Threading Blind Holes
There are three accepted methods of threading blind holes:
- Conventional tapping, especially with bottom taps
- Single-point threading, where the workpiece is rotated, and a pointed cutting tool is fed into the workpiece at the same rate as the pitch of the internal thread. Single-pointing inside a blind hole, like boring inside one, is inherently more challenging than doing so in a through hole. This was especially true in the era when manual machining was the only method of control. Today, CNC makes these tasks less stressful, but nevertheless still more challenging than with through holes.
- Helical interpolation, where the workpiece remains stationary and CNC control moves a milling cutter in the correct helical path for a given thread, milling the thread.
Read more about this topic: Blind Hole
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—Anna Julia Cooper (1859–1964)
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—F. Scott Fitzgerald (1896–1940)
“A person taking stock in middle age is like an artist or composer looking at an unfinished work; but whereas the composer and the painter can erase some of their past efforts, we cannot. We are stuck with what we have lived through. The trick is to finish it with a sense of design and a flourish rather than to patch up the holes or merely to add new patches to it.”
—Harry S. Broudy (b. 1905)