This page is about the regular Bow Limb, used in Shortbows and Longbows. For the Crossbow Limb, look here.
The Bow Limb is the main crafting material for Shortbows and Longbows. The Crossbow uses the Crossbow Limb, a separate item. The bow limb is crafted in a Part Builder with 1.5 of any material. In prior updates, bows were crafted using tool rods. The best materials for crafting bow limbs are the softest- a steel bow isn't going to be the greatest, unless you're making a hybrid weapon. Wood, Cactus and Slime are better than Iron.