There is no ultimate everyday tool steel but an array of different tool steels for different tasks. Steel grade standards AISA-SAE umbrellas three popular grades of tool steel O-1, A-2, and D-2.
These general-purpose tool steels can hold their cutting edge at high temperatures (400°). What makes AISA-SAE steels ideal for many applications is that they resist wear and deformation.
Good steel is without a doubt an important step towards a good edge but it comes at a price. In this article, I will attempt to explain the differences between different types of tool steel. So please read on and I will go into the positives and the negatives of different steels for different tools.
Hard Steel vs Soft Steel for Sharp Edges?
If a tool is to do its job, then the steel it is made from must be chosen accordingly. If the steel is too soft, It will blunt quickly but equally if the steel is too hard it will chip or even break. For a tool to be usable the steel chosen for its construction has to have some tensile strength as well and adequate hardness.
What Makes one Tool Steel Better than Another?
No two tool steels are made the same. Some tool manufacturers make their tools from general tool steel stock but others smelt their own. Some tool steels such as 01 are simple alloys (an alloy is a mix of two or more metals) Some tool steels are made Without compromise. This attention to detail will Inevitably add significant cost compared to cheaper tool steel manufacturers such as Chinese imports.
Best tool Steel for Hand Planes
Sheffield O1 carbon tool steel is a superior commercially available steel. This oil quenched hardened Steel is a simple Steel iron alloy which contains 1.1% of manganese. If you were wondering the O refers to the oil quenching method. The manganese aligns the steel to be quenched in oil.
Stanley Bailey no 7 with victor plane irons-600-338What do A and O have to do with Tool Steel
- A, such as A2 tool steel is Air Quenched
- O, such as 01 tool steel is Oil Quenched
Veritas PM-V11 alloy steel
According to Veritas, their new alloy labelled as PM-V11 is a new breed of tool steel. PM-V11 has the behaviour of A2 and 01. The durability of A2 and the low effort sharpening of 01.
Best Tool Steel for Chisels
Chisels like hand plane irons are thicker than other types of blade. Chisels also can benefit from being made from 01 carbon tool steel. I suggest 01 on the basis that it is a good value for capable tool steel and so a practical choice. There are other tool steels, but 01 for most amateurs and professionals is a very good option.
Best tool steel for pocket knives.
Pocket knives unlike chisels and hand plane irons require a little bit more effort to make the best life possible. Unlike chisels and hand planes which have added stiffness such as the cap iron or the tang of a chisel and not forgetting the thickness of the steel. Pocket knives especially folding pocket knives have vulnerable areas. On a folding pocket knife, the joint is a point of particular weakness. My Knife sharpening tutorial
Pocket knives are option abused in the field
Pocket Knives are used for multiple tasks and have to be made with that in mind. An archer would use it to dig out his arrow from a tree. A truly versatile tool and just like the swiss army knife is a must tool to carry but check local laws first.
So which tool steel is best for pocket knives?
Unlike woodworking tool steel pocket knife steels are a massive subject and one that deserves its own article. So I will not go into too much detail as it will dilute this topic. For reference here are some of the steels marketed for knife construction.
CPM-154
Aogami Super Blue
ZDP-189
CPM S30V
S35VN
Elmax
Japanese steel can be expensive and frankly unnecessary for most people who only need a pocket knife for some DIY tools.
Carbone 1095 Steel
This is a great steel for thicker blades such as survival knives. This hard carbon steel is brittle and not the best for thinner blades such as Opinel pocket knives.
What Steel Hardness Should I consider?
This will really depend on the designated purpose of the blade. Some steels contain more carbides making them harder. You might think that having harder steel is best but that depends!
Hard Tool Steel
High carbide steels will hold its edge longer but take longer to sharpen.
Soft Tool Steel
Softer tool steel is easier to sharpen but blunts faster.
Mild steel
Mild steel is too soft for making blades. Mild steel does not sharpen very well and the edge will blunt. Do not confuse softer tool steel with mild steel.
Stainless Tool Steel
What is D2 Tool Steel?
D2 tool steel is a semi-stainless tool steel. D2 has a high carbon percentage which makes it hard but also it has a high chromium content but not high enough to class it as stainless steel. D2 semi-stainless steel resists corrosion but is not corrosion-proof. due to the hardness of the D2 semi-stainless steel, it exists abrasion and where is very well.
What is Stainless Steel?
Stainless steel has to have at least 10% chromium added to the alloy for it to be considered stainless steel. A high percentage of Chromium prevents the iron element from corroding. stainless steel that is used for marine purposes has to have a very high chromium element percentage. chromium is not the only element added to stainless steel. Nickel is also added and unlike other tool steels, less carbon is added.
What Makes Stainless Steel Stainless?
Stainless steel is another complicated topic as element Chromium is added to the Iron and Carbon drastically reducing oxidation. The use of Sandvik 12C27 stainless or inox as Opinel calls it in France. It does not rust easily so for blades that do not get sharpened too often are not rusty when unsheathed.
Stainless Steel for Marine use
The stainless for the purpose of knife construction is not the same as the stainless used in the marine industry. 316, 304 and 303 codes of stainless steel are for seawater applications … The 316 types are used widely in marine applications, but their corrosion resistance is not 100%
Stainless steel can still rust
Stainless steel is just Steel with chromium added. The element Chromium protects the iron from corrosion within the alloy. Cheap stainless steel can still corrode or tarnish because of poor quality or low percentage of Chromium added. It is not unusual to see rust stains on stainless steel especially when subjected to salts.
Stainless vers Carbone Steel
Practically stainless wins hands down as the fact that the blade and its edge is not affected by corrosion. Pulling the knife from its sheath clean without rust is preferred. The only grievance I have when comparing Carbone Tool Steel against Stainless Tool Steel. Is that through my experience Carbone steel provides a better performing edge than the high Chromium Stainless Tool Steel?
420 High Carbon Stainless
A good allrounder stainless steel for gents knives and can also be seen used for constructing hunt knives. One of the great benefits is that 420HC high carbon stainless steel is very easy to sharpen.
Sharpening
All that talk of good tool steels for sharp edges and not a mention of how to sharpen it. So I’ll just touch on it here. Sharpening a tool requires some basic tools for honing a good edge.
My preferred sharpening tools
Have two main sharpeners that I use for sharpening most of my sharp edges.
Norton India Oilstone
This particular Oil stone is a time served favourite tool for sharpening most tools. I use this oil stone for mainly for my hand planes and chisels. With a little practice and a sharpening guide, it is possible to get a very sharp edge on a woodworking tool. As the name suggests this sharpener uses oil as a lubricant and also to keep the stone clean.
DMT Diamond Sharpener
DMT is a brand of good quality diamond sharpeners. There are other good quality diamond sharpeners but also some of the low-cost options are actually quite good too. A Diamond sharpener also needs a lubricant. It is common to use water but some prefer Windex or Windolene I personally make my own lubricant by mixing White Spirit and Engine Oil. I use an oil-based lubricant as I have found that some Diamond sharpeners are prone to rust. I also use oil and not water for my diamond sharpeners as my tools are made from cast iron and are subject to rusting.
I have written a blog on sharpening here
Conclusion on Tool Steel
This is my conclusion on this subject and is subjective. It is clear to me that there is ultimate steel but not without compromise. And no matter how the manufacturer may sell their creation there is nearly always a compromise. Whether the time it takes to sharpen or risk of breakage. So for me, the use of simple tool steels is best due to the cost and practical use.