You can use your knives for many years without breaking them, but eventually, one of them will probably end up with a broken blade. A broken knife blade can be a real inconvenience. Not only is it a sharp object that can easily cause injury, but it’s also a critical tool for many kitchen tasks. It’s not the end of the world, though, because you can fix a broken knife blade easily.
Fortunately, fixing a broken knife blade is usually a relatively easy process. In most cases, you can fix it with just a few simple tools and supplies.
Read on to know how to fix a broken knife blade in just a few minutes.
Knife Blade Damage Types
Before you can fix a broken knife blade, you need to understand the damage that has been done to it. There are three types of knife blade damage:
🚩Rust
Rust is normal for any metal. It results from the metal being exposed to the elements like oxidation. Oxidation is the chemical reaction between metal and oxygen. Over time, rust will eat away at the metal, causing it to weaken and eventually break.
You can easily repair rust in a blade as long as it’s not forming holes or not causing the metal to pit. In most cases, a light coat of oil will do the trick.
🚩Broken tips
A broken knife tip is a common type of knife blade damage. It can occur when the knife is dropped or when it’s being used to cut something hard. A broken tip can be either blunt or sharp, but it needs to be fixed in either case.
🚩Nicks and chips
Jagged irregularities or nicks and chips on a knife’s edge are also common damage to kitchen knives. It is the result when the knife’s blade either makes contact with a hard surface or is used to cut something too tough, like bone. These irregularities can cause the blade to break more easily.
Also, sharpening a blade roughly without honing it after may result in nicks and chips.
Steps To Fix A Broken Knife Blade
Now that you know the different types of knife blade damage, it’s time to learn how to fix a broken knife blade.
🔪Check the broken blade.
The first step to fixing your knife is to analyze the damage. It will make it wise to decide whether you can repair it easily or professional help is required.
If the blade is broken off completely from the knife, it might be difficult to fix it without professional help. In this case, you might want to take it to a knife sharpener. If the blade is only partially broken, you can easily fix it at home.
When the damage is on the blade’s edge, you may want to check if any chips exist and examine if any cracks forming in the steel could lead to a break. You may also need to fix these cracks, aside from the chips.
If the knife damaged its tip, check the break if there are bends or curves. If there are, you will need to straighten it as part of the fixing process.
🔪Determine the type of repair you need to do
Based on the damage, you will need to determine the type of repair that you need to do. After checking the knife for damage, these are the general types of repairs you might need to do.
When you need to fix the knife’s edge, mark along the edge, so you have a guide on how many portions you need to remove to get rid of the chips and nicks. If the rust is only on a small area, you can remove it with a wire brush and some oil.
If the damage is on the knife’s tip, mark the portion of the tip that you will remove to re-build the new tip. In some instances, the best option is to remove some of the knife’s spine towards the blade if it’s severely damaged.
🔪Prepare the tools
Of course, the tool you will need depends on the damage and repair you will do.
Knife tip
- Belt grinder: If you’re going to grind the knife’s tip back into a point, then you will need a belt grinder. It will give you a clean and even break.
- A disc sander: If you do not have a belt grinder, you can use a disc sander to do the same job. Just make sure that the disc is completely flat.
- Dremel: If you’re only going to remove a small amount of material, then you can use a Dremel. It will give you more precision than using a knife.
- Files or Sandpaper: You can use files or sandpaper if you’re not going to remove too much material. Just make sure that the surface is level and smooth before moving on to the next step.
Knife’s edge
- Whetstones: Whetstones are the best option to sharpen a knife’s edge. You will need whetstones in with coarse, medium, and extra-fine grit.
- Honing Guide: If you’re not comfortable sharpening a knife’s edge, you can use a honing guide to help keep the angle consistent.
- Sharpening Steel: A sharpening steel is another option if you don’t have a whetstone. You will need to use steel with the same hardness or harder than your knife.
🔪Fix the knife tip
If you use a disc sander or belt grinder, you will need to hold the knife in place. If you use hand files or a Dremel, you will need to hold the blade with a clamp or vice.
Now that you have the tool and blade in place, it’s time to start fixing the knife.
