Practice exam query: joint B-L2c-S (page 96), range of root face as fit up, base metal 1 inch thick.
Being timed I was rushing, and answered 3/16 - 5/16, as f = 1/4" inch max +/- 1/16".
Correct answer 0 - 5/16".
Obviously as a joint with complete penetration, bottom of tolerance for 'f'...