Why do the locking keys fail to keep the inserts from turning in aluminum?
A4. The keys do not extend outward far enough to get past the threads. The locking pins used to secure the Full-Torque inserts extend into the solid metal beyond the threads preventing rotation even in heated aluminum. Q5. Can I stack the key locking inserts on top of each other to repair a deep hole. A5. No, the keys need to be removed if the insert is installed below the surface so there is no way to keep it from turning and locking up on the bolt as the two inserts get out of time with each other. Full-Torque inserts are made long enough to meet your needs.
