How to Remove a Stripped Screw (and Stop Stripping Them)

To remove a stripped screw, start with the method that does the least damage: press a wide rubber band or a piece of abrasive pad between the bit and the head, use a fresh bit one size larger if it will seat, and turn slowly with heavy downward pressure. If that slips, tap a slightly larger Torx or hex bit into the damaged recess, then try a left-hand drill bit, then a screw extractor. If the head stands proud, grip it with locking pliers or cut a new slot. Drilling the head off is the last resort.

To stop it happening again, match the bit to the recess exactly, seat it fully, push in line with the screw, and slow the driver down. Stainless steel screws need this more than most: the metal is relatively soft, so a poorly seated bit rounds the recess quickly, and a thread that is starting to bind (galling) feels like a screw that just needs more force.

Which removal method should you try first?

Work down this list in order. Each step does more damage than the one before it, so only move on when the current one has failed.

The rest of this article walks through each one.

How do you get grip on a stripped screw head?

Rubber band or abrasive pad. Lay a wide rubber band (or a square cut from a green scouring pad) flat over the head, push the bit through it into the recess and turn slowly by hand or at the lowest driver speed. The material fills the gaps where the recess has rounded out. This often works on Phillips and slotted screws that have only cammed out once or twice.

Go up a size, or change the bit shape. A Phillips recess that the #2 bit chewed up will sometimes take a #3. For a stripped hex socket on a socket head cap screw or button head cap screw, the usual trick is to tap a Torx bit or the next hex size into the rounded socket with a light hammer so its points bite into the walls, then turn it out by hand. Use a bit you are willing to throw away, and don't use an impact driver for this: the hammering action can split the bit or finish off the recess.

Push hard and turn slow. Most of the work in steps 1 and 2 comes from downward pressure. Keep the driver in line with the screw, lean into it, and turn in short, steady movements rather than one fast pull of the trigger.

What if the screw head sticks out?

If any part of the head is above the surface, you have more options than with a flush or countersunk screw.

• Locking pliers. Clamp them on the outside of the head as tight as they will go and turn. Pan heads, button heads and hex heads give the jaws something to hold. On a countersunk head there is nothing to grab.
• Cut a slot. A rotary tool with a thin cut-off wheel can put a straight slot across the head, which you then turn with a flat-blade screwdriver. Keep the slot shallow enough that the head does not split, and protect the surrounding surface with tape or a scrap of sheet metal.

When do you need a screw extractor?

Use a left-hand drill bit before you reach for an extractor. Drill into the center of the head with the drill in reverse. On a screw that is stripped but not seized, the bit often catches partway in and spins the screw out on its own, and if it doesn't, you have already drilled the pilot hole the extractor needs.

Screw extractor. An extractor is a hardened, reverse-tapered tool that bites harder the more you turn it counterclockwise. Follow the extractor maker's chart for the pilot hole size; a hole that is too big leaves the extractor nothing to grip, and one that is too small invites it to wedge and snap. Turn it with a tap handle or wrench, not a power driver, and stop if it starts to feel springy. A broken extractor is harder than the screw around it, so stopping early is cheaper than drilling out a snapped extractor.

Drill the head off. If the extractor won't move it, drill through the head with a bit about the size of the shank until the head pops off. The part comes free, and you are left with a short stub you can often turn out with locking pliers once the clamp load is gone.

Why won't a stainless steel screw come out even with a good grip?

Sometimes the recess isn't the real problem. If you have a solid grip and the screw still won't turn, the threads may have galled: stainless steel threads can bond to a stainless nut or tapped hole during installation, and more torque will twist the screw off rather than free it. Our article on stainless steel galling covers why that happens and how to cut a galled fastener out. Penetrating oil helps with rusted threads, not galled ones.

Seized threads in a blind tapped hole usually end with drilling the screw out and re-tapping, or fitting a thread repair insert.

How do you stop stripping screws in the first place?

Most stripped heads come from the same few habits.

Use the exact bit. A Phillips bit that is one size small sits on the tips of the recess and climbs out. A worn bit does the same thing. For hex sockets, use a full-length key or bit that bottoms out in the socket, and replace it once its corners are rounded.

Know what cam-out is. Phillips recesses have tapered walls, so under enough torque the bit is pushed back out of the recess. That push-out is called cam-out, and it is what rounds the recess. Hex and Torx recesses have straight walls and don't push the bit out the same way, which is one reason socket drive screws are common where screws are tightened hard or removed often.

Seat the bit fully and keep it in line. Stainless steel is a relatively soft, ductile metal, so a bit that is only half-engaged or tilted deforms the recess quickly. Push the bit all the way in before you start turning, and keep the driver square to the screw.

Slow down and use the clutch. High speed raises the chance of cam-out and heat. Set the driver's clutch low for the first screws, then raise it until the screws seat without the clutch slipping on every one.

Drill the right hole. A screw forced into an undersized pilot hole needs far more torque than the recess was designed to carry. For thin material, our guide to which screw to use for sheet metal covers pilot holes and when a self-drilling point saves you the step. Lubricating stainless threads before assembly, as the galling article describes, also cuts the torque the head has to carry.

Is a hex socket or Phillips head better for avoiding stripping?

For screws you tighten firmly or take out regularly, a hex socket is the more forgiving drive. The straight walls take torque without pushing the key out, and the key or bit is cheap to replace when it wears. The trade-off is that a small hex socket, especially on a low-profile button head, has shallow walls, so an undersized or worn key can still round it out.

Phillips is fine for light-duty assembly where speed matters more than torque, as long as the bit size matches the screw. Slotted heads are the easiest to cut a fresh slot into but the hardest to drive straight with a power tool.

The drive matters less than the habits above. A matched, fully seated bit in any drive will strip far fewer heads than a worn bit in the "right" one.

The bottom line

Work from least damage to most: grip aid, bigger or harder bit, pliers or a new slot, left-hand drill bit, extractor, and finally drilling the head off. If a good grip still won't turn it, suspect galled threads rather than the recess. To strip fewer heads, use an exact-fit bit, seat it fully, keep it in line and slow down.

When you replace the damaged screws, Fastenio's stainless socket head cap screws, button head cap screws and machine screws cover hex and Phillips drives, and the 18-8 vs. 316 guide helps you pick the grade.