Achieving a uniform colour match across the panel is the key to a high quality spray paint finish. However, this isn’t always easy to achieve. A number of factors can make the paint appear as a different colour on different parts of the face. Insufficient overlap, inadequate base coat coverage or excessive pressure can all affect the quality and appearance of the final finish.
However, by using the right application techniques, it is possible to achieve a perfect colour match with every vehicle paint job.
1) Ensure Your Spray Room and Paints Are Correctly Set Up
Before you begin, take the time to make sure you have everything you need and that all aspects of your paint and environment are in place. This reduces the chance of an uneven finish and makes the process quicker.
A lot will depend on your model of spray gun and the paints you are using, so be sure to check your technical data sheets thoroughly.
To set up the right environment, make sure your spray room is at the correct temperature and humidity. This will encourage your metallic base paints to adhere evenly to the panel. You may have to adjust your environmental controls to compensate for outside weather conditions.
For the paints; make sure they are mixed to the right viscosity and ratio before you begin.
2) De-grease The Paint Surface
This helps prevent any irregularities in the paint finish when the base coat is applied. Use a wipe on/wipe off method with two degreasing cloths to reduce the contamination risk.
3) Applying the Primer
With attention paid to the right pressure and coverage, you should only need one coat of wet-on-wet primer paint. To avoid dry areas, keep the coverage to around 50:50. Attention to detail at this stage will ensure a smooth surface and reduce the need for flattening down after you’ve finished.
4) Applying the Basecoats
Double check your technical data sheets and give the paint a good stir so all the components are mixed together thoroughly. Mix the base coat together with a thinner as per the details given on the product technical data sheet. This reduces the risk of patchiness and helps enhance the final finish. For the first coat, the best results come from using a low pressure spray gun to apply a light coat. Don’t go in heavy at the outset.
For the main coat, again apply steady pressure to avoid flooding your panel, but make sure there is full coverage to avoid dry areas. Spray paint the edges first, followed by the face of the panel. Depending on the finish you require, you may need a third coat, followed by mist/drop coat.
5) Applying the Dropcoat
When you apply your mist, or drop coat, you will need to adjust your spray gun to drastically reduce the pressure. Using excessive pressure at this stage will make colour matching difficult, as you may find you have greater coverage on the edges than you do on the face. Slow and steady motion across the panel gets the best results. After this coat, a colour match light is a useful tool to help you detect patches. If you do find colour irregularities, a second drop coat will help even out any patchiness.
6) Applying the Clearcoat
Once the primer and base coat are applied, next comes the clearcoat. The paint should be mixed to the correct ratios before you begin. We recommend following the data sheet carefully and adding thinner if required for extra smooth coverage. This also helps you filter the paint into your gun. Use rapid motions to cover the panel, giving a three-quarter coverage, starting with the edges and moving onto the face. The first coat may have a dry and peeling appearance, but this is no cause for alarm. After leaving the panel for around 15 minutes, come back and apply your second coat of clear, using slower, side to side motion for full coverage.
7) The Final Finish
Environmental factors can affect the final colour finish, so to ensure a perfect colour match, additional work may be needed when the paint is fully dry. If you suspect an imperfect colour match, thoroughly degrease the panel and apply two drop coats through a low-pressure gun to achieve an even final finish.
Watch Our FREE Tutorial Video
For more information about how to achieve the perfect colour match, we have created an in-depth video tutorial that covers all these points in further detail. In the video you will find professional advice about the correct pressures to use for different coats, the best spraying techniques and ratios to use for your paints. Simply click here to access the video.