What do extension lines indicate in a dimension?

Extension lines are important elements in technical drawings, particularly in dimensioning. They serve to convey essential information about measurements and how they relate to the object being represented. Specifically, extension lines indicate the termination points of a dimension. They are typically drawn from the edges of the object to the dimension line, helping to clearly define where the measurement starts and ends.

In dimensioning, extension lines help maintain a clear visual connection between the dimensions and the physical features of the object. By indicating where dimensions begin and end, they ensure that anyone interpreting the drawing can accurately understand the intended measurements, which is crucial for manufacturing, fabrication, or assembly processes. Thus, recognizing the role of extension lines in indicating the termination of dimensions is fundamental for anyone in the field of welding or engineering drawing interpretation.