Most pocket knives that “won’t close” aren’t broken at all: the lock is doing its job, and it has to be released before the blade will fold. Push the liner or frame bar sideways, press the bar on the spine, or slide the button, depending on the lock (each one is explained below). If the lock releases and the blade still sticks, the cause is almost always dirt, rust or a dry pivot, and you can fix all three at home.
Pocket knives are some of the best gadgets you can carry around with you. They might save you a lot of time and trouble, especially in emergencies. Pocket knives can serve multiple purposes, and they can come in really handy.
However, even the high quality ones tend to sometimes fail. Regardless of how often you use your pocket knife, it still might malfunction at some point. One of the most troubling issues with pocket knives is when they get stuck in an open position. So, if you have trouble figuring out how to fix a pocket knife that won’t close, stay with us. We’ve created a guide that will help you assess the problem without any knowledge in knife mechanism repairs.
But, first, let’s go over the basics, so that you can start learning what you need in order to fix a pocket knife that won’t close.
What you’ll need
Pocket knives can come from different brands and they have different types and forms. However, the general rule is that any pocket knife can stop working properly, and won’t close. If your knife is stuck in the open position, in order to start fixing it, make sure to have these things around:
- Well-lit room: pocket knives can have tiny parts and handling them will require nice visibility
- Screwdriver or Torx driver that fits your knife’s screws
- Compressed air or a blow dryer on the cool setting
- A toothpick or a needle
- A table
- Cloth
- A light oil for the pivot
- White vinegar (only for rust)
If you want to read more of our articles about outdoor knives have a look at our guide on backpacking knives or our guide about using a butterfly knife.
Starting off
Sit at a table and place the knife on it. Take a closer look at the knife to inspect it. Try opening it and closing it to see at which point it gets stuck. Find where the locking mechanism of your knife is and make sure you are releasing it the right way (see the lock section below). Keep your fingers out of the blade’s path while you close it.
Only take the knife apart if you have to. Some makers void the warranty if you open the handle, so check that first, and if you do open it, lay the parts out in order so you remember where they all go.
After you’ve done this, there are several possible outcomes:
Outcome 1: Something is stuck in the mechanism
If after closer inspection you notice that your pocket knife won’t close due to something being stuck in it (sometimes even debris, sand or lint) you’ll easily repair the issue and have your knife back to normal. For instance try using compressed air to blow away all debris. If this proves ineffective and the debris remains in the locking mechanism, use a toothpick or a needle to carefully pick the debris from the mechanism. Warm soapy water and a soft brush loosen dried food or sap; dry the knife fully afterward.
After you’ve done this, put one or two drops of oil on the pivot, work the blade open and closed a few times, and wipe off the excess. Too much oil collects dust and brings the problem back.
A small bottle of a light, food-safe oil covers both jobs, the pivot and a thin coat on the blade. Super Lube’s synthetic oil, for example, is sold as NSF rated and food grade, which matters if your pocket knife also cuts food.
Outcome 2: Mechanism is rusty
If the mechanism is made from low-quality material and you haven’t used the unit for a longer period of time, it can be possible that it simply got rusty. Start with a few drops of oil on the pivot and lock and work the blade gently; light rust often frees up this way.
If it doesn’t, soak only the metal parts of your pocket knife in plain white vinegar. Don’t add baking soda: it neutralizes the vinegar, so the mix fizzes and then does nothing to the rust. Keep wood, bone and other natural handles out of the vinegar. Check every 30 minutes and take it out within a few hours, as acid will also etch and darken the blade if you leave it too long. Scrub the loosened rust off with a soft brush.
Rinse, then make sure to dry the whole knife using a towel or a cloth, or a blow-dryer for the internal parts. Next, oil the pivot and give the blade a thin coat of oil. My guide on removing rust from stainless steel knives has more methods.
Outcome 3: You opened the unit up, and still can’t find the reason for the malfunction
If you opened the pocket knife apart and you still can’t find the source of the problem, you might need to take it to a professional. Many knife makers repair their own knives under warranty, so contact the maker first. Otherwise, a knife shop or a custom knifemaker can usually help. More importantly, they have the proper equipment for handling the small internal components of pocket knives. So, if you want to play it safe, this is your best option, and a bent blade or a worn lock is a job for them anyway.
Why don’t you check our reviews about the best flipper knives under $50 or the best knife makers.
So, how do locking mechanisms work?
Locking mechanisms are basically designs in the internal parts of the pocket knives to keep them locked in the open position. However, the things around locking mechanisms become complicated due to the fact that different manufacturers provide different techniques. Knowing yours tells you how to release it.
For instance, we have back locks (lockbacks). A spring-loaded bar runs along the spine of the handle, and its hook drops into a notch in the blade when you open it. To close the knife, press the exposed part of the bar on the spine (usually near the back of the handle) and fold the blade.
Also, we have button locks. A plunger or button on the handle holds the blade open. To close the knife, press the button and let the blade swing shut. Bar-style locks such as an axis lock work the same way: pull the small bar back on both sides and fold the blade.
Frame locks are another option. As the name suggests, part of the handle frame itself is cut into a lock bar. When you open the knife, the lock bar springs inward and sits behind the tang. To close it, push the bar sideways toward the handle edge with your thumb, then fold the blade past your thumb.
Lastly, we have liner locks, which work like frame locks. The difference is that the springy bar is a thin metal liner inside the handle instead of the frame itself. Push it aside and fold the blade the same way. If the liner sits very far across the tang, the lock has worn or the knife needs adjusting, which is a job for the maker. My guide to folding knife lock types covers every lock in more detail.
Conclusion
All in all, if you have trouble finding out how to fix a pocket knife that won’t close, you are probably furious and angry. But you don’t have to be. Release the lock the right way first, then clean, free up and oil the mechanism, and if you can’t do it, it is ok to ask for professional help. We know that even the best knives can sometimes malfunction, but to prevent this from happening, we’d advise ensuring that your knife gets the proper maintenance, starting with cleaning your pocket knife regularly.
If your old knife is past saving, my guides to the best folding knives under $100 and the best OTF knives under $100 are good places to find a replacement.
Gary Portman founded knivesadvice.com in 2019. He learned to cook in his family’s kitchen as a kid and has used kitchen, pocket and outdoor knives ever since, from paring and fillet knives to survival blades he carries camping and hiking. He writes the site’s buying guides, brand reviews and sharpening how-tos to help readers find the right knife for the job. More about Gary.