How to Deal with a Broken Tap or Drill Bit Stuck in a Hole?

The breakage of tools and cutters is a significant factor affecting product quality. Traditional methods for dealing with broken taps or drill bits are often inefficient and ineffective. Here are some efficient solutions:

Lubricating Oil Dropping and Tapping Method

Drop lubricating oil at the point of fracture and gently tap with a pointed tool to gradually withdraw the broken part. This method is suitable for most cases but may not apply to taps with too small a hole diameter or those with an excessively long broken part.

Welding Hex Nut Reversal Method

Weld a hex nut to the broken tap and then gently reverse it out. This method is suitable for taps with a larger diameter but not for those with a small diameter.

Use of Tap Extractor

Utilize a specialized tool – the broken tap extractor – which removes the broken tap from the workpiece through the principle of electrolytic corrosion, causing minimal damage to the inner hole.

Steel Rod Against the Crack Method

Use a steel rod to apply pressure to the crack in the tap and gently tap with a hammer to fragment it before removal. This method may not be very suitable if the tap diameter is too large or too small.

Electric Pulse Removal Method

Use electric pulse technology, such as electric discharge machining or wire cutting, to remove the broken part. If the hole is damaged, it can be reamed and repaired with a wire thread insert.

Reverse Pulling Out Method

Create a simple tool to insert into the chip channel of the broken tap and carefully pull it out in reverse. This method is suitable for taps with a chip channel and can be efficiently removed with a specially made tool.

Conical Tool Prizing Method

Use a hard conical tool to prize out the broken part, suitable for brittle materials but may damage the original hole.

Special Screw Treatment Method

If the screw head is sheared off, first drill a positioning hole, then use a smaller drill bit to drill, and finally remove the remaining bolt with a left-hand tap, ensuring the external thread remains intact. While these methods can remedy broken tap issues during machining, the best strategy is still prevention. Optimizing processes and operations to avoid breakage as much as possible is key to improving product quality rates.