A solid material delivery system for a furnace which melts the solid material has a delivery tube located at least partially within the furnace which is mounted by a rotor assembly for selective radial positioning in the furnace over a crucible in the furnace. The rotor assembly is constructed to compensate for thermal expansion and contraction caused by the furnace so that free movement of the delivery tube is achieved at all operating temperatures. The rotor assembly is also constructed to prevent jamming caused by particulate solid material in the rotor assembly. The delivery tube is formed so that flowable solid material will flow in a controlled fashion but without clogging to an outlet. The delivery tube and outlet are shaped to drop the material in a substantially columnar stream into the crucible.