Stringer Bead vs Weave Bead — What It Is and Why It Matters
A stringer bead is a weld bead deposited in a straight line with no side-to-side manipulation — the torch or electrode travels in a direct path along the joint. Stringer beads produce narrow, consistent deposits and are the standard technique for root passes, fill passes in narrow grooves, and any application where controlled heat input matters.
A weave bead involves moving the electrode or torch side to side in a deliberate pattern (zig-zag, crescent, figure-eight, or triangle) while traveling along the joint. Weave beads produce wider deposits, cover more area per pass, and are used for cap passes, wide groove fills, and fillet welds where a wider bead is efficient.
The choice between stringer and weave depends on joint configuration, position, and code requirements. Many codes limit maximum weave width (typically 2-3 times electrode diameter) because excessively wide weaves increase heat input, slow travel speed, and can cause defects. Stringers are generally preferred for vertical-up welding; controlled weaves are common for cap passes and horizontal fillets.
Frequently Asked Questions
When should I use stringers versus weave?
Use stringers for root passes, narrow groove fills, heat-sensitive materials, and vertical-up welding where a small pool is easier to control. Use weave beads for cap passes to achieve full width coverage, for wide fillet welds, and for horizontal positions where the weave allows the pool to fill the joint fully. Many welders alternate — stringers for fill passes, weave for the cap.
How wide can a weave bead be?
Most codes limit weave width to 2-3 times the electrode core wire diameter, or sometimes a fixed dimension (e.g., 3/4" maximum in some AWS D1.1 provisions). Excessively wide weaves cause excessive heat input, slow travel speed at the edges, and potential lack of fusion at the center. Check the applicable WPS for specific weave width limits.