What should you mark on the fabric each time you cut a piece?

Marking the ply number and warp direction on the fabric each time you cut a piece is crucial in aerospace assembly, especially when dealing with composite materials. The ply number refers to the specific layer of fabric being used, which is essential for maintaining the integrity and the structural design of the finished product. Each layer's contributions to strength and flexibility are predefined based on the ply sequence.

The warp direction is also important because the orientation of fibers affects the material's mechanical properties and its performance when subjected to stresses. In composite structures, the way fibers are aligned plays a significant role in how well the material will perform under various loading conditions. Using the correct warp direction ensures that the strength characteristics of the material are optimized for the intended application, which is critical in aerospace components where safety and performance are paramount.