The letters associated with the numbers listed below are
F and
G. As mentioned, F is
fillet, and G is
groove.
#1 Flat Position: When the welder locates the workpiece on the floor or workbench, the position is called the flat position. It is considered the most accessible position because you are not welding against gravity. When using the flat position, it's best to maintain the tip angle, flame position, and consistent motion. The tip should be at a 45-degree angle with the plate surface.
In the flat position, the weld puddle goes
into the joint evenly in a fluid state. The molten metal might be hotter than usual, and the deposition rate will be higher because gravity draws the metal downward at the joint. You can do every welding process in a flat position.
A 1F welding position indicates a flat welding position (1) with a fillet weld (F), while a 1G tells you it's a flat position (1) but with a groove weld (G).