Invented: Tod E. McQuaid (1954-1990)
Method of extracting broken key takes some skill but is doable.
Tod owned two companies and was forming a third in Lewisburg, West Virginia. One can only guess if some magnificent invention was coming. His death ended his inventing.
It all started with TEMAC (T. E. McQuaid Alarm Company). A broken security key was more difficult because it was smaller, the equipment carried to repair alarms was not guaranteed to work on a key, and the locksmith was not a financially viable option.
Here is a cheap option for extracting the broken portion of key inside the lock:
Obtain a tube of plunger type "crazy glue"!
Place minute quantity on broken end of key outside the lock.
Immediately place in key hole against inside key piece for two seconds.
Remove outside broken key piece.
Add a second thin coat of crazy glue.
In ten seconds, return broken key into slot against inside key piece.
After one minutes of holding pressure, slowly extract the complete key.
Warning: Care must be exercised to ensure that crazy glue is not placed on side of key. In addition, care will probably not work if glued key is used in attempt to open lock.
Above procedure found in office of TEMAC after Tod's death.