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TBM AT JETCRAFTERS AVIATION. JET AVIATION PAINT FACILITY. specific to their systems and processes. It’s no wonder too; the process is mind- blowing, from start to finish. Step 1: Paint Stripping and Inspecting. The estimated time to complete this first step is about a week. To begin, a shop will start by preparing the metal surface to be painted. Some would say this prep work is likely the most criti- cal step in the whole process to ensure the longest-lasting paint job – and an additional check that allows you to catch skin corrosion issues early before they become bigger problems. This is also where, as they say, “you get what you pay for.” Some shops will start with a scuff process, where they don’t actually strip the old paint off, but rather scuff or sand the old paint so the new paint will adhere to it better. There are a couple of issues with this technique: 1) The process doesn’t allow you to catch any skin or fastener corrosion as easily; 2) The process usually ends up mak- ing the aircraft heavier than if it were completely stripped and then painted. The best form of metal preparation for a paint job includes removing of the control surfaces to better gain access to all areas of the airplane and then using a chemical stripping process (using Peroxide or similar chemical). This is where the EPA comes in. Safe han- dling of the wastewater associated with this process requires the shop to cap- ture, contain and properly dispose of these chemicals. This alone can cost several thousands of dollars per air- craft. But this sure beats having to deal with a skin repair later. That’s because a good shop will end this stripping process with a thorough inspection of the entire aircraft. This is an important step because this is when issues can be found early and how a more expensive repair is avoided down the road. Pro Tip: Whichever shop you choose to have your paint done, make sure they are equipped and approved to handle repairs for your airframe. That way, if corrosion or other issues are found that require maintenance, you can have it ad- dressed on site and with minimal delay. Step 2: Surface Prep and Base Color Application. Next is preparing the surface for the base color application, which also takes about a week. Again, this step can likely be a difference of years in the life of your paint job, so don’t skimp here either. This is where the PhDs of aircraft painting come in. It used to be the process of painting cars and painting aircraft were very similar. Today, however, the process is very specialized, especially considering all the concave and convex surfaces, extreme temperature and speed varia- tions, and the fact there are vertical, horizontal, topside and underside sur- faces to consider. Some of the best paint shops use a prepping process that includes both Alodine (to form a protective barrier on the metal) along with a two-part epoxy primer. It’s not as easy as it sounds. Alodine is another extremely effec- tive, yet nasty chemical that requires special handling and disposal, equating to more dollars in cost. After this, the epoxy primer must be applied precisely in a climate-controlled, dust-controlled and well-ventilated paint shop. This is where the rubber meets the road – or paint meets the metal – and where you’ll be blown away by the painting process. And guess what? More dollars adding to the overall cost! Paint booths are amazingly sophis- ticated these days. Some of the most advanced shops are using a high-tech electrostatic process that allows for the charging of the paint molecules providing a 60 to 75 percent efficiency (meaning 60 to 75 percent of the paint makes its way onto the surface of the aircraft) and minimizes paint waste. The sophistication doesn’t end there. The paint booths are also equipped with special lighting and multi-stage filtration systems in the f loor, ceil- ing and walls. That’s after they spray water on the floor and walls up to four feet high prior to painting just to keep dust and other particles from f lying around. Again, only stuff the “Paint PhDs” would know. Step 3: Base Paint Rework, Application of Stripes or Other Detail Painting, and Painting of Control Surfaces. The timing of this step varies largely based on the size of the air- craft and the complexity of paint de- sign, but expect one to two weeks on average. “Roughly 10 percent of each paint application will not pass our standards,” says George Euler, paint shop manager at West Star Aviation’s Grand Junction facility. It is a testament to the high stan- dards they have for aircraft paint. Imperfections such as dust particles, “fish-eye” spots (small bubbles in paint), or “orange peel” (uneven or rippled surface caused by humidity) are areas Jet Journal May 2020 / TWIN & TURBINE • 21