A medical stent mold includes a tube having an interior passage sized and dimensioned to receive a stent assembly disposed at least partially about a central portion of a stent balloon. The medical stent moid may also include a bousing forming a chamber through which the tube extends. The tube may include a thermally conductive material and may have a body portion that extends within the chamber and an end portion that is proximate the body portion and that extends away from the housing. An inner diameter of the end portion of the tube is greater than an inner diameter of the body portion of the lube. Forced convection may be used to quickly heat and cool the tube. Methods of increasing retention of an expandable stent assembly on a stent balloon and of detecting a leak in a stent balloon are also included.