AG Mechanics CDE Practice Exam 2026 - Free AG Mechanics Practice Questions and Study Guide

Flat weld is considered to be the most difficult due to its position and constant need for vertical movement. Flat welding often requires working on a horizontal plane that can make it challenging to achieve proper penetration, maintain an even bead, and avoid burn-through. In contrast, the other options (horizontal, vertical down, and vertical up weld) typically involve more stable positions and more manageable movement patterns, making them less difficult.