4F Welding Position — Complete Guide
Definition (AWS A3.0)
- 4F = Overhead fillet weld.
- The weld is deposited on the underside of a horizontal member with a vertical member extending downward.
- The welder works with the weld pool above them.
- Gravity pulls the molten metal downward (away from the joint), making it the most difficult fillet position.
4. True 4F: The Overhead Fillet Weld
Now, let's address the true AWS 4F position: Overhead Fillet.
In 4F, the welder is below the joint. The two plates form a corner above your head. Gravity pulls the molten metal straight down—onto you and your equipment.
Mastering the 4G (4F) Welding Position: A Complete Guide to Overhead Welding
In the world of welding, proficiency is often measured by your ability to join metal in difficult positions. While welding on a flat table is comfortable, real-world fabrication often requires you to work against gravity.
The 4F welding position (often referred to as Overhead Welding) is widely considered one of the most challenging certifications to obtain. It tests a welder’s skill, steadiness, and understanding of puddle control.
This guide covers everything you need to know about the 4F position, from definitions to practical tips for passing your test.
Polarity and amperage
- Follow consumable manufacturer's WPS values. Overhead often uses slightly lower travel speed and controlled heat input:
- SMAW: set amperage per electrode diameter and position (e.g., 1/8" rod ≈ 70–120 A depending on type).
- GMAW/FCAW: reduce wire feed or voltage slightly from flat position to control puddle sag; use short-circuit or pulsed modes to minimize drip.
- Use direct current electrode positive (DCEP) or as specified for penetration control.
