Lessons in painting proccesses for aircraft
By Michelle Garetson
Aircraft paint schemes are not just about looking good on the runway or in the hangar. The type of pain tthe "canvas" (airframe), and especially the application and the upkeep all need to be considered before deciding on Maui Blue or Rainforest Green.
Paint is more than aesthetics — it affects the weight of the aircraft and its aerodynamics. Paint helps to protect the integrity of the airframe. It can also impact the economics of operation as the more downtime incurred from frequent painting and paint maintenance, the less time the aircraft is available for revenue-generating assignments. However, the aesthetic aspect can affect how "safe" one feels about an aircraft. Seeing chipped and cracked paint around a doorway as one boards the aircraft will give one pause as to how well the rest of the aircraft is maintained.
Once while boarding a small, commuter plane, a passenger looked out the window and exclaimed to the rest of the group that there was a crack on the engine and that he was not going to fly on this plane. Granted, the pilot came for a looksee, and in an effort to appease the passenger, sent for the maintenance crew to check it out.
Our passenger-induced maintenance resulted in a flurry of panic for many onboard who quickly consulted their airline timetables for another flight. As it turned out, the "crack" in the engine was a split in the paint on the nacelle. The inspection and subsequent diagnosis took very little time, but it took almost an hour to get some of the passengers calmed down and back on the plane.
Painting is an art
Aircraft painting is an art and a skill. Given the myriad of materials being developed for airframes, the aerospace coatings industry must keep pace with every advancement and those who perform paint application must also stay current with new products, new technologies and new application techniques.
In November 2000, The Sherwin-Williams Company opened a 25,000-sq.-ft., state-of-the-art facility in Andover, Kansas, near Wichita, for its Aerospace Coatings division. The new building incorporates training classrooms, customer service offices, color blending labs, and research and development offices.
A 20-ft by 45-ft., temperature-controlled paint booth is the highlight of the facility as it will be used to train application technicians of all skill levels in improving their craft.
No matter what type of environment these technicians work in — whether it’s Miami in July, Minneapolis in December, or something in between — the paint booth can be programmed to achieve those conditions so that technicians can best learn how to perform painting and depainting processes within those constraints.
Stuart Mack, Director – Technical Development for Sherwin-Williams Aerospace Coatings is responsible for the development of the various training programs on offer at the facility. The curriculum covers a wide spectrum of painting and depainting issues, as well as safety and environmental matters.
The inaugural training modules began in February 2001. Mack says the people who should attend the training courses vary from application technicians – of all levels of expertise – to supervisors and managers, to salespeople and distributors. Each of these groups will benefit from obtaining a better understanding of the tasks involved and best practices for painting aircraft.
"Class size is limited to 12 people right now," explains Mack. "We will continue to revise and develop the curriculum with feedback from attendees."
Some of the training modules available involve Depainting and Preparation for Painting; Topcoating; Touch Up and Spot Repair; Interior Coatings; Equipment and Spray Environment; and Safety and Environmental Issues. At the end of the training, attendees are awarded a Certificate of Completion and shops are presented with plaques from Sherwin-Williams.
High solids vs. low solids
"It is very different to paint using a compliant, high solid coating than a low solid coating," cautions Mack. "High solid coatings have a lot less solvent than low solids — it’s the solvent that is the carrier of the pigments, resins, and additives that make up the paint."
While the EPA warns of the dangers of excessive solvents, for the technicians, less solvent in the mix produces new challenges in the application.
"Equipment and its setup become very important when making the shift from conventional painting processes to high solids application," continues Mack. "Sherwin-Williams tries to help the end user properly configure equipment in order to promote a successful shoot."
The same holds true for objects to paint. The training center provides a variety of airframe materials for students to learn and practice the painting processes, or students can bring in their own materials.
Wax on, wax off
With so much riding on the success or failure of the paint job, upkeep is an integral element to the well-being of the finish.
"Some waxes can actually hurt the paint it is supposed to protect," says Mack.
And, according to Mack, you can’t use just any cleaner on aircraft. Scrubbing splattered bugs off the wing with abrasive pads will do more damage than the bugs ever did.
"Cleaners, and even waxes, can contain cleaning agents that can do harm to the thin layer of protective resin on the surface of the aircraft."
For this reason, Sherwin-Williams has developed its own polish and cleaners to work specifically with – not against – its paint products.
Customer feedback is important and encouraged at the training center. Not only will comments on the courses be helpful in improving the overall training experience, but Sherwin-Williams asks for feedback on the products in an effort to help its Research and Development team improve present and future offerings.
Dallas Finch, the Facility and Technical Director at the Aerospace Service and Training Center, offers that it’s no accident that the training center, color labs, customer service, and research and development are all under one roof.
"Excellent testing equipment certainly helps in the development and improvement of new products and improvement in our existing products," says Finch, "but ultimately, the customer input as to how the products perform in real-life, real-time situations provides the greatest influence in the work being done by our research team."
How long should a paint job last?
Mack explains that the life expectancy of a paint job is directly related to its care and maintenance. Granted, there are some aircraft owners who wish to have their planes painted every year, whether it needs it or not, but a well-maintained aircraft that is properly stored can last for many years.
