The is an overhead fillet weld where the joint is positioned above the welder, typically in a T-joint or lap joint configuration. To produce a "solid piece" (a high-quality, defect-free weld), you must master the following techniques: 1. Core Principles for a Solid 4F Weld
for different material thicknesses.
To better understand the paper's findings, it helps to note the general industry consensus on 4F welding: 4f welding position full