Tips for Loosening Nuts, Bolts and Screws | Family Handyman

By Dan Stout

Updated on Aug. 21, 2024

Struggling with a stuck screw, bolt, or other fastener? We asked a trio of pros to share their best tips for shaking them loose.

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We’ve all been there: tackling a project that should be simple, except for a single screw or bolt that won’t budge. It’s even worse when the fastener is in a hard-to-reach spot (there’s a reason these are called “knuckle-busters”).

There’s no way to eliminate the existence of stuck fasteners, but we’ve collected a list of tips to make the battle with fasteners a little less aggravating.

There are many tips included on this list, but maybe the most useful is one echoed by all the pros: don’t let frustration get the better of you. Shaylin King of Mr. Rooter Plumbing says the best way to avoid damage to yourself or the work material is to go slowly and ensure you have a firm grip on the fastener. “Taking your time,” he says, “reduces the risk of slipping and damaging the fixture.”

Every one of our experts suggested this as your first step. It’s effective, affordable, applies to most situations, and has very little risk of damage.

When selecting your oil, look at the label! You’ll likely see a difference between rust penetrants and lubricants. Rust penetrants usually include a lubricating element, but not all lubricants are custom-made to fight rust. WD-40 is a great lubricant, for example, but it’s not formulated as a rust penetrant.

“When I want to loosen a fastening that’s well and truly rusted on, my first port of call is a penetrating oil,” says Richard Ala, founder of Six Brothers Contractors.

Our pros recommended WD-40, Deep Creep, and PB Blaster. But no matter what product you use, it has to be combined with another essential ingredient: patience. It takes time for the oil to penetrate and do its job.

Ala applies a generous amount of oil and steps away for about half an hour. If it’s still stuck, he says, “I’ll give it a few taps with a hammer, apply more oil to help it really penetrate, then try again half an hour later.”

In a garage or workshop, you can spray down the fastener with a generous amount of oil. But use discretion when working from home. If you’re trying to loosen a fastener on an item in a carpeted area, for example, be very careful to avoid overspray and prevent any possible drips.

Stuck fasteners typically aren’t dangerous on their own, but sometimes frustration drives us to extreme efforts that can pose hazards. The most common issue is the “knuckle buster” — when you’re giving a stuck bolt all your muscle and a wrench slips or a bolt head snaps off, sending your hand smashing against an unforgiving surface. Always wear gloves and try to orient tool handles so your hands will be clear if a tool slips.

Similarly, pounding on stubborn fasteners with hammers and mallets poses similar dangers. Bits of the hardened metal can break off and go flying. Safety glasses and hearing protection are a must when you’re running noisy power tools.

And if you’re working with a fastener on an electric device? “I can’t stress enough how essential it is to turn the power off before you start loosening anything,” says Bobby Lynn, the Owner and Operator of LiveWire Electrical. “Always double-check that the power is off with a voltage tester. Trust me, dealing with live circuits is a quick way to get yourself electrocuted, and no one wants that. Safety first, always.”

Loosening a fastener without considering technique can cause more problems than it solves. “These methods don’t just make the job easier,” says Lynn, “they also protect me and the electrical system from damage, keeping everything running smoothly and safely.”

An impact driver can work magic on smaller nuts and bolts, as well as screws. “Using an impact driver to loosen stubborn screws is the simplest solution and takes the least effort,” says Ala.

For most DIY projects, an impact driver is the best choice. But for larger nuts and bolts, you’ll need an impact wrench. Often found in auto repair shops, impact wrenches are typically used with six-point, impact-rated sockets. Ordinary sockets can’t handle impact work and may crack or shatter under stress.

When you need to tackle stuck slotted or Phillips screws, use a manual impact driver. Apply penetrating oil to the fastener and allow it to soak in. Then, fit the right driver bit in the end and pound it on the end with a hammer. This shocks the fastener, cracking the rust while also twisting the bit. The result is a one-two punch that can pop stubborn fasteners free.

A manual impact driver is a great choice for harder-to-reach spots where you can’t fit the body of a power impact driver. Don’t have a manual impact driver? You can always try faking it. “If you’re tackling a screw that’s refusing to budge and don’t have an impact driver,” says Ala, “try gently tapping the screwdriver a few times with the hammer as you attempt to turn. Often, that’s enough to free the threads.”

This is all about the force. Fit the closed end of the wrench over the bolt head and try tugging in short pulses instead of a full-throttle pull. (Box-end wrenches work better than sockets on stuck heads because they twist in the same plane as the head rather than being offset by an inch or more. )

If that doesn’t do it, add some force by tapping on the crescent wrench end with a wooden mallet or dead blow hammer.

Dealing with particularly large bolts? A pipe wrench might be your best option, especially if you don’t own a giant set of wrenches or sockets. The long handle and aggressive jaw teeth will loosen the most stubborn bolts. Just make sure you get the jaws tight against the shoulders. Pipe wrenches are also a go-to tool when bolt shoulders have been rounded over.

If you have a stuck nut or bolt that can be replaced, why spend hours trying to tease it loose? “When dealing with stripped or damaged fasteners,” says King, “sometimes the best solution is to cut them off. This can be a quicker and easier solution than struggling to remove an old, stuck fastener.”

