General Repair Instructions
Before performing any work on the vehicle disconnect the battery terminals.
For safety reasons and for a better quality repair, IT IS FORBIDDEN TO:
- Replace the structural parts of the body without using a repair bench. The use of the bench makes it possible to guarantee the restructuring of the vehicle with the original manufacturing measurements, ensuring the correct positioning of the components that make up the front and the rear part of the vehicle.
- Heat the structural parts of the body to straighten them.
- Cut and weld any bodywork component and reinforcement, edge to edge, on the same line.
Remove the damaged components by cutting them along the joints, following the cutting lines given in the Collision Manual. Correctly carried out, this operation involves a difference of several centimeters between the two cutting lines in order to distribute the fusion spots created by the welding.
The diagram illustrates a possible implementation.
Removing the damaged components is the repair stage during which the most potentially dangerous equipment is used. Before carrying out any operation, carefully read the instruction manual and the safety instructions and warnings given by the manufacturer together with the equipment, and strictly follow all safety precautions.
The use of the following is required for removing damaged panels:
- Power reciprocating/jig saws
- Circular saws
- Pneumatic chisels (only if necessary)
- Plasma cutting systems
- Electric drills
- Milling machines for spot weld removal
- Grinders
- Hammers and dolly blocks
- Disc grinders
- Air extractor fans
Power reciprocating/jig saw- This type of saw makes it possible to make fast, precision cuts with the possibility of regulating the speed of the blade so that it can be adapted to suit different situations.
Vibrating circular saw- A vibrating saw is used in situations which require high precision cutting; for example, the panel in a box section is to be replaced, overlapping on the panel that should not be damaged. By adjusting the speed and the number of oscillations it is possible to achieve the precision required, according to the usage conditions. The high safety level for this instrument means that it is advisable to use it as an alternative to other types of saws.
Pneumatic chisel-
The pneumatic chisel is used to remove pieces of sheet metal. Its use is indicated when:
- It is not possible to use the power saw, the spot weld removal milling machine or the drill (for example, when behind the sheet metal to be cut there is another that must not be damaged)
- It is possible to separate the welded panel directly by inserting the chisel tip between the two panels along the join, in order to leave no edges to be removed at a later stage.
The different tips which can be fitted increase its versatility of use.
Plasma cutting system- This cutting system, produced through the combined effect of an electrical arc and gas or a gas mixture, is used if very large panels have to be removed. Depending on the thickness of the panel and the depth of the cut, the value of the current and flow of gas can be adjusted in accordance with the instruction manual supplied by the manufacturer.
The use of plasma cutting systems requires the use of an extraction system to remove harmful gases and fumes.
Electric drill- Electric drills are normally used in cases where a milling machine cannot be used. The correct use of the drill for removing spot welds, where multiple panels are overlapping is illustrated below. The tip to be used for these operations is identical to the one fitted on the milling machine. The spot weld must be marked using a drift punch, in order to provide support for the centering point, thereby preventing the cutter from slipping and damaging the surrounding area; the cutter should then be pushed until it reaches slightly deeper than the thickness of the panel to be removed (see diagram below).
| 1- Panel to be detached. |
| 2- Box section panel preventing the use of the milling wheel. |
Example of the correct use of a milling tip.
Milling machine (for spot weld removal)-
A milling machine for removing spot welds is used after the panel to be replaced has been cut to allow the removal of the metal off-cuts remaining on the edges of the body.
The milling machine works on the panel, cutting it as far as the panel underneath and insulating the spot weld.
After removing all the spot welds, the piece cut off can be removed using pliers.
A cutting speed of around 1000 rpm should be used to perform the operation.
Adjust the milling depth using the special screw.
Do not drill matching components. If holes have been made accidentally, close them using (MIG) welding. The presence of holes decreases the resistance of the component involved and can also increase penetration by water and corrosive agents.
Dolly block and spoon- These tools are used when panels need to be hammered straight in order to provide a reaction point supporting the panel. The dolly blocks are designed so that they can be adapted to suit the different shapes of the panel and, when the work area permits, they can replace the hammer.
The spoons have the same usage instructions as the dolly blocks, however they are designed so that they can be introduced through openings and restricted spaces into areas that are difficult to reach.
Dolly blocks and spoons are also used to remove distortions from the edge of panels that are not removed, thereby allowing them to be matched with replaced panels, preventing the structure from being weakened.