Torch angles — comparing forehand (leftward) and backhand (rightward) gas welding Relative to backhand welding, the angle between the torch and the work in forehand welding is typically:

Introduction / Context:
In oxy–fuel welding, torch and filler rod angles govern heat distribution, bead contour, and penetration. Two principal techniques are forehand (leftward) and backhand (rightward). Understanding their geometry helps select the suitable method for thickness and joint type.

Given Data / Assumptions:

• Forehand (leftward) technique is used mainly for thin to moderate sheets.
• Backhand (rightward) technique suits thicker sections requiring deeper penetration.
• Angles given are typical classroom values, not absolute rules.

Concept / Approach:
Forehand welding generally uses a smaller torch angle relative to the work surface (often around 40°–50°), with the torch pointing in the direction of travel to preheat ahead of the puddle. Backhand welding uses a larger torch angle (often around 60°–70°) with the torch trailing the puddle for concentrated penetration. Hence, the forehand torch angle is “less” than that used in backhand.

Step-by-Step Solution:

Verification / Alternative check:
Demonstration welds show broader preheat and lower penetration in forehand at the smaller angle; macro-sections confirm profile differences.

Why Other Options Are Wrong:

• Same: contradicts standard teaching.
• More: backhand uses the greater angle.
• “Always > 80°”: impractical and not representative.
• Indeterminate: while angles are adjustable, typical practice clearly differs.

Common Pitfalls:
Confusing torch and rod angles; using backhand angles on thin sheet and causing burn-through or distortion.

Final Answer: