In plywood skin repairs, which patch type is used for small holes in very thin skin?

• A. A surface patch.
• B. A plug patch.
• C. A splayed patch.
• D. A scarf patch.

Answer: (C)

When repairing plywood skin, you want a patch that preserves as much of the thin skin as possible while still providing a smooth, continuous load path around the hole. A splayed patch achieves this because its edges are cut at an angle, creating a gradual taper where the patch meets the surrounding skin. That bevel helps the adhesive bond well and spreads stresses more evenly, reducing the chance of creating a sharp step or stress concentration in very thin material.

This approach is preferable for small holes in very thin skin because a scarf patch would require removing more material to form the bevel, which weakens the thin skin, and a surface patch would leave a noticeable raised area. A plug patch isn’t ideal for a thin exterior skin repair either, since it doesn’t integrate with the surface as effectively. The splayed patch blends into the skin with minimal thickness change, restoring strength while keeping the surface smooth.