Spot repairs have been the focus of our latest publications due to how interesting this type of work can be for the profitability of the paint store.
So far, we have analyzed the concept and characteristics of spot repairs in order to establish objective criteria to help identify this type of work. We have also mentioned the tools and products needed to perform them, as well as those that can enhance the main purpose of spot repairs.
Therefore, to complete the technical range on this subject, in this third and final publication we detail the work processes that allow spot repair to be carried out.
Are you ready?
Work processes used in spot repairs
The work process used when performing a repair has a direct impact on the profitability of the repair. This means that knowing the different techniques, tools and products makes it possible to execute an efficient and effective work sequence in which wasted time and unforeseen events are minimized, while reducing the time the vehicle spends in the bodyshop.
From the point of view of spot repair, the complete repair process is subdivided into three very specific phases, which are as follows:
- Preparation phase prior to repair.
- Damage repair phase.
- Damage painting phase.
Preparation phase prior to spot repair
The procedural steps to be followed in the pre-spot repair phase are as follows:
- Carry out a precise identification and localization of damage on the affected parts, since the existence of larger average damage, severe damage and/or several minor damages makes the repair a standard type of work because it does not meet the criteria for spot repairs.
Within this damage identification, it is advisable that the person who attends to the customer in the first instance is properly trained in this regard to offer these repair options. An attractive option for the customer may be to offer fixed prices for quick spot repairs.
- Once the damage location corroborates that the work to be performed is classified as spot repair, the work process continues with the analysis of the damaged part to determine the type of painting to be performed: complete or partial. It will also be determined if it is a cut painting or not.
Within spot repair, a complete painting is considered as one in which the application of color and clear coat is applied to the entire part when it is a replacement or when the color is applied only on the repaired patch, applying blending techniques, but the clear coat is applied to the entire affected part. On the contrary, a partial painting is one in which only a part of the damaged part is painted by making the cut on some rib or line (partial painting by section), or by means of blending techniques, both when applying the color and the clear coat.
Regarding the cut painting, it will be considered as such any repair in which the damage is located near the edge of one or more contiguous parts, in which case the choice of the color variant must be extremely precise to avoid changes in shade after refinishing.
- The next step is to choose the color variant that best matches the color of the vehicle. The following criteria must be taken into account:
-Choose the test area of the variants, so that this area is located on a high area of the adjoining parts.
-Clean and polish the selected area to restore the original gloss of the adjacent part. This makes color checking more accurate and reduces the risk of error, whether it is done with color charts or with a spectrophotometer.
-When checking with color charts, observation is made from various angles and in daylight. Furthermore, in the case of metallic colors, the particle size should be checked.
You can learn more about these tools in our publication “Color tools you can’t miss in your bodyshop“.
Spot repair phase
Once the preparation phase has been completed, it is time to repair the damage by adapting the work process to the characteristics of the damage. In this sense, the following cases can be distinguished:
- Replacement of damaged part.
- Surface damage without deformation on parts with original paint.
- Surface damage without deformation on refinished parts and slight damage with slight deformation.
- Slight to medium damage with deformation.
The criteria to be considered for repairing these damages are as follows:
- Sanding of the damage and the putty is carried out with a rotorbital or sanding block and sanding grit appropriate to the extent of the damage. For this purpose, 75 and 150 mm rotorbital and sanding blocks of different sizes and geometries with sanding grains between P-150 and P-400 are used. In the case of using spray gun application primers, the sanding should end in a P-320 grain approximately, while if we use aerosols, it will be necessary to start with finer grains and end in P-400.
- Surface damages on parts with original paints do not require caulking as a general rule, while in those occurred on refinishing parts and when it is about damages that present deformation, caulking is unavoidable. However, in both cases it is necessary to prepare the substrate prior to priming and caulking respectively.¡
- When the damage shows deformation, the repair starts with the dent removal of the sheet metal using cold and/or heat forming techniques. After the forming processes, the paint is removed on the worked area with rotorbital and P-150 grit or with a rotary tool on which a three-dimensional disc of expanded nylon is mounted and then putty, taking into account the need and priming on substrates such as aluminum in order to increase adhesion.
- Before caulking and priming, the surface must be cleaned and degreased.
Spot repair damage painting phase
Finally, the spot repair process ends with the painting of the spot repair by adjusting the work process to the type of painting to be performed, so that these options are given:
- When painting spot repair damage to be replaced, the color and clear coat are applied to the entire part after a wet-on-wet cleaning, degreasing and priming process.
- In the rest of the spot repair damage painting, after refining the damage or the putty and its bordering surface, the affected parts are cleaned, degreased and the vehicle is masked, and then the damage is primed, limiting the application to the maximum at to control the paint consumption and not to lose useful working surface for the blurring.
The primer is then sanded with a P-500 grit and can be refined to P-600 or P-800.
Subsequently, the rest of the piece is shaded depending on the type of painting to be performed: complete or partial.
When the spot repair consists of a complete or partial painting by section, the rest of the piece is matted with a 150 mm rotorbital and P-800 grain or the finest abrasive pad of the abrasive brand. In partial painting by blurring the color and the clear coat, a sufficiently large section of the surface is matted to allow the blending of both paints.
The work process continues with blowing the surface and the vehicle, masking and degreasing.
After that, the color is applied through a blending, applying a sweeping technique (application of the paint from the inside of the patch to the outside), or picking up (application of the color from the outside of the patch to the inside). When working with simple colors (plain, dark metallic, etc.) the sweeping technique is used, while when working with complex colors (silver, champagne metallic, etc.) it is convenient to apply a blender and blend. For this type of work, it is convenient to use the touch-up spray gun.
After the application of the color, the piece is clear coated, taking care that the clear coat goes beyond the color application without extending beyond the shaded area and, immediately, the integrating reducer is applied in the transition area.
Finally, in the case of partial painting by blending the clear coat, the transition zone is polished and buffed to even out the gloss and integrate the application with the rest of the piece.
Spot repair as a way to improve paint bodyshop profitability
Throughout the three articles on spot repairs, we have been able to unravel this concept to discover how they can improve the profitability of the paint store. A profitability that can also be enhanced using certain tools and products and the application of specific work processes.
In short, we can affirm that in the search for efficiency as a way of making the business profitable, spot repair is a revulsive to be considered to achieve this highly valued objective.
This is the end of our series of three posts related to spot repair, and we hope they have been of value to you!
