Above is an example of a threaded hole in section using standard simplified convention. A threaded hole is produced by two operations. A hole is first drilled in the stock, then a tapping tool is used to cut the threads. Rather than drawing the threads as they would actually appear, the simplified convention shows the threads as hidden lines. The threads are not shown to extend to the bottom of the hole. This is due to the fact that the tapping tool is tapered to facilitate starting the operation. Therefore, the threads at the bottom of the hole are "bad."