Quantcast
Channel: Power & PerformanceTech Stories – Power & Performance
Viewing all articles
Browse latest Browse all 117

Water Color

$
0
0
With the waterborne paint, we only add 20 percent thinner as opposed to solvent-based paints that generally use 50 percent reducer. These reducers are specifically designed for use with waterborne systems, so make sure you have the right product before you start.

How to apply waterborne paint products

Words: Cam Benty; Photos: Cam Benty and Iwata

Our ’66 Chevy pickup had come back from the dead, smoothed and shaped to original configuration and was now ready for a fresh paint. We knew we wanted to stay with the same color, but the remaining question was whether to use waterborne or solvent-based paint.

Waterborne paints have been around for a decade or so, but today are all the buzz. For those who have come to know waterborne from personal experience, they have learned what it takes to achieve success. For those who have not sprayed with water, it is an unknown that makes them uneasy about the results they will encounter. As with anything, it’s simply a matter of having the right tools for the job and knowing what to do.

Currently, waterborne paint is limited to the pigment layer of the painting process; the primer and clear coats still retain the solvent-based chemical and are used with equipment we all know and love. Applying waterborne paints requires a host of ancillary tools and techniques to achieve a smooth, run-free final appearance. A changeover is not simple, but clearly (and luckily) from those painters we’ve polled, waterborne paints perform well with excellent final results.

As with anytime new paints or equipment are used, we suggest practicing on some random, non-important surface until you achieve some competency. Waterborne paint is different from solvent-based paint — different mixing techniques and spray guns, and those mysterious dryers required for proper laying out of the paint.

When working with waterborne paint, make certain you are protected from toxic fumes and materials. It is critical to frequently change out air respirator canisters in your breathing apparatus and dust off that full-body, paint protective suit.

Follow along as we show you the basics and beyond of waterborne paint application.

Step one was to locate the right color for our project. This paint chip matched the color paint we desired. This match is pretty good. Waterborne paints can be mixed to match just about any color you desire, old or new. By using the computer mixing system, we were able to discern the exact color required to match the hue we wanted. Our professional mixing pro selected the right combination and helped mix up a batch of waterborne paint for our project. First, we poured in the base toner. These toners are stirred and not shaken like most solvent-based paints. Note how easy it is to generate bubbles when simply pouring the base toner in the mixing container. These bubbles need to be removed through straining/filtering before they enter the spray gun.

The colorizing pigments are added to the base toner. Here, we introduce the green pigment that dresses our truck. The paint is mixed, weighing the different pigments to achieve the target color. The order in which the paints are mixed is not critical to final coloration. While we know the final coloration will be wonderful, there are a number of other pigments required to achieve the correct color combination. This computer system weighs the ingredients as they are introduced into the base coat, to make certain the right final color is achieved. This is a precision procedure that requires critical measurements. The paint pigment container openings allow you to control the exact amount introduced. Note the attention to detail required to make sure each batch is exactly the same. The paint is stirred — as noted earlier — not shaken, but must be completely mixed to ensure proper color consistency. It’s not a bad idea to look at the final mixed color and compare it to the final target color. Do not be alarmed if the color is not the same in the liquid state as it will be in the final dry placement. Waterborne paints often look darker in the liquid form. Prepping the panels for waterborne paint is slightly different than the process used for solvent-based paints. Sand the primered surface with 600-grit paper and then with waterborne paint-specific contamination cleaner. Standard methods involving tack rags are not advised. As is the case with paint color mixing, the base coat should be thoroughly stirred with care, avoiding creation of bubbles and ensuring consistency throughout. Straining the paint prior to filling the spray gun is key — and not just to get clumps of paint or dirt out of the paint mix. The paint should be free from bubbles, which can be removed with a straining funnel. Coverage is excellent with the LPH 80 Iwata spray gun. These dryers are used to remove the water in the paint — and are required for waterborne paint.  For our painting effort, three layers of base coat were required to set up a proper foundation of color. Dry time was only about 5 to 15 minutes between coats. The paint must dry evenly, so we put the dryers to work. These are specifically designed for waterborne paints. For the first color application, we did not tape off the area that was to be painted white so we avoided the common build-up problems that occur with many paint projects.

With the center of the panel painted, we covered the area with tape to make it ready for application of the surrounding color addition. The exterior color coat goes on next. The paint should be applied smoothly and evenly, not attempting to cover in one coat. Gun movement speed is pretty fast, and the gun spray should be about three to four inches from the panel when applied. A standard spray booth like those used for solvent paints can be used for waterborne paints. This dust-free environment is helpful (but not imperative) to waterborne paint projects. Note that you must have a waterborne compatible gun for this process or the internals on the gun could corrode over time. Slowly remove the tape when the paint is dry, pulling back against the direction of the tape to make sure it cuts a crisp edge where it breaks from the original painted section. Never sand the base coat before applying the topcoat, as it will adversely affect the porosity of the base coat and introduce scratches to the surface. If you sand the base coat, you will see the sand scratches in the final work through the topcoat clear. The final effect of waterborne paint is high impact. You can increase the final look in the normal solvent-based paint style by color sanding and buffing the final surface. However, unlike many solvent-based paints, waterborne does not require these steps to achieve a great shine.

Source: Iwata spray guns, iwata-medea.com


Viewing all articles
Browse latest Browse all 117

Trending Articles