Converting from solvent-based to low-VOC paints may be safer and more environmentally friendly, but these benefits come with an array of new forms of maintenance. The responsibility of proper climate care is particularly important when working with water-based paints.

Because of the water in the paint, these coats carry substantial risk of complications in terms of poor temperature control. While such hazards are present when dealing with any kind of car paint, waterborne paints tend to be more susceptible to these problems and so need more attention. Preparing for these complications requires a combination of modifying your application technique and more importantly knowing what sets waterborne apart from traditional solventborne products.

Two key factors involved in working with waterborne paints are temperature and humidity. These can make or break the paint’s quality and usability before it is even applied. There a number of things that you can do to make sure that the cars you produce will have the shine and lustre that you are looking for, and there are a number of things you must do to save yourself the trouble of having to redo the finish.

Temperature

The good news: if you know the essential rules to temperature control, you don’t need to worry. What you need to focus on is awareness. Low temperatures are waterborne paint’s worst enemy. Water-based paints love to freeze in the cold, and some can’t return to the same consistency after thawing.

The optimal temperature in which you should store your waterborne paints should be between 15 to 35 degrees Celsius. Let it fall lower than five degrees or rise higher than 40 and you risk damaging your supply. If your paint has experienced a shift in its colour or if it has started to gel, then you are going to need to re-evaluate how you’re storing it. The ability to salvage your paint once it has turned varies by paint brand, so make sure to contact your supplier to see how much you can save. Most suppliers will cover this topic and much more related to the handling and storage of waterborne basecoats during their technical training sessions.

Humidity

It should be of little surprise that when you are working with water-based paints, the level of water in the air plays a role in how quickly it dries. Waterborne basecoats can have a higher flash time than solvent based paints.

Dale Beatty, assistant manager of Paint Two paints, believes that the optimal humidity of your paint booth during application should be at 72 per cent with only a +/- three per cent variance. Too little humidity and the paint dries too quickly causing you to lose some of your sheen. Too high and some moisture gets caught beneath the clear coating during curing which eventually causes boils to show up, otherwise known as “popping.”

There are different kinds of equipment and techniques available to prevent excess or insufficient moisture from causing a problem. The conventional option is simply using hot air drying techniques. Although it is tried and true in the past, it is not the best method for waterborne since it carries the risk of popping. However, having a constant stream of air blowing parallel to the surface will help move away layers of humid air that will inevitably hover above the coating during drying.

One alternative you may want to consider is using a wet booth. They are often utilized by modern car manufactures and they help reduce excess water and paint particles in the air by drawing it into a grating below the surface and into a water trough. Of course, this will involve another level of waste management, so that is something you should consider before making the switch.

Things to Remember

Maintaining water-based paints is not more complicated than maintaining solvent-based paints. Almost everything you already know about storing and applying coatings applies to waterborne. The differences you will encounter are essential to know, but are also minor compared to everything else you’ve already run into. You should always make sure to contact your paint supplier on the best methods to maintain their particular brand because some of the specifics do vary between companies.