If a bolt head is badly rusted and difficult to loosen, who is right between Technician A, who recommends pliers, and Technician B, who suggests a six-point wrench or socket?

Using a six-point wrench or socket is the most effective method for loosening a badly rusted bolt. The design of a six-point tool provides a better grip on the flats of the bolt head, which minimizes the risk of rounding off the corners, especially when the bolt is rusted and may require a significant amount of torque to break free. The six points evenly distribute the load on the bolt head, reducing stress and increasing the chances of successfully loosening the bolt without causing damage.

Pliers, while they may be able to provide some grip, are not ideal for this situation. They can slip off the bolt head, particularly if the rust is significant, leading to potential injury or further damage to the bolt. Additionally, pliers do not provide the same level of torque application as a wrench or socket, making them less effective for stubborn rusted bolts. Therefore, Technician B’s recommendation is the more appropriate choice for dealing with a rusted bolt.