The spotter's advantage is that the force is applied only to the outside that has been damaged. This makes the task easier. This article will describe the principle of the apparatus, as well as how to make a homemade spotter for body repair.
What is spotter?
Spotter for body repair is a device for contact type welding. The pulse formation of this device occurs due to the discharge in a large capacitor and is valid for a sufficiently short period of time. This time is so short that the paint on the back of the metal is not damaged. An ordinary semiautomatic device does not have this property. Therefore, the spotter has become an indispensable device for repairing the car body.
Features of using the device
Spotter is used for the following purposes:
- body welding;
- straightening the body without disassembling the skin.
When repairing body parts using a welding unit, special fasteners are welded to the part that has undergone deformation. With the help of a reverse hammer, the curved metal is straightened. The spotter can also heat the metal, so the material quickly becomes stiff and shape.
Spotter for body repair has the following positive characteristics:
- High level of performance. Using this unit, you can weld hooks for metal drawing.
- Convenience at operation. If you compare the device with a conventional device, the device is safe, as it does not emit sparks, and the metal remains cold. Moreover, such indispensable attributes of conventional welding as gloves, a mask and special clothes are not required.
- High level of quality. Welding does not leave slag and scale and does not spoil the part, which prevents rusting.
- Profitability. Mounting washers are used several times and are not subject to melting. You save supplies.
These reasons are sufficient to understand how well thought out the design of such a device as a spotter for car body repair.
How to make a spotter from an inverter yourself?
Among the instruments made with one's own hand, a spotter for body repair based on an apparatus for welding is quite common. If the assembly of the unit is carried out not from the apparatus for welding, then in this case it will have a low power indicator.
The spotter from the welding machine does not contain ticks. Therefore, the device is considered to be similar to an electric arc device, where the voltage passes through the car body. One contact is connected to the body, and the rod and nozzle act as the second.
Many are interested in: what is required in order to make a spotter out of the inverter with your own hands?
Spotter, made handicraft, includes two main components:
- inverter for welding;
- thyristor relay.
What do you need?
In order to make a spotter from an inverter with your own hands, you will need:
- thyristor, whose power is 200 volts;
- 12 volt step-down transformer to control the relay using a button;
- relay with a power of 30 amperes;
- bridge based on diodes;
- contact group 220 Volt;
- control button.
With the help of a bridge on diodes, it is connected to the mains. In turn, the thyristor relay is connected to the bridge. The transformer is responsible for supplying the control branch of the thyristor circuit.
Iron for spotter is allocated in the amount of 35-40 square meters. see. On the thyristor, overheating is not observed. They are marked in areas located after the cable. Subject to overheating is a rod based on ferrous metal. Its diameter is 16 mm. It is desirable that it be made of brass.
If we talk about the cable for the spotter, then it is taken with a cross section of 70 square meters. mm, and for a mass and a hammer, a length of 1.7 and 2.1 m will be sufficient. Provide pulsed control of the thyristor (PM-40).
The secondary winding of the transformer is wound with a 6.5 by 4 copper bus in the third winding. You can also replace with aluminum. Two more are added to the secondary winding. Finally, the apparatus must contain an aluminum transformer winding of 250 square meters. mm, which corresponds to five windings with six turns.
What is important to remember?
- More often the handle is made of a glue gun, and the working cable has a heat-insulating layer and a switching wire.
- Remember that when heated, the thermal insulation layer contracts.
- The diode bridge and thyristor can be replaced with triacs.
- Do-it-yourself spotter design must be clearly thought out. It should work correctly regardless of the size and means spent on it.
How to make a spotter from a microwave?
You can make a spotter out of the microwave. The most important component of any such device is a transformer. Finding it in its finished form is difficult. Therefore, it is better to do it yourself. You can take the transformer from the microwave.
To ensure an optimal supply of electricity, it is recommended to take a couple of transformers from microwave ovens. Secondary windings are removed from them and new ones are wound. For this purpose, a wire with a cross-sectional index of 50 mm² or higher is used.
What will be required additionally?
The transformer is not the only part of the spotter. The scheme also includes:
- transformer feeding the equipment control unit;
- bridge on diodes;
- variable resistor.
How to ensure the convenience and safety of work?
For the safety of working with a microwave-based unit, its components should be placed in a neat case that is reliable. It will serve as a guarantor of the protection of electrical parts from mechanical damage and pollution, which contribute to the failure of the unit. The casing from the microwave oven itself can act as a casing.
When placing the electric unit in the housing, it is necessary to fix all the parts in the area, the basis of which is dielectric sheet material. Elements must be distributed evenly over the entire area. This will provide convenience when carrying the unit. In addition, small wheels fixed from below can give mobility to the device.
After fixing the electrical parts, you need to think about other components, the work without which would be impossible. These include:
- electrical cables for connecting the transformer for welding with the electrodes of the device;
- a gun for fixing the electrode of the device;
- device for drawing metal;
- working elements of the unit.
Cable cross section calculation
With a known indicator of the current generated by your home-made unit, the cross-section of the cables that ensure the passage of electricity is determined.
The following rule is taken as a basis: for 10 Amperes of current, 1 mm² of electric cable is taken. The length of the cord suitable for the electrode for welding is also important. It should be minimal. This helps to reduce the loss of electricity.
The gun can be made from a thick sheet of hetinax or textolite. A pair of identical parts is cut out of them. In a special recess made in one of the blanks, a button for turning on and a bracket for fixing the electrode are located.
The electrode can also be made independently. For this purpose, copper rods with a round cross-section or tubes made of bronze or copper are taken, convenient for connecting to a cable supplying current.
On the side of the working part of the electrode, a slot is made to insert the welding washer. If the tube is taken as the basis of the electrode, then its working end is flattened, and only after that a slot is made.
Making a spotter for body repair with your own hands from an old microwave and other unnecessary parts is not so difficult. The main thing is patience and attentiveness.