Darrell,
WELCOME TO THE AWS WELDING FORUM!!
I'm going to rest with John's response for the time being.
Now, is this who I think it is??
Have a Great Day, Brent
The only reference I see to "Maximum size of Fillet welds" is in AISC Steel Construction Manual, 14th Edition, p16.1-111, 2b. The information there only relates to leg size in relation to material size and weld length.