Symptoms
- Screw head rounds out or strips before fully seated
- Screw snaps off, especially smaller gauge screws
- Driver bit cams out of the screw repeatedly
- Screws sink too far into soft material
Likely causes
- CommonDriver bit doesn't match the screw head size/type exactlyA slightly wrong bit size is the single biggest cause of stripped or rounded screw heads.
- CommonFull trigger pressure used on small or brittle screwsImpact drivers deliver much higher torque than a standard drill and can snap small screws instantly.
- PossibleWorn or rounded driver bit tipA worn bit slips under high torque instead of gripping the screw head.
- PossibleNo clutch to limit torque, unlike a standard drillImpact drivers rely on trigger control and technique instead of a torque clutch.
- Less commonDriving into material that's too dense for the screw sizeExcess resistance combined with high torque overloads the screw itself.
What to do
- Match the driver bit precisely to the screw head type and size before starting.
- Use lighter, more controlled trigger pulls rather than full pressure, especially on small screws.
- Replace driver bits often; a slightly worn tip causes most cam-out and stripping problems.
- For delicate or small-gauge screws, consider using a standard clutch drill/driver instead of the impact driver.
- Drill a pilot hole for screws going into dense or hard wood to reduce the resistance the impact driver has to fight.
- Practice easing off the trigger just as the screw seats flush, rather than holding full power to the very end.
Tools and parts
- Fresh impact-rated driver bits
Impact-rated driver bit setSearch: “impact rated screwdriver bit set”
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.