A hex wrench is an indispensable tool for repair work. Hex keys are divided into internal hex keys and external hex keys. The internal hex key is usually L-shaped with a 90° turn.
The curved end is long and other end is short. When screwing with short side, holding long side can save a lot of effort and fix screw better. The long end has a round head and a flat head. The round head is easy to insert and disassemble obliquely, and some parts that are inconvenient to use with a wrench can also be installed.
The main features of hex key:
Simple and lightweight, there are six contact surfaces between hexagon socket screw and wrench, which are fully loaded and not easy to damage; they can be used to drive a screw into a deep hole. ; The diameter and length of wrench determine torque; it can be used to tighten very small screws; both ends of key can be used.
The types of external hex keys are more diverse. Compared with internal hex key, production cost of external hex key is much lower.
If you want to buy a wrench in near future, it is recommended to pay attention to these three when buying a wrench.
1. Based on material, most wrenches are made of high strength carbon steel, but quality of wrenches on market varies greatly, so care should be taken when purchasing.
2. Look at torque and stiffness. The key mainly uses force to loosen bolt, so torque and hardness of key are very important indicators, and their quality directly affects life of key.
3. Look at tolerance range. If you want to choose a fixed key, you should choose a smaller tolerance range so that screws can be easily unscrewed. In general, tolerance range error of keys produced by common brands is very small, so it is recommended to buy brand products directly.
The above is internal hex key and external hex key, and how to choose key. I hope you find it useful.