If you have ever looked at a technical drawing and wondered, "Is that edge supposed to be sharp? How sharp is 'sharp'?" — you are not alone.
Simply put: It tells the machinist how to treat the "leftover" edges—those small intersections between two surfaces where no specific radius or chamfer is called out. din iso 13715
Let’s break down what it is, why it matters, and how to read its symbols. Officially titled "Technical product documentation — Indications for undefined edges," DIN ISO 13715 specifies how to indicate the permissible condition of edges that are not explicitly dimensioned elsewhere on the drawing. If you have ever looked at a technical
Here is what the symbols mean: