Volatile organic compounds (VOC) in paint have been recognized as bad for the environment; consequently, there is a movement to reduce VOCs and this will affect practically everyone who paints – waterborne.
The move to less toxic, water-based finishes is already well under way. Waterborne paints are currently in extensive use in Europe and Canada, and many OEMs now use water-based paints. A number of states around the country have enacted regulations that are gradually forcing shops to lower VOC emissions.
The consensus is that the transition to water borne finish products may not be as difficult or as costly as some first supposed. Below are answers to several of the most asked questions regarding the conversion to waterborne.
Am I faced with a large equipment investment by switching to water?
Not necessarily. You can switch to waterborne with no equipment changes and still get good performance. However, to truly enjoy the production benefits that water can provide, we recommend investigating air movement equipment, especially in humid climates. You should also consider a waterborne spray gun, a new waterborne gun washer, and perhaps an air filtration system if your current one is not performing well.
Will I need a “special” spray gun?
Spray gun manufacturers have been working diligently to offer painters a gun that not only atomizes waterborne paint properly, but also has internal parts that will not degrade or rust. The spray gun you use now may work as is, or you may have to buy the appropriate needle/nozzle/air cap setup, or you may want to buy a new gun.
We strongly suggest using separate spray guns for waterborne coatings in order to avoid contamination and material clotting. If water and solvent borne base coats are used in the same spray equipment this could cause equipment damage, contamination, and costly redoes.
In addition to the waterborne spray guns, we recommend the use of a disposable cup system. Disposable cups make paint clean up easy and cost effective. It also expedites color change, reduces time and material clean up and is safe from outside contamination.
What about my air supply? Will I need to make changes?
The use of waterborne basecoats definitely requires new air treatment tools. When spraying waterborne paint it is required that the air is free of oil vapor and dirt. Even the slightest amount of contamination can cause coating imperfections. It is highly suggested that your shop is properly piped and has an adequate air filtration system. Check compressor ratings to ensure it can meet the air supply demands of the equipment used in a shop – including dryers, filters, and spray guns.
How will the regional climate impact waterborne? What if I work in an area with large temperature changes and/or high humidity?
When working with water-based products it is extremely important to pay attention to proper climate control, especially in locations that have cold winters or exceptionally hot summers.
Two key components involved in working with waterborne paints are temperature and humidity. Neither of these factors should be taken lightly. Low temperatures can cause your product to freeze. The optimal temperature that you should store your waterborne paints should be above 35° F. If the temperature falls lower you could risk damaging your entire supply. If your paint has experienced a shift in its color or if it has started to gel, then you are going to need to re-evaluate how you’re storing it.
Humidity plays a huge part in how quickly paint dries. If there is too little humidity, then the paint will dry too quickly causing you to lose some of your luster. Too high and some moisture will get caught beneath the clear coating, which will eventually cause “popping” and “blushing.”
Will I need to change my prepping and paint mixing areas?
The answer to this question is simply, “How sound are your existing principals?” If you were very focused on maintaining a clean operating environment, then any changes will be minimal. If instead, you were a bit lax, then the adoption of waterborne paints will require changes.
Simply tips include (i) washing the vehicle thoroughly before work begins, (ii) keeping the floors and surrounding areas clean and dust-free, (iii) changing paint booth filters regularly, (iv) disposing of all used rags and other waste immediately, (v) not storing jackets, shirts, or other sources of fibers in the mix room, (vi) keeping paint canisters sealed and stored properly, and (vii) ensuring that the airflow system is working at all times. Best practices call for developing a daily cleaning.
Will I need to use waterborne undercoats and clearcoats?
No. Waterborne basecoat performs best when used with solvent-borne urethane undercoats and clears.
Are all waterborne basecoat products are the same?
All waterborne systems vary from each paint manufacturing company. A huge factor is the shelf life and the stability of the product. Blendability and tape times can differ as can the ability of temperature to affect the product. All waterborne systems are made up of acrylic and polyester resins, with each paint manufacturer using different proportions and different combinations of the two.