Whether you are a bladesmith or have gone to the market to buy a knife, you need to have this knowledge. Knives are made out of different types of steel and for different uses and environments.
These specifics mean that a knife could be good, but it gets damaged quickly because you use it in an environment it was not made for. So let us get deeper in the discussion about steel, specifically, a comparison between CPM 20CV and M390.
CPM 20CV vs. M390
The M390 and CPM 20CV are almost the same steel with minor differences. Both the blades are premium, and they have an almost similar rate of performance. The only difference between the two is their levels of silicone.
M390 has 0.7% silicone in its structure, while CPM 20CV has 0.3%. In addition to this, they have different tempering and crafting requirements which make each unique. In practical use, knives made with one steel can be alternated with the other.
How Well Do The Two Types Of Steel Work?
CPM 20CV tends to have more delicate edges; it can attain more sharpness and cut deeper than M390. They are both heavy-duty metals, but CPM 20CV gives a more precise cut, making it a good choice for delicate tasks.
These two types are almost similar in structure, so they have almost similar performance levels. Both CPM 20CV and M390 steel have a 51-61 HRC hardness depending on the forging quality.
This value makes them heavy-duty, meaning they can handle a lot of pressure without getting deformed. This feature further extends their application in the field from cutlery to hunting and military knives.
CPM 20CV knives and M390 knives both come with increased edge retention and corrosion resistance.
They are made from tough steel that is hard to deform, which means you can use the knives to cut through hard materials and still keep a decent edge.
With corrosion resistance, you can use the knives in a wide range of environments.
Both M390 blades and CPM 20CV knives hold up well in wet environments over a long time. For cooks or hunters, any blade will be a good choice.
When it comes to toughness, these two blades are slightly above average. Toughness refers to how much impact the steel can withstand without chipping, shattering, or cracking.
If the knife is not tough enough, it could lead to serious injury when it breaks during use. With wear and tear, you will see the gradual change in the blade to anticipate it.
This is not the case when a blade is okay one second; it shatters in the next. There is no test to grade the toughness of steel or any metals, so all you have to go with is a track record.
CPM 20CV and M390 blades have a similar toughness to that of 440C steel, which makes them considerably reliable and safe to use.
Both M390 and CPM 20CVbladehave decent edge retention but the hardness and toughness of the blades come at a cost, sharpening.
These blades are notoriously tricky to sharpen, and they need a lot of energy, time, and skill to pull off.
What Are The Best Premium Knife Steels?
There are a lot of premium steels today, and they have almost similar characteristics. The most known are M390, CPM 20CV, S90V, and S110V.
So when looking for a knife, which one of these steel options will work best? Let’s break it down;
20CV and M390 blades will offer you very high edge retention, which will be advantageous if you are not very keen on maintenance.
This feature puts them slightly above the other steels, but it comes with one major issue.
The S90V and S110V blades are easier to sharpen. While their edges might not hold up as well as those of the 20CV and M390, they are much easier to sharpen.
This makes them a good choice for a user that has the time and patience to maintain a knife.
The toughness tends to be decently high in all the premium steels. While some aspects may be compromised, toughness remains high as the hardness varies.
The best blade should be able to withstand all the work you plan to put it through.
It is impossible to get a knife that is easy to sharpen, extremely corrosion-resistant, hard, and rigid. This means that you have to balance the minerals you put in the blade to make some features more prominent than others.
Therefore, the final choice will depend on your requirements. If you want a blade for hard cuts with little maintenance, you can go for a CPM 20CV or M390 blade. Their hardness makes them more suitable for brute force.
If you are leaning towards quality cuts with high maintenance, then D2 or S90V will be good options for you. In the end, proper use, storage, and maintenance will determine how long your knife will last and work.
How To Pick Steel To Make A New Knife
There is a lot of steel in the market. If you are a beginner, you might look at the options available, and you will be overwhelmed by them with no idea where to start.
The long list of numbers and letters will be very confusing to you.
As a beginner, you might not know what steel to start with, the right thickness, length, or width to work with. Picking steel is the basis of the process, and it is key to the success of your entire project.
The wrong choice of steel will make the session tiresome and frustrating for a beginner since some types of steel are more challenging to work with than others.
When planning to forge, the choice becomes more complicated than picking a knife.
The final choice depends on what you plan to do with the steel. A new bladesmith would best keep away from super steels like S90Vs since they will not work well.
They require more heat and delicate handling at the same time, which means you could damage them. It would help if you began with steel that is thin and easy to work with.
This will give you enough space to learn everything you can before moving on to the next level of learning. Another factor is how you plan to treat-heat the steel.
If you have a heat treat oven and are good with it, you can use some lighter steels like D2 or 154CM. If you are limited to home use, your best choice would be 1084 since it is much easier to heat treat than other types of steel.
Suppose you have settled on the type of steel you want to use; you will now need to get the right size. It would help if you had an appropriate length, width, and thickness to make the forging process as smooth as it can be.
If you intend to make small 3 or 4 inch blades, you could go for thick steel like 1095. It will give you a strong blade, but it isn’t easy to work with if you don’t have the right tools for it.
However, it is not a good idea to go with a thick option. Going through very thick still can be done, but it will take a lot of skill, time, and energy.
As a beginner bladesmith, these are resources you might not have, so you should stay on easier targets.
Thinner sheets will be easier to cut and grind to the form you want. As you get more skills, you can upgrade and work with thicker metals to expand your areas of expertise. A thin sheet will also not need overpowered machinery.
You will have to choose between a 4-foot bar and a 5-foot bar when it comes to the length. The size will be determined by the type of steel you buy, and you need to get as much as you need depending on what you need it for.
The width is also dependent on the size of the blade you want to make. A general tip, high carbon steel is a lot cheaper and easier to work on. For beginners, it would be an excellent place to start and build from there.
Conclusion
CPM 20CV and M390 steels are made from almost the same concentration of alloys, the only difference between them being the silicon levels in them. The additional amount of silicon in M390 steel makes it slightly more rigid than CPM 20CV.
Because of their compositional similarities, 20CV and M390 steel have the same physical properties.
They have the same toughness, edge retention, weight, and corrosion resistance. When choosing between the two, the slight difference in hardness is all you should worry about.
The only problem with these blades is how difficult it is to sharpen them. The hardness that makes them such good tools also makes them a problem. Always look for quality, whether you are buying steel to make a knife or buying a knife.
