The workhorse weld of fabrication, filling the inside corner where two members meet at or near 90 degrees and showing a triangle in cross section. It is sized by leg length, while its strength depends on the throat. Fillet welds need no edge preparation, which makes them cheaper than groove welds, and inspectors check them for undersize, undercut, overlap and excess convexity.
Quarter-inch fillet weld both sides on the stiffeners, check the legs with the gauge before you move on.
Also heard as
- fillet
Related terms
Leg
How far a fillet weld reaches along each member from the corner, the dimension used to call out fillet size.
Throat
The thinnest section through a fillet weld, from the joint root to the face, which sets how much load it carries.
Toe
The edge of a weld bead, where weld metal blends into the surface of the base metal.
Groove weld
A weld made in a prepared opening between two members, such as a beveled butt joint.
Weld position
The orientation of a joint during welding, coded 1 to 4 for flat, horizontal, vertical and overhead.