3G Welding Position Explained

Written By: Liam Bryant

The 3G welding position is a vertical welding position often used for plate or groove welding. It demands precision and skill from the welder, requiring the weld to be applied uphill, from bottom to top, on a vertical surface.

welding positions

What is the 3G Welding Position?

When discussing the 3G welding position, we refer to the vertical groove welding position. As a welder, it means I’m working with the surface of a joint or a plate, moving my welding rod from bottom to top vertically. This position, which can also be called “vertical up” or “uphill”, is one of the four basic welding positions – flat (1G and 1F), horizontal (2G and 2F), vertical (3G and 3F), and overhead (4G and 4F).

The “G” in 3G stands for “groove”. Groove welds are usually made in the groove between two parts to be joined. Here, I’d be fusing the edges of the plate or joint together, making sure that the weld pool doesn’t sag or spill out.

Where Do You Use 3G Welding?

I’ve found that the 3G welding position is very versatile, used across different industries. From infrastructure projects like bridges and buildings, to smaller construction tasks, the vertical position comes into play whenever a weld has to be made on a vertical surface.

The vertical position is also commonly used when doing stick welding, a manual arc welding process using a consumable electrode. This process is widely used due to its simplicity and versatility, particularly in outdoor settings, where the wind may affect other types of welding.

Characteristics of the 3G Welding Position

The 3G welding position is characterized by its vertical trajectory. As a welder, I move my torch or electrode from the bottom to the top in a sort of ‘uphill’ motion. The weld is performed on a vertical surface, requiring the bead to be layered evenly to prevent sagging due to gravity.

The vertical welding position requires a steady hand and a keen eye for detail. The speed of your movements, the angle of your electrode, and your control over the molten pool are critical factors determining the final weld’s quality.

What is the Qualification Range for 3G?

A certification in the 3G position qualifies you for all plate welding positions – the flat position (1G), horizontal welding position (2G), and the overhead position (4G). It’s a significant step in any welder’s journey, and having this certification under my belt has given me a sense of accomplishment and the flexibility to work on a wide range of projects.


The primary advantage of the 3G welding position is its versatility. It allows for welding in tight or hard-to-reach areas where laying a flat or horizontal weld is impossible.

I’ve also found that vertical welding often provides a stronger, more resilient weld, which is a significant advantage when working on structures that require high-strength joints.


The 3G welding position can be tricky to master. It requires a lot of practice and a good understanding of how gravity affects the weld pool. It’s all about balance – moving too fast can cause the weld pool to become unstable and spill, but moving too slowly can cause excessive buildup or ‘undercut’ – a groove melted into the base metal adjacent to the toe of the weld.

3G vs 3F Welding Positions

Compared to the 3G position, the 3F or vertical fillet weld position is performed on a flat surface tilted to a vertical position. This weld is typically used when joining two pieces of metal at a right angle.

The main difference between these two positions is the type of weld – while 3G involves a groove weld, 3F is about fillet welds. The techniques used can differ, but both require a steady hand and a knack for precision.


In my journey as a welder, I’ve found that mastering the 3G welding position is a critical skill. It’s not always easy, but its versatility makes it an essential technique to learn. Remember that each welding position, whether flat, horizontal, vertical, or overhead, brings unique challenges and rewards. Practice and persistence are key.