Don't Blame It on the Tap! Hole size and condition just might be the problem

摘要

When diagnosing problems with internal threading, a machinist often overlooks the size and condition of the hole before threading. Of all the thread-making processes, tapping seems to suffer the most from this oversight. Thread mills will usually overcome the issues that can cause taps to fail, making them an attractive option for most applications. Other factors such as toolholding, workholding, machine condition, and lubrication also can have a significant effect on the tapping operation. A tap failure is usually blamed on a "bad" tool when, most likely, there is nothing wrong with the tap itself; it just might not be ideal for the machining conditions. It is crucial to look at the tapping process, not just the tool, to achieve a good finished product.