Abstract: Apparatus for and a method of precisely positioning an object to be subjected to localized heating at precise temperatures at the second focal point of an elliptical reflector which has an infra-red source at its first focal point. The apparatus includes a platform to support the workpiece for vertical movement relative to the reflector and infra-red source, and a movable probe which has a free end positionable in the axis of the reflector and in the plane of its second focal point to guide movement of the platform and workpiece to the second focal point.