Use a reciprocating saw, hacksaw, or rotary tool to cut through the nut or bolt. Then, take the leftovers to the store to match them with new ones.

Sometimes, cutting off the whole fastener isn’t an option. In that case, you may carefully cut into, but not through, the nut. Use a flathead screwdriver or chisel as a pry bar to snap the nut off. Be very careful when doing this to avoid damaging the bolt threads. (Or skip ahead to the next tip and use a nut splitter.)

If you’re dealing with a specialty fastener or bolt stems mounted on a larger material, you mustn’t damage the threads when cutting off the nut. You can do this freehand or simplify things by using a nut splitter.

A nut splitter will crack a nut without damaging the threads of the bolt or stem on which it’s mounted. Slip the ring over the nut and turn the tooth into the nut until it breaks.

Removing rivets is easier than you think. Pick a drill bit that’s a tad larger than the hole in the top of the rivet. Run the drill until the washer head is loose. Then, poke the rest of the rivet out of the hole.

I’ve used this same trick to remove stripped screws. To do that, it’s essential to use a small bit and a steady hand to avoid damaging the female threads.

“Think back to your physics class,” suggests Ala. “The longer the bar, the less pressure you must exert. It’s all about torque. If a standard ratchet doesn’t work, switch to a breaker bar. These are much longer and give you that extra leverage. Go slow to make sure you don’t cause damage that’ll make the job harder.”

A “cheater bar” is only cheating if you enjoy the aggravation of struggling with a stuck bolt. Simply slide a metal pipe over the handle of a wrench. The pipe will add tremendous leverage. It’s like converting your standard wrench into a breaker bar. The downside? It can be hard on tools – possibly even applying enough torque to weaken or even snap them.

“A cheater bar can give you that extra use you need without too much effort,” says Lynn. “Be careful, though— I always make sure to use enough force to get the job done without wrecking the fastener or anything around it, especially when you’re in those delicate electrical spaces.”

We’ve already discussed using a mallet to apply torque to a wrench, but this is a more direct approach—give the fastener a number of rapid taps with a hammer. This technique may sound like brute force, but there’s actually a genuine strategy behind it. Those rapid impacts create tiny cracks in the rust holding the fastener tight.

Apply more rust penetrant at this point, which can seep into the rust more effectively. Give the spray time to work, then come back and try the fastener. Continue to alternate the taps and penetrating oil treatment until you can turn the bolt.

A screw with a stripped head may not be rusted in place, but it can be very difficult to latch on and remove. If the slot of a roundhead screw or bolt is chewed up beyond the hope of gripping it with a screwdriver, file two flat edges on either side of the head. Then, turn the head with an adjustable wrench.

Use a hacksaw or rotary tool to cut a new slot at a right angle to the old one. For big screws, put two blades in your hacksaw side-by-side, and cut a wider slot so you can use a big screwdriver. This is also a great way to get a grip on the head of carriage bolts, which have no slot or flat sides to begin with.

Shaylin King suggests a tool many DIYers may not have tried. Basin wrenches have a long handle and head that’s perfect for getting around nuts on shut-off valves and faucet bolts. “A basin wrench is a great tool for reaching in tight spaces to loosen a nut,” he says. While they’re primarily used by plumbers, they can also be used on any hard-to-reach nut.

A screw extractor will grab just about any threaded fastener and remove it—even if the head has snapped off. It usually comes with a hardened drill bit to drill a hole in the center of your stubborn screw or bolt. Then, you turn the extractor counterclockwise (i.e., with the driver in reverse) into that newly drilled hole. Because of its tapered shape and left-hand thread, the extractor will jam in the hole and then begin to turn out the screw.

I’ve probably gone through a dozen of these time-savers. Not because I’ve worn them out but because I’ve let other workers on the job site borrow them, and they’re so useful that they end up keeping them.

Using heat to loosen a stuck fastener is possible, but our pros suggest only turning to it when all else has failed.

“Heat is an option,” says Ala, “but unless you know what you’re doing, I wouldn’t recommend it. You really can cause more damage than you’re planning.”

Applying heat can expand and loosen a nut (or threaded opening). But you should only use it if the fastener is clear of anything that might catch fire or explode. If you’ve already soaked the fastener with a penetrating oil, clean it completely before you apply heat. And make sure you have your shop fire extinguisher close at hand, just in case.

You can use a propane or MAPP torch, but a less aggressive tool is a heat gun. “If you’ve tried everything and that bolt or screw still won’t budge, a heat gun might be your next best bet,” says Lynn. “Use it to gently expand the metal, but watch out—too much heat can damage other electrical parts, and that’s definitely not what we’re going for here.”

If you opt for a torch, aim the flame at the bolt head or nut, not the surrounding metal. Heat for about 15 seconds, but don’t get it cherry red. Then spray the bolt head with water to cool it quickly. Continue spraying until it no longer steams. The expansion/contraction cracks the rust, so add more penetrating oil and let it soak. (DO NOT apply more flame after spraying with a penetrating oil.) Instead, try to loosen it with one of the other methods on this list.