These rules originally appeared in Swords at Dawn, pp 50. They are reproduced here for convenience.
Most whips are six-foot long (or longer) weapons of braided leather. They require more finesse to use than a baseball bat (or short sword), and thus attacks with a whip are rolled with the attacker’s Dexterity + Weaponry. Most whips inflict 1(B) damage, though a character might affix metal objects at the end of the whip to upgrade the damage to 0(L).
No matter the type of whip, a character can make an attack with a whip at a –3 penalty to disarm an opponent. Even a single success demands that the opponent roll Strength + Stamina — attacker’s Dexterity to retain his grip on his weapon. (Note that the opponent takes no damage from this attack.) A character may use Bite of the Wooden Fang to supplement this roll: the invisible barbs help grip the weapon in question.
Whips appropriate for the use of Bite of the Wooden Fang (Contracts of Thorns and Brambles •) are made of somewhat less sturdy stuff, however, and inflict only 0(B) damage. While such a whip can be upgraded to –1(L) with the attachment of pieces of metal or similarly dangerous objects, such upgraded whips cannot be used with the Contract.