Abstract: Methods of manufacturing engines are disclosed. A single-piece core is printed based on specifications in a three-dimensional print file. The single-piece core is then used in a casting process to create an engine. The three-dimensional print file includes specifications corresponding to each hollow interior feature of an engine. The three-dimensional print file may include specifications for one or more accessory features, and the single-piece core may be printed to include the one or more accessory features.

Abstract: A pulsating attachment for use with an electric hair dryer that has a tubular end through which air is expelled is described comprising a coupling section with an asymmetrical and unbalanced single impeller supported in the coupling for rotation therein and mounting structure connecting the coupling and the tubular end whereby the expelled air rotates the impeller and, due to its unbalanced mounting, creates a pulsating flow of air at a constant flow rate from the coupling. This results in a rotating path of pulsating air on the head of the user to create a fluffing action.