A Look at Custom Masking

Masking may well be the single-most unappreciated aspect of finishing. At best, many shop managers perceive masking as a necessary evil, something that must be done before the "real work" can begin. At its worst, it can be a frustrating and time-consuming nightmare. And while the introduction of robotics, process controls and automated systems have steamlined many aspects of finishing, masking remains a labor-intensive process.

But does it have to be that way?

"The reality of masking is that done right, it can provide an incredible competitive advantage," says Ron Phillips, president of Hi-Tech Flexible Products Inc. "A lot of folks need to accept the fact that painting and electrocoating have become commodity businesses. In that regard, effective use of the right masking product can give finishers an edge."

Phillips should know. As a supplier of custom masking solutions, his Jackson, MI-based company has supplied masks to thousands of customers - including GM, Toyota, Chrysler, Denso, Visteon, Delphi and Metokote, to name a few - in its 17 years of business.

Hi-Tech Flexible Products Inc. is representative of a growing facet of the masking industry - customized masking. Rather than buying a generic plug or cap and hoping that it fits the part - sometimes the equivalent of fitting a square peg into a round hole - finishers can take their part to a custom masking supplier and come away with a mask designed exclusively for that specific item.

Hi-Tech has purposely stayed out of the stock masking market, a move the Phillips says was intentional. "We wanted to focus on one thing - custom masking - and become the master of our craft. If we're spending part of our time selling stock caps, plugs and tapes, we're taking away from our core expertise."

For his part, Phillips believes that custom masking will play an important role in the future of the finishing industry. "There's always going to be a role for stock materials," he says. "But from our perspective, there are a number of factors that favor the solutions made possible by custom masking." According to Phillips, these include:

• Ergonomics: "If somebody is spending two minutes struggling to put a mask on a part, that's time wasted," says Phillips. To that end, custom masking suppliers are thinking as much about the ease of applying or removing the mask as they are the performance of the mask itself.
• Part Design: "As the software used by designers continues to evolve, parts are becoming increasingly complex," says Keith Bice, custom solutions manager at Hi-Tech. "As a result, we're seeing a much greater need for custom-made masks than existed 10 years ago." And because it's rare for manufacturers to take masking/finishing into consideration when they are designing a product (a symptom of the ongoing disconnect between the design and coating stages), the use of custom masking solutions can result in a time-savings for the finisher… not to mention a lower degree of frustration. "We're typically approached after [a part has been manufactured]," says Phillips. "Our thought-process is 'let us worry about it so you don't have to.'"
• Value Added: Because there is a tendency on the part of some to view masking with a bias, suppliers like Hi-Tech are constantly exploring ways to build greater value into their products in an effort to reduce waste, minimize labor handling and improve part quality. Phillips says those ideas might include using high-quality materials that can be used several times over, designing the masks so as to prevent powder "bridging" on parts (the tendency of powder coating to build up along the edge of a mask, requiring a secondary operation to remove it) and incorporating air release "vents" into the mask so that they do not pop off when the part is cured. In Hi-Tech's case, the company has taken the value-added approach a step further, introducing conductive masking to its repertoire (see Sidebar below).

Although customized masking - on the face of it - tends to be more expensive than stock materials, Phillips contends that the potential improvements in labor costs, line speed and part quality more than compensate for the cost difference. "In terms of embracing the technology, we've definitely seen the most interest from companies that we would define as 'big picture' people," he says.

At Hi-Tech Flexible Products Inc., the process of designing a custom mask is a relatively simple one. Typically, the customer provides an example of the part to be masked. An engineering specialist will have a brief conversation with the customer to confirm their needs and address any ancillary issues. At that point, the design department develops a 3-D model of the mask using state-of-the-art CAD/CAM software. The design can be shared with the customer over the Internet. After the design has been approved, the production department creates a mold using CNC machinery. That mold then becomes the basis for the masks themselves, which are produced from a high-grade Dow Corning silicone. Depending on the complexity of the part, there is usually a brief period during which any kinks are worked out and the mask is fine-tuned.

At the Crown Group (Detroit, MI), one of the nation's leading finishers, customized masking is used in the application of wet spray to parts - including axles, brake cables, companion flanges, calipers and rotors - for a large automaker. Plant Manager Len Ulatowski says he opted for custom masking because of the complexity of the parts he was working with. "You're going to need a custom-made mask with a lot of these parts," he says. "We initially did some generic masking on the companion flanges, but ran into problems, so we switched to customized masking. On other parts, we knew just from looking at it that it was going to need a custom solution."

Ulatowski - who worked hand-in-hand with Bice as the masks were developed - says he's been pleased with what customized masking in general - and Hi-Tech in particular - has brought to the table. "I don't think we could have painted these parts without their assistance," he says.