Driver Bit & Socket Steels
© Lincoln’s Tool Chest
When looking to purchase bits or sockets, it helps to have a little knowledge on tool steel types and general uses. Not all tools are created equal. There are some inferior products out there, but confirming the tool you are looking at has the right type of steel needed for the application it is designed for will help ensure you won’t be the one gritting you teeth.
S Tool Steels (Shock-Resisting Steel): This includes S1, S2, S5, S6 and S7 steels. This steel can be used for things such as chisels, hammers, punches, dies mandrels, shear blades as well as driver bits. The numbers do not relate to the toughness of the steel, but rather the composition of the alIoy, as S5 has the highest impact toughness of all the tools steels. In this article we are only concerned with S2, because this is the steel that will serve you well in the following: Screw bits and any ratchet driven tools whether they are for driving screw, allen or torx equipped fasteners. Look on the side of the bit. If you can see “S2” stamped anywhere on the shaft, you can buy and use with confidence. One word of caution, if you are using your bits with an impact driver make sure they are impact rated. Impact bits are often made from different alloys to stand up to the constant impact forces being applied.
Chrome Vanadium: This steel is much more common in the market than it used to be. If you are buying regular sockets, they should be made out of this alloy. Look on each socket and you will see a stamp with a CrV or Cr-V. This steel is very strong and wear resistant. Sockets made out of chrome vanadium will serve you well for years. However, this steel is very hard and can shatter, so stay away from using this with your impact wrenches.
Chrome Molybdenum: This steel is what you should be looking for in an impact socket. This alloy tends to be more malleable than chrome vanadium steel. There are two main benefits to this. The first benefit is that your socket will absorb some of the “shock” from the impact, lessening the possibility of it shattering. The second, is that they won’t tend to damage the anvil on you impact wrench like chrome vanadium will. The anvil is the square piece that receives the socket. Chrome vanadium, due to its hardness, tends to deform the anvil on an impact wrench over time with repeated use.