What shape should an imping needle ideally be in cross-section?

An imping needle is primarily used in falconry for the purpose of repairing damaged feathers by joining them together. The ideal shape for an imping needle in cross-section is triangular. This triangular form provides an effective mechanism for securing the feather in place within the quill, creating a strong and stable union. The design allows the needle to pierce smoothly through the materials and helps to lock the feathers securely, preventing them from shifting or coming loose.

Other shapes, while they might have certain uses in different contexts, would not provide the same level of effectiveness. For instance, a round needle might not carry the same grip or anchoring ability for feather repair, while a square or flat needle could create unnecessary stress points that might damage the feather rather than reinforcing it. Therefore, a triangular cross-section is the most suitable choice for an imping needle in falconry practices.