Two issues ago, we featured an article from Sureflight LLC, in Coatesville, PA, on painting your helicopter. We also featured an article from Julie Voisin, Global Product Manager, Aerospace Coatings, Sherwin-Williams Company, on choosing the right paint for your helicopter. If you work in your company’s paint booth, or are responsible for the finish on your company’s aircraft, you know that paint is not all you will find on the exterior of many aircraft. In many instances, there will also be vinyl graphics for designs, registration numbers and even logos.
What are Vinyl Graphics?
Vinyl graphics have been around for many years as a functional way to decorate cars, trucks, windows and aircraft. When contemplating whether to place a vinyl graphic on a helicopter’s surface, there are many useful points to know about beforehand.
Vinyl graphics are designs or patterns made of vinyl material with an adhesive backing, making them resemble semi-permanent window clings. They are used for decoration and making a surface more pleasing to the eye. Vinyl graphics can be used on almost any smooth surface, making them an ideal choice for decoration material. They are usually applied by peeling the graphic to be installed from the backing material and applying it to the helicopter’s surface, much like a sticker.
Vinyl graphics are not stickers or temporary tattoos. They generally have to be bought from a store that specializes in vinyl graphics. Since they are available for just about any type of transportation vehicle, it is important to contact a shop that specializes or carries vinyl graphics for aircraft. Because they are made of vinyl, they have to be made and cut out using a special tool.
Vinyl graphics are backed with a strong adhesive, and the vinyl material makes them effectively weatherproof and durable. This is unlike stickers, which can bubble, peel and wash off. The adhesive on the vinyl makes them good for decoration on just about any smooth and even exterior surface such as metal or fiberglass. Most places that sell vinyl graphics can make a custom design based on what you like and where the graphic will be placed.
Due to the versatility of vinyl graphics, designs and decals made of vinyl can be made in almost any size needed. Turning the design of a huge building or sculpture into a decorative, original 12-inch graphic is possible. Taking a small insect such as a butterfly and ballooning it into a three-foot graphic for the fuselage of your helicopter is also possible. Vinyl graphics can literally be made into any size a customer wants.
Have you ever seen those massive logos on the tails of airplanes or the lettering along the side, or how about the other decor on smaller jets or helicopters? Yes, sometimes it’s painted on, but sometimes it’s vinyl.
For the following information on vinyl graphics, I had the opportunity to talk with the folks at Adnormous Graphics in Smyrna, GA. They make vinyl graphics for just about any kind of wheeled vehicles and aircraft!
“Applying vinyl to aircraft is a special niche market. If you can respond to that and learn how to work with it, you could gain some business,” says Greg Duchinsky, the marketing director at Sharpline Converting, a vinyl graphics manufacturer based in Minneapolis, MN.” You can make lettering for the fuselage, do trim accents, pinstripes down the side and even work your way up to jumbo jets.”
Preparing the surface
As with any substrate, all aircraft surfaces are considered contaminated until they have been properly cleaned. That means you’ve got to clean the helicopter before you can apply the graphics. You might need to get on a lift to reach it, but other than that, cleaning a helicopter isn’t a mystery.
Basically, it’s a three-step process, according to Sharpline’s “technical gurus.”
1. Saturate a clean paper towel with a solvent approved by local EPA regulations (VM&P naphtha) and wipe the surface to remove any contaminates such as silicone, chalk or adhesives.
2. Dry the surface with a lint-free paper towel before the solvent evaporates.
3. Spray the surface with isopropyl alcohol and dry the surface immediately with a clean, dry, lint-free towel. This should remove any residue remaining from the cleaning solvent.
Some Things to Consider When Applying Vinyl Graphics
The adhesive is sensitive to temperature; if it is too cold, the adhesive will not be soft enough to properly bond with the surface, and extra care will be needed when removing the spacing tape. Once the temperature increases, the adhesive will properly cling to the surface without any adverse affects. When working with aircraft, it’s best to apply vinyl graphic products when the air and application temperatures are above 50 degrees and below 100 degrees. That doesn’t automatically rule out cold weather installations — you just need to get a little more creative with your tools.
Surfaces may be artificially heated when air and application surface temperatures are below the minimum requirements. You can use a portable heater, heat lamps, hot water or steam. If hot water or steam is used, however, the surface must be dried thoroughly before application of the graphic.
Don’t Install the Graphics in Direct Sunlight
Even on a cold day, direct sunlight will make the adhesive much more aggressive. It is best to apply the graphics in a shaded area. If you are applying the graphic using a wet method, make sure your solution does not evaporate before you are finished. If necessary, rewet the mounting surface and graphic as required.
Large Graphics Can Be Difficult for One Person to Handle
Having someone help you hold the graphic can be a life saver. This allows you to focus your attention on pressing the graphic to the mounting surface without bubbles. Also, if your graphic has separations (like spaces between letters), you may cut your graphic apart for smaller, more manageable pieces. This should only be done after the graphic is temporarily in place with masking tape to maintain the proper spacing.
Don’t Stress Over a Few Bubbles
Smaller bubbles will disappear through time due to barometric changes. If the bubbles don’t go away by themselves, you can always pop them later with a pin to let the air escape. To accomplish this, simply puncture the bubble with a pin, and then push the air towards the puncture with your fingers.
