![]() The key point in the video is that if you maintain consistent application conditions, the need to add solvent and make process adjustments can be minimized – often eliminated.Īs you’re working with your paint supplier to create the perfect formulation, ensuring the right color, gloss and adhesion properties, it would be ideal if you could maintain predictable properties all the way through your application process. You can find that video by clicking here. We produced a one-minute video on altering paint which does a nice job highlighting this issue. (Given our knowledge of viscosity change as a function of temperature, we would add temperature to that list.) At a minimum, you are setting up the next operator with a more complete understanding before he or she begins making adjustments or additions. If you do need to make a solvent addition, he recommended that you record when you made the addition, how much you added, and why you added it. ![]() This is where you can generate issues that ultimately create the appearance of paint batch variation. flow rate, atomization, gun speed, etc.). ![]() However, he observed that paint can be altered to suit an operator’s preference and is often done in conjunction with other process adjustments, (i.e. For example, after a long break period, it may be necessary to replenish the solvent that has been lost due to evaporation. There are times where an operator needs to add solvent. (For purposes of this summary, we will use solvent to refer to both solvent in solvent-based paints and water in water-borne paints). ![]() His fourth and perhaps most significant observation concerned solvent additions combined with arbitrary process adjustments. This is an important distinction as oxidation is one of the primary forms of degradation for most chemicals. Another important difference is that agitation can entrap air in the paint – and how much depends on the degree of agitation and how long it continues – whereas tumbling limits air exposure to that already in the drum. While tumbling and agitation serve much the same purpose, tumbling mixes the paint before it is used, whereas agitation mixes the paint as it is being used. He admitted that most end users do an adequate job of agitation. His third observation was that the paint needs to be agitated. A simple tumbling before using the paint helps blend everything and put the pigment back in suspension to promote consistent color application. The resin, pigments, and solvents can, and do, separate as the paint sits stagnant. His second observation was that the paint is often not tumbled before it is used. Those companies that adhere to FIFO are less likely to suffer from changes that take place as those paints age. Add to this list that small volume of air in the top of each drum. The amount of change varies by formulation and is the result of the reactions between the myriad chemicals that make up a specific paint. His first observation was that end users sometimes ignore FIFO, (First in First out). We thought his insights were helpful, so we decided to share a summary of them here. He said what we often hear from paint suppliers, “Our paints don’t vary much from batch to batch.” When we asked why their customers often have a different perception he said, “Most of the variations that they see are self-inflicted.” That prompted us to request a more in-depth conversation so we could better understand how end users may be unknowingly creating their own batch variations. During our conversation we discussed the batch-to-batch variation of the paints they supply. At an event recently, we struck up a conversation with an Account Manager at one of the major paint suppliers.
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