4F Welding Position Explained

Written By: Liam Bryant

The 4F welding position, also known as overhead welding, involves welding from underneath a joint. This position is tricky, requiring precision and expertise, but it’s invaluable for certain applications, such as in industries where metal structures must withstand rigorous vertical loads.

welding positions

What is the 4F Welding Position?

The 4F welding position, commonly called the overhead position, is a unique welding position that’s generally considered one of the most challenging to master. Here, the welder works beneath the joint, which means gravity is working against you. Welding overhead, the molten metal wants to drip down, often resulting in a less clean weld if you’re not careful.

I remember my first encounter with the 4F welding position as an entry-level welder. It felt awkward, unconventional, and yes, a little bit scary. I quickly learned that this position required a whole new set of skills and attention to detail compared to more common positions like the flat welding position.

Where Do You Use 4F Welding?

The 4F welding position, despite its challenges, has its unique applications where it becomes inevitable. Any situation where an overhead joint is required or where the structure can’t be moved to accommodate a more comfortable welding position necessitates 4F welding.

I’ve seen 4F welding used extensively in constructing heavy machinery, buildings, and bridges. Also, in some repair work, especially when it’s not practical to move large, heavy parts, 4F welding is the go-to technique.

Characteristics Of The 4F Welding Position

In the 4F welding position, we mainly do fillet welds on a plate. The name “4F” itself reveals its nature: ‘4’ refers to the overhead position, and ‘F’ denotes fillet welding. Typically, you’d be welding a horizontal fillet weld along a vertical surface.

I’ve noticed over the years that maintaining the right angle and speed is critical in the 4F position. An important tip I often share with fellow welders is to adopt a technique called “backhand” or “drag” technique. This technique lets you see the puddle clearly, helping you control the weld better.

What is the Qualification Range for 4F?

A welder certified in the 4F position can also weld in the 1F (flat) and 2F (horizontal) positions. The idea is, if you can successfully manage to control the weld pool in the challenging 4F position, you can handle the less difficult flat and horizontal positions.

But remember, becoming proficient in 4F welding doesn’t happen overnight. I recall spending countless hours watching Youtube videos and practicing on scrap metal before I felt confident enough to take on a professional project.


One of the greatest advantages of the 4F welding position is its applicability when other positions can’t work. Whether it’s inaccessible locations or the immovability of the structure, 4F welding can be a lifesaver. Plus, mastering this position undoubtedly sets you apart in the field, opening more welder jobs opportunities.


However, the 4F welding position is not without its drawbacks. It’s physically demanding, and the risk of falling debris, particularly molten metal, is higher. Additionally, it requires a high skill level to consistently produce clean, quality welds.

4G vs 4F Welding Positions

The 4G and 4F welding positions involve overhead welding, but they differ in the type of weld. While 4F is used for fillet welds, 4G is used for groove welds. Understanding these differences is essential for choosing the right technique for the job.

In my experience, the 4G position tends to be even more challenging due to the wider groove that needs to be filled compared to the narrower fillet in 4F welding. However, both require similar skill sets and present their unique challenges.


The 4F welding position, while challenging, is an essential skill for any serious welder. Mastering this technique opens up a world of opportunities and allows you to take on projects that others might shy away from. The path to mastery isn’t easy—I’ve had my share of burns and messy welds. But with perseverance, patience, and the right guidance, the 4F position can become second nature.