A method for manufacturing pellets of hot-melt ink which includes the steps of filling molten ink into a mold cavity defined by a first die and a second die of a mold, allowing the ink to cool down and solidify in the mold cavity, and heating at least one of the first and second dies for re-melting the surface of the ink pellet to facilitate its removal from the mold cavity. Wireless station computes at least some future time instances at which another wireless station is expected to start transmitting control messages. The replacement casting includes an airfoil stub.