For non-utility grade installations, what is stated about cross-sanding?

In the context of non-utility grade installations, cross-sanding refers to the technique of sanding wood across the grain instead of with it. This method is generally not recommended because it can create visible scratches and uneven surfaces that affect the overall finish and appearance of the woodwork.

The statement that cross-sanding is not allowed except for curved stock reflects the practical consideration that, when working with curved pieces, sanding across the grain may be unavoidable to achieve the desired contour and smoothness. In these specific cases, the benefits of achieving a smooth surface on a curve can justify the use of cross-sanding, while in other situations where the grain runs straight and is visible, avoiding this technique is crucial to maintain the aesthetic quality of the finish.

For non-utility grade installations, maintaining a high-quality finish is essential, and avoiding cross-sanding unless absolutely necessary (like for curved stock) helps achieve that high standard.