What is the maximum size fillet allowed along an edge of a 15/16" plate in a lap joint?

In a lap joint, the size of the fillet weld is typically governed by the thickness of the materials being welded. According to AWS D1.1, the maximum size of a fillet weld cannot exceed the thickness of the base material being joined. For a 15/16" plate, the maximum allowed leg length of the fillet weld would be equal to or slightly less than the thickness of the plate.

When considering the size of the fillet welds, a common rule of thumb is that you can have weld sizes that equal to the plate thickness, but you often see a maximum size slightly less than the plate thickness to ensure proper joint integrity and to allow for effective puddle formation. Therefore, for a 15/16" thick plate, a 7/8" fillet weld is allowed, as it is just under the thickness of the base material and within acceptable limits for joint strength and performance. This ensures that the weld can adequately penetrate and fuse to the base material without causing issues such as burn-through or inadequate weld formation.

Plate thicknesses also correlate with weld sizes to maintain structural integrity and performance standards in welded joints. In this context, a larger weld size, such as 1", may not effectively bond the