Auto body repair is a new maintenance project and it quickly occupied a market. This is a highly professional project. In the maintenance process, it is necessary to grasp the technical basis and moreover, it is necessary to combine the characteristics of the car body materials and design the process flow in order to effectively improve the quality of the car body repair. So, how to repair the car door? Do not worry, here we take a look at car door repair method.

[Car Repair] Car door repair method

First, the preparation of the car door repair

Labor insurance supplies. Labor insurance products can guarantee the personal safety of door repair operators at work. The labor insurance products to be worn in operation include masks, goggles, work caps, earmuffs and cotton gloves. Determine the damage area. Check the damage area and use a marker to draw out the damaged area. This way we can better ensure that the repaired area is not too large or too small.

Second, for the damage is not serious door repair

Polish the damaged area. Use a disc grinder to grind the old paint film. Attach the No.80 sandpaper to the grinding head of the disc grinder. Note that the hole of the sandpaper corresponds to the hole of the disc, so that the dust generated by the old paint film will be contained in the vacuum bag when the sandpaper is polished. When grinding, always maintain a tilt angle between the grinding machine and the workpiece surface, and apply pressure on the grinding disc to grind the old paint film as quickly as possible. Note that the depression in the direct damage area is relatively deep, and the disc grinding machine may be used simply. It cannot be thoroughly polished. At this time, it is easier to polish the direct damage zone with a belt-type sander. The belt-type sander can also finish other unpolished surface areas. There is no old paint film on the surface until the area to be repaired.

Use meson machine repair. Using a meson machine, first fasten the ground wire and then try the welding. Because the adjustable parameters of the meson machine are too wide, you must adjust a proper current and proper energization time that are most suitable for the maintenance. This process needs to be adjusted to three. Five times to find the most suitable parameter.

When welding, always follow the principle of partial repair of the body surface should be first, then after the first, after the first small, the first strong after the weak, the first to do tendons tendons principle, (recommended) due to the depth of the indentation and the individual to the meson operation skills The level (refers to the understanding and use of high techniques for pulling down), without violating the principle of operation, is operated flexibly in accordance with changes in the surface repair. The site where the last damage was first drawn (referred to as the zone of indirect injury) is recommended to be drawn straight.

Close the fire. To close the fire, remember that every fire is a last resort and is caused by the increase in the surface area of the board caused by the surface is raised or can be gently pressed by hand, and then release the pressure of the hand and the surface will A phenomenon that bounces freely. At this point it is necessary to use the fire to restore it to its original state. The smaller area of the fire can be quickly cooled using the single-point heating of the electrode and the blow gun to force the surface area back to its original state. It is not easy to close the fire continuously at one point.

Cleaning and inspection. The cleaning of the surface and the inspection of the work, the use of disc grinders to clean the surface, grinding off the surface of the carbon drawing injury, in the use of dust blowing gun to clean the surface of the dust. Use a steel ruler to measure the repair of the surface. The surface that we must fix must not be less than 1mm from the original surface. Must not have a high point. The surface area that we have to repair must be clean and free of dust. The repaired surface area must be free of a bit of carbon. If every one of these flawed situations occurs, it must be repaired as required.

Third, for the repair of the door panel with serious damage in local area

For local areas of the door panel due to corrosion or collision, etc., parts of the door panel (such as corroded holes, etc.) cannot be repaired by the door panel repair machine, and can only be repaired by replacing the panel.

Cutting. Using a plasma cutter or a cutting saw, the door panel to be replaced is partially cut. When cutting, be careful to minimize the cutting range, do not injure other nearby parts, and do not damage the door ribs.

Repair. A plate that can be repaired is made and the plate is welded to the door panel using continuous spot welding using inert gas shield welding. When welding, be careful not to penetrate thoroughly, or to make the weld mark too large. Minimize the heat during welding. Then use a grinding machine to flatten the weld, and no high spots can occur.

Fourth, for the most serious damage to the door repair

When the door damage area is relatively large, if the repair method is used in 3, it is very likely to reduce the performance of the door. Therefore, in this case, it is recommended to replace the entire door skin.

Demolition of old panels. First solder joint separation. The primer, protective layer or other covering can be removed with oxyacetylene flame welding torches, wire brushes, grinding wheels, and the like. If spot welding is still not visible, use a tweezers to open between the two plates so that the spot weld profile appears. Use spot welding cutters to drill off spot welds. Be careful when separating, do not cut the plate under the weld. Attach a steel tape measure to the door frame and measure the distance between the lower edge of the tape and the edge of the outer panel. The distance between the front or rear edge of the panel and the door frame is also measured for later installation. Then use a plasma cutter or cut off the wheel to remove the welded part from the outer panel door frame connection. The fastest way to remove the exterior door panel is to abrade the edge of the flanged flange. Only need to wear off enough metal panel to separate the flange. Do not grind the inner panel parts. Separate the reinforcement bar at the top of the panel (if a reinforcement bar is installed or used). Use a hammer and tweezers to gently loosen the two panels. Use tin scissors to cut any solder joints that cannot be drilled or ground. When the outer panel is free to move, remove the panel. Use a vise clip or pliers to remove the remaining part of the inside flange flange. Grind away any residue of spot welding, brazing, brazing, and rust with a disc wheel.

When removing the outer panel, carefully inspect the inner panel and door frame structure for damage. If necessary, correct or repair the damage of the remaining inner door panel at this time. Use a hammer or top iron to trim the dent on the inner flange. Use a conductive anti-rust primer on any spot weld. Other exposed metal surfaces use rust-proof primers or other rust-proofing methods.