Which tap is optimal for cutting threads near the bottom of a blind hole?

In the context of cutting threads near the bottom of a blind hole, a bottoming tap is the optimal choice. This type of tap has a flat end, allowing it to create threads all the way to the bottom of the hole effectively. Unlike other types of taps, such as taper taps or plug taps, which have a gradual lead-in that helps in starting the threading process, a bottoming tap is specifically designed to finish the threading in confined spaces like the bottom of a blind hole.

The flat design of the bottoming tap ensures that it can engage fully with the material at the very bottom, ensuring that maximum thread engagement is achieved. This characteristic is essential for applications where the strength of the threaded connection is critical, as it maximizes the length and quality of the threads formed in the material. Therefore, for tasks requiring threading deep within blind holes, the bottoming tap is the go-to tool.