Which procedure is primarily correct when using a reamer to finish a drilled hole?

When using a reamer to finish a drilled hole, it is essential to turn the reamer only in the cutting direction. This practice is important because reamers are designed with cutting edges that efficiently remove material when turned in one direction. Turning the reamer backward can cause it to bind in the hole, leading to damage to both the reamer and the workpiece.

Moreover, maintaining the reamer in the cutting direction ensures a smooth and accurate finish, which is necessary for achieving the desired tolerances and surface quality. This technique is foundational in metalworking and helps prevent issues such as chatter or uneven cutting, which could result from inappropriate direction during operation.

While lubrication and other techniques may enhance the reaming process and ensure better outcomes, they do not fundamentally alter the necessity of adhering to the proper directional operation of the reamer. Therefore, turning the reamer only in the cutting direction is a critical aspect of the correct reaming procedure.