Wet and Dry Application Methods
Wet Application Advantages:
Wet application is usually better for larger decals. The wet solution temporarily inhibits the graphics ability to adhere to the surface fully, allowing you to lift and move it. Also, air can travel under the decal easier which helps deter bubbles. This allows you time to work with the material on every type of installation.
Wet Application Disadvantages:
When you are removing the spacing tape after the graphic has been applied, care is needed to refrain from pulling the graphic off the surface. Do not wash the area of the applied graphic for a few days until the application solution has had time to fully dry and the adhesive can adhere to the mounting surface properly.
Dry Application Advantages:
Dry application is recommended for small lettering and graphics. When using the dry method, permanence of the graphic is immediate. Therefore, there is a better adhesion of the graphic to the mounting surface for pulling off the spacing tape. This makes it easier to pull the protective tape away from small and detailed designs.
Dry Application Disadvantages:
There are no second chances with the dry method. Once your graphic has been pressed to the mounting surface, there is no way to remove the graphic without damaging it. This means that more care must be taken in the placement and application to ensure that your graphic is straight and free of bubbles.
Preparing to Apply the Graphic
Now that you’ve properly cleaned the area surrounding the mounting surface, spray a light mist of Pro-Bond to each rivet head. This enhances the bond and minimizes tenting over the vinyl graphic.
“Applying vinyl to aircraft is similar to applying vinyl to vehicles,” Duchinsky says. “The biggest issue on small aircraft has to do with all the rivets. You need to do some additional prep work to get the adhesive to set up and bond to the surface than you would with an automobile.”
Next, position the vinyl. Sharpline recommends positioning the vinyl graphic in place on the aircraft with masking or application tape. As an aid for aligning and registering the graphic on the mounting surface prior to application, make register marks on the side edge of the surface with a lead pencil, a marking pen or small pieces of masking tape.
Once you’ve done this, remove the liner and lay back one half of the vinyl graphic against the aircraft. Remove the liner by sharply flicking the graphic edge toward the face of the graphic with the ball of the thumb or a fingernail.
A small bend at a corner or edge will cause the liner to separate from the graphic. Pull the liner away in a continuous motion at a 180-degree angle. Duchinsky warns to always remove the liner from the vinyl graphic rather than the vinyl graphic from the liner.
Applying the Vinyl Graphic
Now comes the fun part. Align the vinyl graphic to the register marks and tack it to the mounting surface with thumb pressure at the corners. (For larger graphics, use one or more additional tack points along top edge.)
Using a felt squeegee, begin application at the vertical center of the vinyl graphic and apply all the way to one edge. Then return to center with overlapping strokes and repeat the procedure, applying to the opposite edge.
If you’ve ever applied vinyl before, then you know you want to avoid bubbles and wrinkles in the vinyl graphic at all costs. That’s because bubbles and wrinkles allow some tenting of the vinyl. Whatever you do, do not squeegee vinyl down around rivets until paper masking has been removed.
Removing the masking
You’re almost done. The next step is to mist the application masking with a water solution. Then allow this to soak for a minimum of two minutes. This will release the bond between the application masking and the face of the vinyl graphic. Then, remove the application masking from the face of the vinyl graphic by pulling the masking back upon itself — always at a 180-degree angle.
If you have your air release tool handy, this is a good time to get it out. Use the air release tool to puncture the graphic several times around the rivet head, then warm the vinyl graphic and form the vinyl over the rivet with a felt squeegee.
Also, inspect the graphic in the flat areas for air bubbles. To eliminate these bubbles, puncture the graphic at one end of the bubble with an air release tool and press out entrapped air with a felt squeegee, moving towards the puncture.
You are almost done. When the entire graphic has been applied, re-squeegee the entire graphic using a felt squeegee.
For Cleaning Graphics with an Over Laminate Film
Use a cleaner designed for high-quality painted surfaces. The cleaner must be wet, nonabrasive, without strong solvents, and have a pH value between three and 11 (neither strongly acidic nor strongly alkaline.)
Hand Washing Exterior Graphics
• Flush the graphic with clean water to remove loose dirt particles. A trigger-type hose nozzle is convenient for this purpose.
• Use a mild liquid detergent and water solution and wash the graphic with a soft brush, rag or sponge.
• Wash thoroughly from the top down.
• Avoid abrading the graphic by scrubbing unnecessarily.
• After applying the cleaning solution, keep steady streams of water flowing on the graphic to wash away dirt particles.
• Rinse the entire graphic thoroughly with clean water, and allow the graphic to dry naturally.
Removing Difficult Contaminants
Some contaminants might remain after following the normal cleaning procedures. Most contaminants can be removed using one of the methods listed below. Other cleaning products and methods should be used only on a customer test-and-approve basis.
To Remove Tar, Oil, Diesel Smut or Bituminous Material
• Wipe with a rag dampened with kerosene, mineral spirits, heptanes, or VM&P naphtha. Do not use other solvents.
• Wash immediately with detergent and water, and then rinse with clean water.
• Avoid abrading the graphic by scrubbing unnecessarily.
• Wipe the graphic with a water-soaked brush, rag or sponge to wash away the detergent and dirt.
• Dry the graphic with a lint-free clean towel.
Thanks again to the team at Adnormous Graphics for sharing their expertise on the installation and maintenance of vinyl graphics on helicopters.