1. Selection of electric drill size: With the increase of electric drill size, its price will also increase. The size of household electric drill is usually 20 mm, which is enough.
2. Selection of additional functions of electric drill: There will be some additional functions in the same type. For example, the indication bit of R in the model can be reversed. Its advantage is that when the positive rotation is not feasible, it can be converted into reversal. The indication drill of E in the model can be adjusted to speed, and can be adjusted to low speed when high speed is not needed.
3. Use choice of electric drill: Take indoor ceiling as an example, the ceiling is made of reinforced concrete. It will take a lot of effort to drill with percussion drill, but this will not happen when drilling with percussion drill. Therefore, percussion drill is suitable for daily use in families, but for perforators, hammer drill should be preferred. When drilling a wall, hammer drill will be more labor-saving than percussion drill. The key lies in the difference of structure and working principle between them. Percussion drill needs constant force to rotate in the process of using. When using hammer drill, only a little force is applied at the beginning to make the bit move forward automatically.