Once a new welder can run a straight bead, the next question is usually whether to weave. Weaving looks impressive, that rhythmic side-to-side motion laying down a wide, rippled bead, and beginners often want to do it everywhere. But stringer beads and weave beads are tools for different jobs, and reaching for the wrong one causes real problems. Knowing when to keep it straight and when to weave is a mark of someone who understands what the weld actually needs.
The Two Beads
A stringer bead is the straightforward one. You move the torch or electrode in a straight line down the joint with little or no side-to-side motion, laying a narrow, consistent bead. Stringers are precise, predictable, and put a controlled, relatively low amount of heat into the metal.
A weave bead is made by oscillating the torch from side to side as you travel forward, sweeping out a wider bead in a single pass. The weave can follow various patterns, a simple side-to-side, a zigzag, a series of small circles, but the principle is the same: cover more width in one pass. A weave fills a wider area and, because it lingers, puts more heat into the joint and slows how fast the weld cools.
Heat Input Is the Real Difference
The reason this matters comes down to heat. A stringer concentrates the arc in a narrow path and moves on, so it deposits less heat per inch of joint. A weave spreads the arc back and forth over a wider area and takes longer to cover the same distance, so it pumps more heat into the metal and keeps it hot longer.
For some jobs that extra heat is fine or even helpful. For others it is a problem. High-strength and low-alloy steels can lose strength and toughness if they get too much heat and cool too slowly, which is the same concern behind preheat and interpass temperature control. That is why the choice between stringer and weave is not just about appearance. It is about managing how much heat the steel sees.
When to Use Each
Reach for stringer beads when you want control and lower heat. Root passes, where precision and penetration matter most, are usually stringers. Thin material, where a wide weave would dump in too much heat and warp or burn through, calls for stringers. Heat-sensitive steels call for stringers. And anywhere a welding procedure or code restricts heat input, stringers are usually the answer. A common professional approach to filling a wide, thick joint is to run multiple stringer passes side by side rather than one big weave, which keeps heat input controlled while still filling the groove.
Reach for a weave when filling width efficiently is the goal and the steel can take the heat. Capping passes, where you want a uniform wide finished bead, are a natural place to weave. Filling a wider gap in a single pass can justify a weave. And in some out-of-position work, a controlled weave helps manage the puddle. The key is that weaving is a deliberate choice for a wider, hotter bead, not a default.
Mind the Width
When you do weave, width has limits. Because a wide weave adds so much heat and slows cooling, many welding procedures cap the weave width, often as a multiple of the electrode or wire diameter. Exceeding that can take the steel outside the heat input range the procedure was qualified for and weaken the joint. If you are welding to a code or a procedure, follow its weave width limit rather than eyeballing it.
For most beginners learning on mild steel, the practical takeaway is simple. Master the stringer bead first, because it teaches control and it is the right choice more often than people expect. Add weaving as a deliberate tool for wider fills and caps once you understand the heat tradeoff. And when you are unsure on an important joint, a series of clean stringers is almost always a safe bet over one ambitious weave. Build both into your practice routine so you can run either on demand and pick the right one for the job in front of you.