The Freeze Spray Trick That Helps Loosen Rusty Bolts

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Rusted fasteners, unfortunately, happen just about anywhere. Whether it's under the hood of your car or a plumbing fixture in your basement, having rusty bolts can cause significant delays and frustration, not only making removal incredibly difficult but also leading to hardware potentially breaking off in the hole. While you may occasionally be able to remove rusty bolts with a kitchen essential or some other handy hack, it's hard to replace the specialty products made specifically for these issues. When all else fails (or you just want to skip to the quickest fix possible), reach into your toolbox and grab a can of freeze spray.

Freeze sprays, such as CRC Freeze-Off Super Penetrant, are specialized aerosol products that use a chemical reaction to help remove and break down rust on bolts by rapidly cooling the metal, causing thermal contraction. As the metal shrinks, it loosens the nut-bolt connection and opens more paths for liquid to flow through. The product's penetrating lubricant will seep even deeper into the cracked rust and break the corrosion bond. The bolt can then be safely backed out with a wrench or other tool. This method is preferred, since the combination of rapid cooling and penetrating oil makes removal an (almost) painless process.

While you may have to resort to using a nut splitter for dealing with stubborn rusted bolts, freeze spray is a great alternative because it could preserve the hardware for reuse. Before getting started with any freeze spray product, it's important to take the proper safety precautions. Allow adequate ventilation by opening doors and windows. If needed, wear a mask to avoid inhaling the vapors. Always wear gloves and eye protection to prevent frostbite and skin irritation, and wash your hands thoroughly after using the spray.

For this trick to work, you'll need to start by cleaning the area. Skip the soap and water here — you'll use a dry wire brush to remove any loose rust and dirt from the bolt and nut. This helps leave a clean path for the spray to reach the rusty threads. Next, spray the product directly onto the rusty part of the bolt, which is usually where the bolt meets the nut. For best results, spray for at least 10 seconds or until frost appears on the surface.

Here's where the magic happens: You'll need to let the spray sit on the bolt for one to two minutes to allow it to fully seep into the threads. For really stubborn, seized bolts, you can tap the bolt lightly with a hammer to allow the spray to penetrate deeper into the threads. There are some handy tools for removing rusted bolts without a nut splitter that you could use for the next part, like a long-handled breaker bar to generate more torque. If you don't have one handy, use a wrench to slowly try to loosen the bolt. After this process, if the bolt is moving but not much, try tightening and re-loosening it a few times; this will help break up some of the rust on the threads. For bolts that are extremely rusty, you might need to repeat the whole process a few times to break down the corrosion.