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The Auto Painting Tips Newsletter

With Chris Curwen & Expert Auto Painter - Dave Gage (Car Cosmetics)

December 12th, 2007 - Issue 33

In this issue:

  • Special Additives - Used to prevent or eliminate various problems that may present themselves as you paint your vehicle.
  • Your Questions Answered - An update on what's been covered recently.
In your last Auto Painting Tips newsletter we discussed the undercoats classed as primers: Auto Paint Primer, Epoxy Primer and Paint Sealer.

You discovered their proper uses, their individual benefits, how to avoid problems along the way while you use them and more.

Today, we’d like to cover Special Additives with you.

What are Special Additives used for?

There are a variety of special additives available to buy which are used to prevent or eliminate the various problems that may present themselves as you paint your vehicle.

Among such additives are fish eye eliminators, chip resistant coatings and special additives for use on flexible auto body components.

These additives, for the majority of the time, should not be used unless your paint project involves the problems or circumstances they were designed to address.

Fish Eye Eliminators

Firstly, what are Fish Eyes?

Tiny surface finish blemishes that resemble small circles of popped paint bubbles, which appear almost as soon as paint hits an auto body surface, are commonly referred to as fish eyes.

What causes fish eyes to form on the surface?

Fish eye surface blemishes are generally caused by silicone residue. Small traces of silicone does not allow paint to settle evenly, they instead cause material to encircle the speck of silicone and form a volcano-like shape.

The problem of fish eyes is the result of extended use of silicone based vinyl dressings on body side moldings and other trim. An excessive dressing application and random overspray away from trim infiltrates surrounding paint surfaces to become embedded in the finish.

Even though these painted surfaces may be thoroughly cleaned before the application of any paint materials, silicone particles commonly remain and cause fish eye problems.

In more severe cases, silicone materials can be absorbed by paint finishes to such an extent that the underlying metal becomes saturated with silicone, making quality repaint efforts an almost impossible task.

Although there are indeed products available to purchase which prevent fish eye problems, their use is not widely recommended.

The best method for eliminating fish eye problems is...?

The best way to eliminate fish eye problems is to thoroughly wash the entire vehicle before doing any paint prep work.

Indeed, one of the most important things to do prior to sanding, priming or painting is to make sure your vehicle is as clean as it possibly can be.

Prior to doing any bodywork, the affected panels should be thoroughly washed, using a mild car wash soap or even washing up liquid for dishes along with plenty of water.

If you are going to be repainting the entire vehicle a more aggressive cleanser could be used to wash the vehicle with to help eliminate fish eye problems.

Take you time when rinsing too, making sure that you do a thorough job at removing all of the cleaning solution.

Wax and Grease Remover should also be used.

When the surfaces are clean and dry and prior to any sanding of the panels, use wax and grease remover to help remove any other residue. It’s very important to remember that if the sheet metal isn’t clean, body filler, primer and paint are not going to adhere properly.

Fish Eye Eliminators as an alternative.

In extreme cases where a thorough and meticulous cleaning does not eliminate the problems of fish eyes, paint manufacturers have developed paint additives which overcome the problem and allow paint to flow uniformly and cover evenly.

Whichever fish eye eliminator product you intend on using on your paint project, be absolutely sure that you use only that product designed to be mixed with the paint system you are using.

The mixing instructions of all fish eye eliminator products are provided on container labels. Be sure to follow these guidelines carefully.

It would also be a very wise decision to use the fish eye eliminator for your chosen paint system throughout your entire paint job, along with the same mixture of paint. This will guarantee that the color tints and coverage uniformity is the same throughout.

How to maintain your level of protection.

In order to reduce the risk of developing future fish eye problems when touching up paint or when repainting, use multi-purpose vinyl dressings sparingly.

Instead of applying dressing to trim pieces directly, take a soft cloth first, apply the dressing onto that and then use the cloth to wipe the dressing onto the trim pieces.

Always make sure you thoroughly wash the entire car with quality cash wash soap in order to remove any trace of remaining silicone residue.

Flexible Additives

Newer cars frequently feature flexible urethane bumpers, spoilers, splash guards/mud guards and ground effects that are usually painted in the same color as the rest of the body.

Most of the time the paint materials used to cover these body pieces with are the same as those used to paint vehicle bodies with.

With these parts of the vehicle body work being flexible, a special additive is mixed in with the lacquer or enamel paint to allow its thin film to bend and yield with the body part without cracking, peeling or chipping.

This kind of paint additive is an absolute must if you want the painted finish on flexible parts to have any durability whatsoever.

The use of flex additives is not as common as it was in the past. With lacquers and enamels, flex additives were a necessity; however, they are not required with the more up-to-date urethane type products.

The vehicle parts that are to be sprayed calls for their surfaces to be cleaned and then scuffed using 800-grit wet and dry sandpaper. Scuffing promotes sound paint material adhesion.

As always, each paint manufacturer recommends its own brand of flexible additive to be used with its brand of paint products.

Be advised that when you are painting any type of flexible body section; consider using a flexible additive just to be on the safe side.

Hey! Just before you go...
  • Does you vehicle have damage to the bodywork?
  • Been given a sky-high quote to have this damage repaired and are now looking for alternative ways around your problem situation?
  • Perhaps you've struggled up to this point to find a suitable source of information on how to paint a car anywhere both on and offline?
If you would like to view professional video demonstrations of all of the basic auto painting stages involved in how to paint a car, please take a look at our highly praised solution: How to Paint a Car - The System.


That's all we have for you this week. Thank you very much for reading. We both hope this issue has been of valued interest to you.

COMING NEXT ISSUE: We complete our series on auto painting support products and take a look at what additional items are available for example, stir sticks, spray out cards and more. Until then...

Happy Painting!

Chris Curwen & Dave Gage