Judging by the numerous reviews, starting to perform any work, home craftsmen often encounter one problem - the magnetization of tools. According to experts, this property of the metal in some cases significantly helps in the work, because the tools are getting better. For example, using a magnetized screwdriver, it is much easier to screw the screws in the most inaccessible places.
But many are also interested in the reverse side of the issue. How to demagnetize magnetized metal? This interest is due to the fact that in some cases magnetization is undesirable. A caliper with metal shavings adhering to it is unlikely to perform high-quality marking. It is also inconvenient to use a magnetized cutter. These tools as a result of exposure to them with a magnet noticeably reduce the working properties. Information on how to demagnetize metal at home can be found in this article.
What is the reason for magnetization?
Before you are interested in how to demagnetize a metal, you should understand the nature of this phenomenon. According to experts, magnetization is carried out by paramagnets, diamagnets and ferromagnets. Products based on alloys of iron, nickel and cobalt have their own magnetic field, which is higher than the external. Tools are magnetized if they work near electric motors or other emitters. As a result, they will take away part of the magnetic properties.
On the use of magnetized instruments
According to experts, some instruments intentionally magnetize. Mostly these are screwdrivers that are used during the repair of mobile phones, computers and various household appliances. Such screwdrivers will become indispensable in those situations when you need to tighten the screw, but there is no way to support it with your hands.
It is better not to subject watch instruments to the magnetization procedure, since this can stop their working mechanisms. It is undesirable to work with a magnetized drill or cutter, since small metal particles, having stuck to the working part of the tool, will cause a lot of trouble for the master. Read how to demagnetize metal.
About the special device
Especially for this purpose, there are magnetometers, through which the instrument can both give a magnetic charge, and remove it. For someone who does not know how to demagnetize metal, experts recommend the following:
- First you need to determine with what voltage the magnetic field. This is a very important aspect, since an error can lead to the opposite result.
- You also need to measure the voltage on the magnet. It must have the opposite sign.
After these actions, the instrument should be touched by the magnetometer area, as a result of which the latter will be demagnetized.
How to check?
According to experts, all the work will take no more than 10 seconds. To test the performance, the magnetized metal must be brought to the self-tapping screw. Thus, the master will see at what level of magnetization the instrument is located. If the result is unsatisfactory, the procedure should be repeated and then checked again.
How to demagnetize a metal using an electric motor?
First, the home craftsman should acquire a low-power asynchronous unit. In this case, the alternating magnetic field will decrease the magnetization. Before proceeding, the rotor must be removed in the electric motor. If magnetization is required to be removed from tweezers or a drill, then these products need only be introduced into the stator for half a minute. If the stator windings are disconnected from the power supply, the rotation of the magnetic floor will gradually fade away. According to experts, the remnants of the magnetization of the instrument will be so small that small metal chips can no longer stick to them.
Alternative option
Judging by the numerous reviews, not everyone has the opportunity to get a low-power asynchronous electric motor. For such craftsmen who do not know how to demagnetize metal at home, experts advise using a step-down transformer field. There should be an air gap inside its core. It is half a minute and it is necessary to introduce a magnetized instrument. It happens that the procedure does not give a result. In this case, it should be repeated.
With a magnet
Often beginners are interested in how to magnetize a metal with a magnet. To cope with this work is not difficult. The master should acquire an ordinary, but rather large magnet, preferably a rounded shape. Similar products are available in the speakers. Next, over the surface of the magnet spend a drill, tweezers or scissors. It can also be any other metal tool. The distance from the product to the magnet should be kept to a minimum.
About working with large batches of parts
There are times when it is necessary to remove the magnetization from many metal products. This is possible through the desired temperature. How to demagnetize metal by heating? According to experts, for this you will need to warm up the product to a certain state, which is also called the Curie point. Iron is heated to a temperature of 768 degrees. A ferromagnet will need a range higher. Upon reaching the desired temperature threshold, spontaneous magnetized domains are formed.
The process is as follows. Initially, one detail is brought to the Curie point. Then it should be cooled. It is important that in this case external magnetic fields do not influence it (the only exception is the Earth’s magnetic field). Next, using a sensitive induction meter, the maximum magnetization is estimated. Further, in the control zone at a distance of no more than 2 cm from the part, a range of different values obtained by the MF-23 or MF-23M indicator is measured. Magnetic induction should be +/- 2 mT.
About a homemade device for demagnetization
Judging by the numerous reviews, tunnel devices can be used for this purpose. The design of such a device has a coil connected to the mains. There is a hole inside the coil where the workpiece should be introduced. Demagnetization can be successfully performed using a homemade electromagnet. It is not difficult to make it from some materials and improvised means.
The principle of operation is to control the current. Magnetization is carried out by a constant voltage, and by alternating - the opposite effect. Coils are made from old TVs. It is enough to disassemble it and remove the demagnetization loop in the kinescope. Then it folds at least two times. It all depends on what diameter the craftsman needs.
It happens that one loop is not enough. In this case, it can be supplemented from another old TV. Further, the design is equipped with a fuse button, due to which uninterrupted operation will be ensured. The device, designed for 220 volts, is suitable for continuous use, and 110-volt - for short-term connections. If the product is 12 V, then experts recommend using a transformer. With such a home-made mechanism, even dimensional parts can be successfully demagnetized.
A picture tube from a television is by no means the only option for a home master. Judging by the reviews, good products come from old bobbin players. The workpiece should be placed near the product.