C;That’s why we always ask our clients the temperature they’re baking in to offer them the right product,” he says.
“Painters should look for the elongation of the tape,” Hajoui adds. “They also should expect clean removal of the tape after putting the car in the oven or after putting it outside.” Ask yourself the following questions, Hajoui says: What’s the temperature that I’m going to use to bake? How much time the tape will stay on the car? Is there any specific product that I’m putting on the car? They need to verify if there’s a specific treatment that they will apply to the car, such as UV, Hajoui says. In such a case, they will need a specific tape (UV masking tape).
Tuk S.A. recommends its Master Grade 846 masking tape in applications that involve the high curing temperatures for automotive painting.
Intertape’s Seawright again points to the need for getting a well-defined paint line without leaving any adhesive transfer after removal.
“This is especially important in baking applications or the use of heat to cure the paint,” he says.
Most shops need a product that can stand the elements. Some applications occur in the Phoenix sunshine. Others are done in the high humidity of the Coastal Carolinas. Up North, it’s typical to work against cold mornings and warm afternoons. A key element here, Seawright says, is speed. “The product needs to be removed after a quick bake cycle.”
“The variety of conditions increases the importance of using a premium masking tape,” adds Guck.
Masking Tape Spec Chart
Taping Over Paint Surfaces
Taping finishes over exposed paint presents its own separate concerns to the painter.
“The tapes need to provide complete protection over the painted surfaces,” Seawright says. “Good quality tape will provide complete protection.”
Painting lines is a challenge. Typically, the paint will pull against the hard edge of the tape, and the painter ends up with a stair-step bump on the surface. There are foam tapes with sponge on one side that, in many cases, give good results. But in both cases, the solution is expensive – especially when it involves the labor of sanding.
EZ Edger from Hostar in Norcross, Ga., doesn’t make tape. Rather, they make a tape applicator that folds one edge of the tape under in such situations.
“A lot of good technicians can do it by pinching the tape between their thumbs and index finger,” says Hostar’s Chi Sung Row. “I’ve even seen people use their lips.” However, it takes a good deal of practice to get the technique down. And, on long runs, it’s difficult
“At trade shows,” Row says, “I always have someone who wants to challenge EZ Edger to see who can fold the tape faster. We always win.”
The EZ Edger, Row says, is easy to load. “Some of the old tools were a nightmare to load the tapes through the machine,” he says. Folding tape gives a soft edge with some overspray going under the tape to ease the transition from one color to another.
The folded width is adjustable. This feature allows how much overspray to occur while painting to control the blend. “It also has an option to provide a lifted-edge,” Row continues. “The final stage of the EZ Edger has an option to add more lifting by crimping the edge upwards in a V-shape to allow more blending.” He notes that painters who have never tried the folded edge technique to produce a soft edge are often skeptical of the results.
“It does take a couple of test panels to master the technique and the set-up to produce great results, but the learning curve is very fast,” Row says.
Videos on the company’s website (www.ezedger.com) walk a technician through effective ways to use the tool.
For finishes over exposed paint, Tuk S.A. recommends their blue 830 masking tape.
3M makes a two-layer tape for this application.
“Two-tones, stripes and custom paint applications require a different category of masking tapes commonly referred to as fine-line tapes,” Guck says.
Fine Line tapes have thin, smooth backings designed to create low-profile paint edges. Sharp paint lines are achieved by using fine-line tapes with smooth backings coated with specialty adhesives to prevent paint edge bleed. “Scotch Fine Line 218 is designed for straight line application, and is available in nine narrow widths for a variety of paint striping options,” says Guck. “3M Vinyl Tapes 471 and 471+ are very conformable and are designed for custom paint designs.”
A product like Intertape Polymer Group’s (www.intertapepolymer.com) PT14 is a blue, pressure-sensitive masking tape designed for professional painters. With its fine-structured crepe backing, the company claims it provides “excellent” paint lines, cornering and “unsurpassed” conformability. Another claim is that it will remove cleanly for up to 14 days, even with direct exposure to sunlight and high humidity. Typical applications include masking of glass and metal surfaces, and marine painting applications.
Tips for Great Tape Performance
“Proper surface prep is very important when masking,” says Ted Guck of 3M Automotive Aftermarket.
To clean the surface completely, start with a water-based cleaner to remove water-soluble dirt and follow with a solvent to remove petroleum-based contaminants. Masking tape will not stick to surfaces that aren’t clean and dry.
“Apply long strips of tape; short pieces mean more seams, and seams mean more possibilities for paint seepage,” Guck warns.
Masking tapes must be pressed down firmly across the entire surface to achieve optimal adhesion and avoid edge bleed, Guck continues.
Environmental conditions can also impact the performance of masking tapes. If temperatures are below 60˚F, the adhesive can become firm and will be harder to make stick. On the other hand, with ambient temperatures above 90˚F, adhesives can soften from the heat of the surface, which can increase the chance of adhesive transfer.
Scotch Performance Masking Tape 233+, better known as 3M’s “Green Masking Tape,” is designed to meet the challenge. The green backing is specially treated to hold out water-based and solvent-based products used in collision repair. The special paper backing is strong, yet easily conforms to effectively mask the curves and contours commonly found on vehicles today. The special adhesive sticks to the many different substrates on a vehicle and ensures the tape stays in place even when coated with solvents and heated during the bake cycle.
Last but not least, the special balanced construction of 233+ makes it possible to remove the tape without tearing or leaving adhesive on the surface.
Avoid paint blow-by, bleed-through, adhesive transfer and spending valuable time fixing these problems by using premium quality masking products.
Masking Tape Spec Chart
Curt Harler is a Cleveland-based freelance writer specializing in the automotive, technology and environmental areas. He’s the recipient of the International Communications Association Industry Achievement award for his writing. You can reach him at [email protected].