If you’re using a belt grinder, move the blade towards the grinding wheel at an angle. Apply pressure and move the blade back and forth across the wheel as you grind the tip back into a point. Make sure you’re paying attention to the markings that you made.
After once or twice passes of the tool, check the knife if you are evenly removing the metal. If not, then adjust the angle and make more passes.
If you’re using a disc sander, hold the knife against the disc at a 90-degree angle. Apply pressure and spin the knife around as you sand it. Make sure to keep checking if you’re removing even amounts of material. You can stop if you have already reached the edge of the markings and you have re-built the tip of the knife.
🔪Fix the knife blade edge
If you’re using a whetstone, start with the coarse grit (120 grit is the best option). Then, you will need to soak it in water for 10-15 minutes. Once the whetstone is wet, hold the knife at a 20-degree angle and use gentle pressure as you slide the blade down the stone.
After six to eight strokes:
- Turn the knife on the other side.
- Repeat this process and make sure that you keep the same angle.
- Once you notice the chips are gone and you’re closed to the markings, move on to the medium grit (220 grit).
- Do the same as what you did before and ensure that you’re consistent with the angle.
Finally, use the extra-fine gritstone (400-600 grit) and repeat the process. Ensure that the blade is clean and dry before moving on to the next step.
Start with the coarse grit if you’re using a honing guide. Then, you will need to put honing guide on a flat surface and tighten the screws. Make sure that the blade is snug in the honing guide.
Now, hold the knife at a 20-degree angle and use gentle pressure as you slide the blade down the honing guide. Eventually, turn the knife on the other side. Repeat this process until the chips disappear.
🔪Polish the fixed knife blade
The next step is polishing the knife blade. If you’re working on the knife’s edge, you can finish the edge with a polishing stone to give it an even better edge. Use whetstone with 6000 grit to finish the blade. Make sure that the surface is clean and dry before you start.
If you’re not working on the knife’s tip, it would be best to rub-down the knife’s spine with fine grits of sandpaper. It will remove any burrs, make it smoother, and create a mirror finish.
Why repairing a broken knife necessary?
A knife is a very important tool, and it’s necessary to have it fixed as soon as possible if it’s broken. Not only will it be hard to cut things with a broken blade, but the sharp edge can also be dangerous.
Also, it might not work as well as it did before. By repairing the knife, you’re making sure that it’s safe to use and it will function better. Not only that, but you’re also saving money as you might not have to buy a new knife if your old one is broken.
When can’t you fix a broken knife blade?
There are some cases where the knife blade is too broken, and nothing can fix it. Some instances include:
🤷♂️The blade snapped in half.
When a knife snaps in half, it means that the blade is severely damaged, and it’s not possible to fix it. Although there are some instances where you can salvage it, it won’t longer serve its purpose as a knife. The best option would be to discard the blade and find a new one.
🤷♂️The blade is severely bent or twisted.
If the blade is bent, you can straighten it by using a vise or pliers. However, if the damage is too severe, the blade is not fixable. In this case, you can either use a new knife or discard the old one.
🤷♂️The blade is severely chipped.
If the blade is severely chipped, it can be fixed using a whetstone. However, if the chip is too big, the blade requires a complete change to function as a knife again.
🤷♂️The knife’s blade has cracks.
Tiny cracks in the blade show that it’s weak, and it won’t take much for it to break. If the blade has any cracks, you should stop using the knife and fix it as soon as possible. Although you can use it if you’re careful, it’s not advisable to do so.
🤷♂️The blade is stained.
A stained blade means that the metal is rusting. If the corrosion is not too bad, you can try to clean it with a wire brush. However, if the corrosion is too severe, you should throw away the knife and buy a new one.
How to Avoid Knife from Needing Repair?
Taking care of your knife is important if you want to prevent it from needing repair. By following these tips, you can keep your knife in good condition and prolong its lifespan.
✅Avoid using stone, ceramic, or steel chopping boards.
Using a hard surface to chop or slice food can dull and damage the knife’s blade. It’s best to use a wooden chopping board as it won’t harm the blade. It is also best to use plastic chopping boards since it’s more hygienic and safer to use.
