Drilling Out Broken Tools: Techniques and Tools

Assessing the Breakage Before Extraction Every deep hole driller breaks tools eventually. When a gun drill breaks in the bore, the first step is not to panic. I assess the situation before deciding how to extract the broken tool. I ask myself three questions: where in the bore did it break, how deep is the broken piece, and is the tool jammed or loose. The location of the break matters more than most people realize. If the tool broke near the entry, I have more options. A break at the far end of a deep bore changes my strategy entirely. I use a borescope to examine the break point before committing to any extraction method. In my experience, thirty minutes of inspection saves hours of trial-and-error extraction work. ...

June 12, 2026 · Engineer at the Deep Hole