Handcuff key ergonomic handle

It is common for people to complain about the design of the standard handcuff keys due to their poor ergonomic design. This design aims to improve ergonomics without altering the original key. It is necessary to modify a nail or another piece of metal to use the lock system. In my case, I have used a nail and to insert it, simply heat it with a blowtorch or lighter. Initially, there is no need for anything to secure the key inside the print; even if it is a bit loose, it will still work. In my case, I have used glue, maybe It is better to use epoxy, but be careful not to damage the printing base.

It is necessary to pause before starting to close the handle. I have shared a pre-prepared gcode for the KP3s (with Marlin to pause the print), but it may also work for yours.