Paint Polishing Techniques
Posted by: AutoRefinishSupply.com in Autobody and Paintwork, Tips, tags: buffing, color sanding, paint polishingColor sanding/Polishing steps: 1. Assess the damage, or imperfection 2. Choose correct sandpaper 3. Choose correct compound, polish, and pads.
Not all automotive finishes are exactly the same. With that in mind choosing the correct color sanding technique and polishing compounds are necessary to achieve the best finish possible for your vehicle.
Most original finishes are applied very thin at the factory making it very diffcult to color sand and polish without making the mistake of “burning through” the finish. Color sanding should only be done on an original finish when absolutely necessary (when a surface scratch appears or in extreme cases of water spot damage for instance) and by an experienced technician.
Assessing the damage or imperfection on a paint finish is relatively easy for anyone. it is usually the first thing a customer will see on their new paint job, no matter how good everything else looks that small run, dust particle or scratch is the first thing they will see, and when they are paying the current rates for a paint job, it has to be fixed. How deep a scratch is, how heavy a run is, or how large or small the dust particle is will help you to determine the grit or courseness of sand paper you will begin with.
Choosing the correct sandpaper to begin depends on the existing finish. Deep scratches will need to be sanded out meaning you will have to go at least as deep as the scratch for it to be unnoticeable in the finished product. That does not mean you will begin with a heavy grade sandpaper such as 150 or 220! In most repair applications 1000, 1500, 2000 grit sandpapers, are the most popular weapons, in some cases papers as heavy as 800 used with some runs, and as fine as 3000 for ultimate perfectionists, will be used. Experience will be your best friend when choosing paper, but if you are not familiar with the technique begin with finer paper. Sanding should be done with clean slightly soapy water, this will help flush sanding particles out of the paper and also create a smoother sanding rythm. Example color sand routine: begin sanding with 1500 grit in one direction and “crosscut” in the opposite direction until the imperfection is almost gone. I say almost gone because compounding and polishing will cut away the final bit of flaw, if you sand too deep theres no going back, every tech has run into this problem at least once.
Compounding and polishing are very important steps, and can make or break a paint finish. Compounding/Polishing pads include wool, and foam and come in a variety of aggressiveness and styles, velcro pads seem to be the most popular becuse they are easier to change. Wool pads are generally a rougher “cut” pad most techs will begin the compounding procedure with this style of pad. Foam pads can be manufactured to have a very fine finish and are usually selected for polishing or finishing. Rough or aggresive compounds are generally used in extreme cases or for older cars that have high amounts of oxidation. Medium cut or fine cut compounds are usually the starting material for most cases. Work one area at a time about a two foot by two foot section, keep the area damp with the material and let the buffing machine do the work, dont force the machine on the surface this could create “burn through”, and watch the corners and sharp edges. Use the compound until the sand scratches gone. Polish the surface with the same technique with a finer pad (usually soft foam) and fine finishing polish. Dark cars are very tough to get perfect because of swirl marks, many manufacturers make products specific to dark colors.
Following these steps will help guide you to better vehicle finish. In the end you are the one doing the job so do it your way. You may find a technique that works for you that some may call crazy but if it works, it works. Experience will ultimately get you the best job possible. Good luck.





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