Features of watch screwdrivers

For maintenance and repair of wrist clocks, wall clocks and other mechanical clocks, it is always necessary to open them. And so you have to use watch screwdrivers. This valuable kind of tool is not well known to the general public. In the article we will tell you about the features of watch screwdrivers.

Screwdrivers from a watch repair kit can help in working not only with chronometers, but also with:

• film cameras;
• medical and sunglasses;
• other things where there are particularly thin mechanical fasteners.

In the manufacture of watch screwdrivers, GOST is used for ordinary screwdrivers. It standardizes both the steel grades used for the blade, and the materials used in the manufacture of handles, and the torque. The tolerances for the perpendicularity of the end and for the symmetry of the groove, as well as the level of roughness (the greatest deviation from a smooth surface) are strictly regulated.

Quite widespread are watch screwdrivers with interchangeable blades. It is recommended to choose products with hardened and blued blades, in the manufacture of which chrome vanadium steel is used. Many delivery kits include 4 blades with a diameter of 1.5 to 3 mm. With their help, fasteners of various formats are easily unscrewed and twisted. In some cases, screwdrivers with a double-sided bit are useful.

Such attachments allow you to work faster and more efficiently without harming fasteners. Bits must be as strong as possible and resistant to wear, which severely limits the range of materials used. Precision equipment is used in the production of these parts. When purchasing a 4-bar screwdriver, the mechanical strength of these parts should be given priority. Chromium-nickel coating is better than chrome in anti-corrosion properties, but also more expensive.

Buying a ready-made kit means a significant expense. Sometimes it includes unnecessary tools that are not really needed. Or, on the contrary, such a delicate device is required that it is not sold in ready-made sets. Very small screwdrivers are made from needles. Not only tailoring needles are suitable, but also those with which household sewing machines are completed. You need to get rid of the sharp edge, because you don't need it anyway. Next, the metal is annealed, systematically heating one of the ends to 900 degrees. Subsequent cooling should be slow. The fact that the heating has reached the required stage is indicated by the orange color of the edge. If it is reddish, the heating should be increased, and when it reaches a light yellow or white tone, it should be weakened.

You can use a conventional gas stove burner to heat the workpiece. It is necessary to cool the needle by carefully pulling it out. At this moment, the plastic qualities of steel will increase, so it will be possible to immediately give the desired shape on a small anvil by blows of a miniature hammer. Suitable anvil:

• the striking part of a larger hammer;
• steel pliers;
• pliers;
• another metal tool with a sufficiently large flat area.

You can improve the forging by reheating the needle.This time, the speed of withdrawal from the flame does not matter anymore. Having given the tip of the workpiece the required shape, it is modified using a flat file. Sometimes they just grind. After finishing the processing, it is imperative to harden the screwdriver blade by heating its end to a dark cherry color and immediately after that dipping it into water.

A part hardened in this way is unnecessarily fragile. You should definitely resort to one more method of processing - the so-called vacation. First of all, the workpiece is heated so that it becomes either purple or light blue (iron acquires these tones in the range of 285-300 degrees). Since the scale on hardened metal will make it more difficult to accurately recognize the colors, it is imperative to remove it. The tempering procedure ends with a gradual cooling of the needle in the air.

In the next video you will find unboxing and an overview of the watch screwdriver set.