STG Machine has published some articles recently on helicoils and how to install them, so we thought it would be helpful to share our knowledge on how to remove them. It is common to see drawings or dimensions change which requires the removal of helicoils to rework parts. Below you will find a few tips on how to remove helicoils.
Extraction Tool
Removing helicoils is a very difficult task, but it can be done with a helicoil extraction tool. This tool has a sharp blade that must be inserted at the top of the helicoil, and while being held in position strike the back of the tool with a hammer. This should wedge the tool into the helicoil and it can then be removed by turning counter clockwise.
Often times you will have to make a custom tool in order to get this option to work. We will sometimes grind down existing taps or drills to a point to give us the angle and depth needed to grab a helicoil. This alternative method also allows you to retrieve helicoils that are sitting deep within a part which otherwise would be impossible to reach.
Hand Tool Option
If the extraction tool doesn’t work then there is another option available. This involves using a pair of pliers to get in between the helicoil and the tapped hole. Once the helicoil is lifted or pulled out slightly, use a pair of pliers to rip the helicoil out. This will most likely damage the thread so you will need to chase the thread afterwards. The removed helicoil will obviously be damaged beyond repair, and be careful not to damage the thread excessively during the extraction.
If you have any questions or comments please feel free to leave a comment down below!
Julien
June 16, 2023 at 5:48 pm
As a last resort, would it be possible to drill it out with a cobalt drill bit? If there is enough surrounding metal to use a different type of insert (such as ez lok). I was told they are too hard to drill, but surely there are tools that are up to the task?
STG Machine
June 28, 2023 at 10:28 pm
@Julien, yes you can try drilling a helicoil out as well.
However, with small helicoils this strategy may not work since the exterior wall of the helicoil is so thin.
Attempting to drill out smaller helicoils may result in damaging the tapped hole inside of the part.