4.1.1. Striking surface: Padded surface of a weapon designed to make contact with a combatant during combat. Only the striking surface of a weapon may score a hit.
4.5.1. Two and one-half inch rule (6.35 cm): No surface on a striking edge (sword tip, arrow/bolt head, spear head, javelin head, etc.) whether designed for stabbing or not, may readily pass more than one-half (1/2) inch (1.3 cm) through a two and one-half (2 1/2) inch (6.35 cm) hole.
4.5.1.1. The weapon tip is exempt from the two and one-half (2 1/2) inch (6.35 cm) rule, rule 4.5.1, if the weapon has a semicircular tip with a minimum one and one-half (1 ½) inch (3.81 cm) radius.
Effectively, then, the minimum striking surface dimensions are determined by physics. The weapon and its striking surface should have the integrity to not break too quickly, the weapon must end up delivering safe and reasonably nice strikes, and the weapon's striking surface can't fit through too small of a hole.
So, veteran foamsmiths of the Bel boards, what is your advice to reasonably experienced foamsmiths regarding building a weapon with minimal striking surface? In particular, what width, length, and depth of striking surface would you suggest for different weapon types and weights?