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26 POWDER COATING, April 2016 Training your customers to become better finishers — Why putting it on "extra thick" is not an option and other requests to avoid It is inevitable that at some point in your cus- tom finishing career, you will encounter a request to fix an error that is out- side of your control. In this article, I will share a summary of some key design, fabrication, and processing considera- tions that should be avoided–and why. At best you may be able to help every- one save some money and improve quality, and at the very least you will be able to avoid an ugly situation that will cost more time and money than it is worth. Coating alone will not fix defects As an aesthetic and functional last step in the design and fabrication process, powder coating makes our customers' products look good – really, really good. However, the coating that we apply is less than one quarter of the thickness of your fingernail. Suffice it to say, while it is an amazing product, powder coating cannot fix everything that has happened before its application. Grinding marks, weld spatter, missed welds, pitted steel, rough mill scale, pin- holes, tool marks, bad welds, warping, blown out welds (after curing), perma- nent ink, and machining fluid are a quick list of common defects that you may unexpectedly encounter once a project hits your shop floor. In almost all instances, these defects can be avoid- ed if the customer knows to give them some consideration ahead of time. A word of warning You do not want to own your cus- tomers' issues. While it is admirable to want to provide complete customer sat- isfaction, it is dangerous to take respon- sibility for issues that happen before the job gets to your shop. Just because you have a welder in your shop does not mean that you are responsible for repairing a structural weld on your cus- tomer's suspension bridge components. Imagine the consequences… Furthermore, there are limits to what we can accomplish as powder coaters. Stick with what you are good at: Surface prep, finishing, and shipping a product that looks as good when it arrives as when it came out of your oven. Training customers Stopping a problem before it starts is the best way to avoid delays and costly rework. The fol- lowing is a list of com- mon and not-so-com- mon issues that you should be aware of when evaluating the first job from that new customer. Sharp edges: Any coating will naturally recede from a sharp edge. Furthermore, impact on a sharp edge is more likely to cause the coating to disband than on an edge that has a radius. Photo 1 shows a coating at its thinnest point. This coat- ing will fail if an inadequate coating sys- tem and/or surface preparation is applied. Sandwiched metal: Overlapping joints that are not seam welded will allow moisture and contaminants to pene- trate over time. No coating, liquid or powder, will penetrate these tight gaps. In time, corrosion will start at these mating points and failure will occur. A few suppliers have a caulking product that can be applied before coating, as shown in Photo 2. While I have no hard technical data, we have been using one . Coater's Corner Coater's Corner Chris McKinnon Aegis Industrial Finishing Photo 1 Photo 2 Photo 3 Photo 4