The beauty of knife making lies in the fact that you don’t need to spend a lot of money on materials. Moreover, you can get it for only a couple of bucks or sometimes even free.
One of the most popular materials used for making a knife is steel from a file.
Do Files Make Good Knives?
Files are an excellent material for making high-quality knives. It is mostly made from high-carbon steels like 1095 and W1, which allows it to withstand heat-treating. Also, a file doesn’t require a lot of shaping, which makes it easier to make a knife out of it.
What Steel Are Files Made From?
Files are typically made from carbon (1%-1.5%), manganese, chromium, tungsten, and vanadium. That mix of alloying elements will produce a good knife blade.
Keep in mind that not all files have the same mix of steel and every file will react differently when forged into a knife.
Next, we will talk more about its properties, usage in knife making, and how to see whether you have a good or bad-quality file.
How to Know Whether You Have a Good or Low-Quality File?
As with most tools, you simply don’t always know what it contains. Also, this is a very subjective topic as we don’t know what worked for some people and what isn’t. When it comes to files, two of the most popular brands are Nicholson and Simmonds.
While there may be some more of them, these 2 are the most known for their quality products. Now, the never files are generally much cheaper to produce due to their inferior mechanical properties. Note that, I am not saying that all of the new files are bad for making a knife, rather this is a gradually undergoing manufacturing process.
While both of these brands still make good-quality products, your best chance is to find some older files due to their hardening ability. If you want to be more secure with a good-quality file, we recommend using an older file for knife making. With them, you are more likely to make a good heat-treating and therefore, get a nice knife out of it.
Another thing to keep in mind is to notice whether that file has some identification like the name of the company, country of origin, etc. If it doesn’t, this is usually a sign of a low-quality file, so it is a gamble to make a knife out of it.
In case it has some identification of where it is made from, and it says China, India, Taiwan, or some other lower-cost producing area, it is probably not the ideal file you want to use.
Now, to test your file, one of the best ways to do that is to heat-treat it and make a file test afterward. What you first want to do is to anneal the working material to make it soft. One tip for annealing the file: grind the edge on the tip of the file so your material is not affected by case hardening.
After that, you can simply quench it with oil. Some of the best quenching oils are Parks AAA, Parks 50, and Canola Oil.
To learn more about quenching oil, check What Is the Best Quenching Oil?
After your file has been heat-treated, it is ready for a file test. File test is extremely easy to perform, unlike other tests, this one doesn’t require expensive equipment. All you need is a file, working material (in this case a file), and a vise.
You start by clamping your material in the vise. Now, take the file and make about 5 strokes on the edges of your working material. This way you will find out how hard is the material and whether you can properly harden it.
1095 and W1-Most Used Steels for Making Files
Steel comes in many different forms due to the variety of functions it can serve. It is mixed with many different alloying elements to provide different purposes. One thing that all steels have in common is carbon. It can be found in varying percentages, depending on the usage of that particular steel.
The most commonly used steels for making files are 1095 and W1 steel. While there may be more of them, these 2 stand out.
1095 Steel is one of the most popular carbon steels used for various kinds of blades. It has 0.9-1.0% of carbon content, depending on the manufacturer. This high amount of carbon content makes this steel excellent for the hardening process. 1095 is extremely durable, meaning it can reduce the amount of wear that a knife will be exposed to over time.
Due to its low levels of manganese, it is not as tough as other forms of steel, despite its high amount of carbon. It holds edges exceptionally well and it is so easy to sharpen. On the other hand, if not oiled, 1095 Steel can easily rust, mainly due to its mechanical properties. So keep in mind to oil it and take the required care to prevent rusting.
Proper care includes rinsing it off after each use, oiling the knife at least once a week, and wiping it clean. 1095 Steel is a recommended steel for beginner knife makers, mainly because of its simple heat treatment.
Just because some steel is good for making knives, that doesn’t necessarily mean that it is good for every type of knife. The same principle applies to this steel. Namely, 1095 is not recommended for making various tools and sushi or folding knives.
This is primarily due to its brittleness. Even if it is easy to sharpen, 1095 has a tendency to crack if the blade isn’t thick enough. Be careful when you heat treat the 1095 Steel as it can get brittle if you go beyond that point.
Although this steel does shine, it doesn’t shine like other stainless steel. Even if it doesn’t contain chromium, it can be polished very easily. To find more information about the properties of this steel, you can check it here.
W1 Steel is the second most common steel used to make files. It is considered a water-hardening tool steel, hence, the letter “W”.
Water-hardening steels consist of 3 types, W1, W2, and W3. Each type has slightly different mechanical properties but the common alloying element is carbon.
In some types, chromium is added to increase the hardenability and wear resistance. W1 is known for its toughness. This is mainly due to the vanadium content that W1 has. It is the most commonly available water-hardening steel. As its name suggests, it is quenched in water, however, it can undergo some level of cracking and distortion during the quenching process.
We had a more successful experience with 1095 than with W1 Steel, especially with the heat-treating part. The other time when we heat-treated the W1 Steel, we had cases of cracking and warping several times, but the best and the only way to find out is to try it for yourself.
In our case, W1 got harder than 1095 Steel but it was more brittle if we left it that way. While both of these steels are excellent materials for making knives, 1095 is a little more forgiving in the heat-treating process. If you are a beginner, we recommend skipping W1 Steel and using 1095 instead.
Do I Have to Soften the File to Make a Knife Out of It?
You can only work with materials that are softer than working tools. While files are hardened, they need to be softer, so they can be worked with other tools, like hacksaws and other files. To soften the file, part of heat treatment is done, called annealing.
It is a heat-treating process used primarily for increasing the ductility and reducing the hardness of the material. Reduction of dislocation in the crystal microstructure during the annealing process changes the hardness of a metal. It is mostly done if the material has been previously hardened.
To properly anneal the file, it has to be heated somewhere between 1350-1450°F (732-787°C). You will know that you achieved this temperature by doing a magnet test. If a magnet stops sticking to a file, it is time for cooling in the air until the red color is gone. In case you can tell whether it is red or not, try to lower the lights, it will help.
Using a heat-treating oven will give you a much more precise result and will fully anneal the file. If you don’t have one, you can use a torch. While using a torch usually requires more skills, it is more accessible for most people.
Sometimes, air cooling can be too fast for the metals, so keep in mind that you have a few more options like using dry sand, vermiculite, and an insulating blanket. Both dry sand and vermiculite will do the job as long as they are dry. A combination of glowing metal and moist is not a desirable result as it will speed up the cooling process, rather than retain the heat.
Using an insulating blanket is more convenient because there is less possibility to make a mistake. We found that blankets for chimneys are excellent for this purpose, so give them a try.