The new training available at the Center provides attendees with the latest information on proper coatings application techniques and coatings-related matters to help them better serve their customer’s aesthetic, safety, and economic needs. AMT
Paint and Paint Supplies Listing
14296 W 130th Ave., Cedar Lake, IN 46303, (800) 864-7382, www.sprayboothfilters.com
Spraybooth Filters from AJ Dralle, Air Flow Technology, Tri-Dim and Paint Pockets. Roll-Trad Curtain enclosures of all sizes and types.
525 Locust Grove, Spartanburg, SC, 29303, (800) 289-5762, www.contecinc.com
Contec® is an ISO 9001 registered manufacturer of surface preparation wiping materials including PROSAT® Custom™ and SATWipes® presaturated wipers. TaxFre® and Taxnit™ tack cloths, and other specialty wipers, up to Class 10 cleanroom processed. Utilizing its expertise in critical environments, Contec has developed products specifically designed for the Surface Preparation Industry.
DeVilbiss Industrial Coating Equipment
1724 Indian Wood Circle, Ste. F, Maumee, OH 43537, (419) 891-8200
Releases a new piece of literature to help educate the reader on improving finish quality. "Don’t Starve Your Spray Gun For Air" is available from DeVilbiss by mail or toll-free on (800) 338-4448.
DINOL (U.S) Inc.
14826 NE 95th St., Redmond, WA 98052, (425) 556-5114
Supplies corrosion inhibiting compounds, coatings, and cleaners to the aerospace industry. As a full system supplier, we also supply airless and airmix application equipment along with special nozzles for the application of different coatings — from solvent to water base.
4475 River Green Pkwy., Duluth, GA 30096, (770) 613-0777, www.formulatech.com
Manufacturers of a full line of premium cleaners and degreasers including Fleetworks, a water-based aircraft and automobile body wash. Fleetworks makes it possible to perform a more thorough inspection when checking for potential maintenance problems.
Gage Products Co.
821 Wanda Ave., Ferndale, MI 48220, (256) 233-3929
Provides paint-related specialty chemicals and services including solvents, transfer efficiency additives, washable and peelable temporary protective coatings, booth coatings and cleaners, cure oven cleaners, and presaturated wipes.
PRC-DeSoto International Inc.
5430 San Fernando Rd., Glendale, CA 91209, (818) 240-2060, www.prc-desoto.com
Supplier of DeSoto® and Celomer® aerospace coatings, PRC® and Pro-Seal™ aerospace sealants, and Semco® application systems — brands that have been recognized for quality, consistency, and ease of use for over five decades.
Pauli Systems Inc.
1820 Walters Ct., Fairfield, CA 94533, (707) 429-2434, www.paulisystems.com
Strip paint from composite and metal surfaces WITHOUT chemicals. Pauli Systems offers equipment from blast cabinets to blast rooms to full hangar facilities.
RPC Specialty Coatings
1510 Hal Henard Rd., Greeneville, TN 37743, (423) 787-0057
Premier powder coating in a state-of-the-art facility. On-site lab for testing with salt spray capability.
Randolph Products Co.
701 12th St., PO 830, Carlstadt, NJ 07072, (201) 438-3700
Randolph Products is a major source for specialized aircraft and MIL-SPEC coatings to the entire aircraft/aerospace industry. FAA-PMA Coating systems on Ceconite-OEM proven MIL-SPEC QPL-variety of products including specialty items. Large distributor network.
The Sherwin-Williams Company – Aerospace Coatings
415 E. Commerce St., Andover, KS 67002, (888) 888-5593 or (316) 733-7576, www.sherwin-williams.com/aerospace
The Sherwin-Williams Company offers the proven, superior exterior coatings, Jet Glo™ and Acry Glo™, as well as Jet Flex™, a new outstanding interior finish. Jet Flex is available in a solvent-based coating that meets BMS 10-83 and also as a water-reducible coating.
PO Box 66760, St. Louis, MO 63166, (314) 674-5907
Makers of SKYKLEEN aviation solvent, a non-caustic, non-combustible, biodegradable solvent with low VOC and low odor that replaces MEK.
131 1/2 Lynnfield St., Peabody, MA 01960, (978) 531-2279;
Manufactures aircraft paint strippers that fully conform to Boeing D6-17487, TT-R-2918 and is approved by the US Department of the Air Force. Available for spray applications, brush on or a version designed for parts immersion.
U.S. Paint Corp.
831 S. 21st St., St. Louis, MO 63166, (314) 621-0525
Manufacturer of high gloss, high durability exterior and interior coatings products for a wide variety of aviation applications. Makers of AWLGRIP (formerly named ALUMIGRIP), the first urethane system to gain acceptance for commercial, business, and military aircraft.
Uni-Tech Consulting Inc.
7553 W. 99th St., Bridgeview, IL 60455, (708) 361-3385
The sorbent "amps" aircraft mobile paint station roll around portable paint booth, which recirculates air and absorbs VOCs and overspray with five stages of filtration including activated carbon. Operates on 120-volt line current.
400 Jarvis Dr., Morgan Hill, CA 95037, (800) 648-2661
Zip-Chem introduces the Clip-Pak® and Multi-use Spray-Pak for touch up paint and primer application. The kit allows user to mix, spray or brush from a pre-ratioed, self-contained no-waste package. Zip-Chem also offers Alodine® Chemical Conversion Coatings 600 RTU, 1000RTU and 1200 RTU Brush in Henkel factory backed ready for use down-sized packaging.