In these economically difficult times, we all are looking for ways to cut cost, keep a step above the competition and gain more of the market share. One place we often cut cost is through our lacquer thinners. When we choose to purchase “cheaper” thinners thinking we are saving money, many times it is costing more in unforeseen problems and rework that lurk around the corner.
One of the No. 1 reasons for finish failure is solvents; most specifically “lacquer thinners.” Zero out of five chemists approve of adding generic thinners to their coatings.
By definition, lacquer thinners are a blend of solvents. Solvents can be active, latent or diluents, and they all have specific evaporation rates and react to coatings differently. This is why when the wrong lacquer thinner is used we develop problems in drying, orange peel, pin holing, printing, recoat windows, solvent pop and more. Have I made my point yet? It is always wise to use the manufacturer's recommended solvents in their finishes and to use them in your final clean up as well.
Let me next help you better understand why it’s just as important to use the same thinner in your final clean up. Imagine you have a glass of sugar that you need to dissolve. If you pour cold water into the glass, the water will dissolve the sugar only after you agitate it for a while but you will still have tiny bits of crystal afloat in the glass. If instead you use hot water in the glass, the sugar will dissolve instantly! This is the difference when using the wrong thinner vs. the right thinner. You can achieve the desired results knowing what solvent to use and when.
I receive several calls during cooler temperatures when shops are experiencing finish wrinkling, drying time taking forever or worse yet will not cure at all. When asked “what, if any, solvents were added?” their answer is “just the same stuff I have been using all summer and never had a problem with.” Herein lies the problem. During the summer months they may have been adding retarders or flow enhancers to the coating to help slow down the film from forming too quickly to avoid blushing or other problems due to extreme temperatures from heat/humidity. In cooler temperatures the finish is already slow to cure and by adding flow enhancers or retarders the additional solvent blend could keep the coating open too long to cure properly thus the problems starts resulting in recoat windows or printing issues, etc. Knowing the types of solvents that are compatible with your coatings and how they react before adding to any finish is paramount to your success while remembering that climate conditions play a large factor.
Coatings have several blends of solvents in them. To start with, these blends of solvents determine how the coating will lie down, flow, dry, form the film, etc. This is exactly why we need to be mindful when starting to change up that blend by adding “lacquer thinners.” Most manufacturers try to have their coatings formulated as “ready to spray” in viscosity. If you wish to change the viscosity it is always best to first try to change the temperature of the coating before adding solvents. By changing the temperature, you will not lose solid content and will build that coating much faster, resulting in fewer coats needed to spray, saving money on both materials and labor.
To understand this better, let’s use the following analogy: Think of having a stack of pancakes that you want to cover with syrup. If you take syrup from the refrigerator and pour it over your pancakes it has a hard time flowing and penetrating into the pancake. If we add water to the syrup, we are thinning the syrup to flow better but what did we really do? It did not really flow any better and now it just tastes bad as well. However, if we were to heat that same syrup, it would flow, level and penetrate much nicer and most importantly maintain the integrity of the syrup.
Remember to always contact your supplier or manufacturer of your coatings to find out what lacquer thinners they suggest to use in their coatings and remember, “always thinning no matter what, will not save you time or money,” it could instead be costing you.
Ed. note: Diane Shattuck comes from a family of craftsmen in the woodworking industry. Through the guidance of her father, she started finishing at the age 16. It was working under the instruction of artisan, Chris Peters from Holland that ignited Diane’s passion for teaching. Her love of coatings keeps her engulfed in seminars and trainings to stay abreast with the latest techniques and technology. She currently works for ML Campbell’s largest distributor, Wurth Wood Group, as a coatings specialist. Her assistance has come in many forms including finding ways of increasing profits with or without minimal spending through audits and programs designed specifically for their facility. Diane’s wit, humor and hands on approach add to her unique teaching style.