What aspect primarily determines the strength of a fillet weld?

The strength of a fillet weld is primarily determined by the effective throat dimension. This measurement refers to the shortest distance from the root of the weld to the face of the weld, which directly influences the load-carrying capacity of the weld. A larger effective throat dimension means that more material is present to absorb and distribute stress, thereby enhancing the weld's overall strength.

While the length of the weld can impact the total amount of material in the weld, it does not directly correlate to the strength in the same way that the effective throat dimension does. The weight of the material involved in the welding process can also have relevance in certain contexts, but it is not a direct factor in determining weld strength. Similarly, while the type of welding filler used can influence the weld's overall characteristics and performance in specific applications, the effective throat dimension remains the key factor in the fundamental strength of a fillet weld.