What is the primary distinction between stringer beads and weave patterns in welding?

Stringer beads are characterized by their straight, linear application of weld metal. This technique typically involves moving the welding torch or electrode in a direct line without any lateral motion. The result is a narrower, concentrated bead that penetrates deeply into the base material, making it suitable for vertical or overhead positions and helping achieve good fusion, especially in thinner materials.

In contrast to stringer beads, weave patterns involve a side-to-side motion that creates a wider weld bead. Weaving helps in distributing heat more evenly across the joint, making it beneficial for wider joints or when the welding process needs to accommodate thicker materials.

The other options do not accurately capture the essence of stringer beads. For instance, stringer beads do not involve a side-to-side motion, nor are they defined by being used specifically for thicker materials or involving straight lines of welds in the traditional sense. They are best understood as direct, straight applications without lateral movement, which is why the provided answer aligns accurately with the definition and technique of stringer beads in welding.