✅Don’t use the knife for anything other than its intended purpose.
Knives are not meant for prying open cans or bottles, so avoid using them for that. Not only will it damage the blade, but it can also be dangerous to do so. Also, you should not use a standard kitchen knife to cut bones and joints, as you must do this with a cleaver or boning knife.
Different types of knives are designed for different purposes. It’s important to use the correct knife for the job to prevent it from being damaged.
✅Don’t leave the knife in the sink.
Leaving the knife in the sink will cause it to rust and corrode. Even though most knives are made of stainless steel, it’s still not advisable to do so. The chromium element of the stainless steel will cause the knives to deteriorate when soaked frequently. If you’re not going to use the knife, make sure to wash it and dry it off.
Additionally, don’t wash it together with the other utensils. It will cause scraping and knocking against other cutlery, making the knife dull and damaging the edges.
✅Store the knife properly
When you’re not using the knife, make sure to store it in a safe place. Don’t leave it lying around or put it in a drawer with other sharp objects. You can store it in a knife block, magnetic strip, or sheath.
✅Avoid washing it with a dishwasher.
Although it is possible to wash the knife with a dishwasher, it’s not advisable. The high-pressure jets of water can damage the blade and make it blunt. Knives with wooden handles should not be washed in a dishwasher, as the water will cause the wood to swell and split. It’s best to hand-wash the knife using mild soap and warm water.
✅Hone the knife regularly.
Regular sharpening of the knife will help to keep it in good condition. You can use a honing rod, sharpening stone, or diamond sharpener to do this. If you don’t have any of these, you can use a metal kitchen spoon. Simply hold the knife at a 20-degree angle and rub the blade against the spoon. It will help to realign the blade and remove any nicks.
✅Don’t scrape it across the cutting board.
Don’t scrape the knife across the cutting board when you’re slicing food. It will damage the blade and cause it to become blunt. Instead, use a slicing motion to cut the food. Avoid scraping the ingredients with the edge as well. It might be a habit for many, but it’s not advisable to do so as it will dull the knife.
It would be best just to pick up the food or move them on your cutting board. You can also use the dull side or back of the edge to scrape the ingredients.
✅Don’t over sharpen the knife.
It’s important not to sharpen the knife extremely as this can also damage the blade. When you’re sharpening the knife, make sure to use light strokes and only do it a few times. If you sharpen it too much, it will cause the metal to become too thin and brittle.
Frequently Asked Questions
Q: How can I tell if my knife requires repair?
A: You can lookout for a few things to determine if the knife needs repairing. These include nicks and chips in the blade, dullness, and rusting.
Q: Why is my kitchen knife’s blade chipping?
A: There can be a few reasons why the kitchen knife’s blade is chipping. One of the reasons might be that you’re using the knife for tasks it’s not meant for. For example, you use a cleaver to cut through bones and joints. Another reason might be that you’re not properly taking care of the knife – washing it with a dishwasher, leaving it lying around, etc. Finally, it might also be that the blade is defective and needs to be replaced.
Q: What can I do if my kitchen knife’s blade has rusted?
A: If the kitchen knife’s blade has rusted, you can try to clean it off using a wire brush. If this doesn’t work, you can take it to a professional who will fix it for you.
Q: How to fix a carbon steel knife’s blade?
A: If the carbon steel knife’s blade is dull or chipped, then you can try to sharpen it using a honing rod, sharpening stone, or diamond sharpener. Try following the steps above. If this doesn’t work, then you might need to take it to a professional who can fix it for you.
Q: How can I straighten a knife tip?
A: If the knife tip is crooked, heat the steel to around 400 degrees Fahrenheit using a blowtorch. Bend the knife so that the tip is in the desired position and quench it in oil. Repeat this process until the desired results are achieved. If done correctly, the knife will be straighter and harder than before.
Final Thoughts
Having a broken knife may seem like a big inconvenience, but with a bit of know-how, you can fix it yourself and be slicing and dicing in no time. The tools and fixing you need depend on the kind of damage the blade has sustained.
However, by following the tips and advice in this article, you’ll be on your way to fixing that pesky kitchen knife in no time.