A rotary actuator and a method of additively manufacturing the same are provided. The rotary actuator includes a valve housing defining a valve chamber and a shaft channel extending from the valve chamber. A valve body includes a valve shaft extending through the shaft channel and a valve head positioned within the valve chamber and defining a head width that is larger than the channel diameter to inseparably join the valve body and the valve housing. The valve head divides the valve chamber into a first chamber and a second chamber which are in fluid communication with a first port and a second port, respectively. The valve body is rotated by adjusting a fluid pressure within at least one of the first chamber and the second chamber.