I. Stripped but not completely damaged screws: Prioritize non-destructive removal.
1. Increase friction to unscrew:
Place a rubber sheet, electrical tape, or rubber band under the screwdriver head to enhance grip, and slowly apply force while unscrewing counter-clockwise.
Use needle-nose pliers to grip the screw head (if exposed) and rotate counter-clockwise to remove it.
2. Heat melt method (suitable for plastic parts):
Heat the screw head with a soldering iron for a few seconds to soften the surrounding plastic. Pull or unscrew it while it's still hot. Suitable for electronic devices or plastic casings.
II. Severely stripped or broken screws: Use professional tools to remove them.
1. Screw extractor (broken thread extractor):
Drill a small hole in the center of the stripped screw, screw in a screw extractor with the reverse thread, and rotate counter-clockwise to pull the screw out.
Note: Drilling must be precise to avoid damaging surrounding structures.
2. Welding-Assisted Method
For large screws, a metal rod can be welded to the top to increase the torque and loosen it using leverage.
Suitable for metal parts where space allows, but the impact of high temperatures on surrounding components must be considered.
III. Stripped Threads: Repairing Threads or Enhancing Connection Strength
1. Retapping (Enlarging Threads)
Use a larger tap to re-tap the original threaded hole to match a larger screw.
Suitable for metal parts, but this will change the original design dimensions; the structural impact needs to be assessed.
2. Thread Insertion (Threaded Insert)
Install a wire thread insert (such as Helicoil) to restore the original thread specification while improving wear resistance and tensile strength.
Widely used in high-requirement applications such as engines and precision equipment.
3. Filling Repair Method
Fill the damaged threaded hole with metal repair adhesive or epoxy resin, and re-drill and tap after curing.
Suitable for small hole repair, but requires a longer curing time, and the strength is slightly lower than the original thread.
4. 502 Glue Temporary Fixing Method
Drip a small amount of 502 glue into the screw hole, quickly screw in the screw. After curing, it provides temporary fastening force, suitable for non-load-bearing connections.
IV. Key Measures to Prevent Re-stripping
1. Use power tools with controllable torque to avoid over-tightening;
2. When installing in plastic parts, control the screwing speed and depth to avoid heat buildup;
3. Use self-locking screws or threadlocker for high-vibration areas;
4. Regularly check the wear of tool bits and replace them promptly.
⚠️ Special Reminder: If critical structural components (such as mechanical equipment or vehicle parts) are involved, it is recommended to have them handled by professionals to avoid safety hazards caused by improper repairs.
