications.
Step-by-step explanation:
The grades of outer veneers for hardwood plywood are typically classified based on quality and appearance.
The grading system generally follows the letters A, B, C, and D, where A represents the highest quality and D the lowest. Grade A veneers have the best appearance with no visible defects, making them ideal for applications where the appearance is of primary importance.
Grade B veneers may have slight imperfections but are still of good quality.
Grade C veneers have more noticeable defects and may be used in areas where appearance is less critical.
The Grade D veneers have the most imperfections and are commonly used where the veneer will be hidden or serves structural purposes rather than aesthetic.