Volume 36, Number 4, April 2001


Triple Play

Manufacturing Multiple Cavity Spacer Systems

by Art Klukas and Ken Shelbourn

In many lines of work, painstaking attention to detail is routine, and usually critical to an exemplary finished product. Precise movements, in the correct order, can be absolutely essential, as is following instructions. Think of your surgeon, dentist or even the automotive assembly worker who put your car together.

Such is the way of life for decorative insulating glass (IG) makers. The process for glazing a decorative IG unit —whether it’s for a window- or doorlite—can be an exacting process, thanks, in large part, to the use of multiple cavity spacer systems, or “triples.”

Triples have been the spacer system of choice among decorative IG makers for many years running. The two balanced air spaces help raise R-values considerably while protecting decorative lites and delicate welding from the environment. Of course, manufacturing them can be a challenge. The trick is to balance the need for top-class aesthetics, superior thermal performance and efficient internal production processes successfully.

Beauty is in the Eye of the Beholder

Aesthetics are the driving concern for decorative IG makers. Achieving a lite that is architecturally-arresting is the ticket to higher margins. Unfortunately, many IG makers have discovered that nothing can ruin the overall appearance and value of a decorative lite—and their reputation with a window dealer—than unseemly, inconsistent spacer placement. This is especially true when it comes to triples. Ensuring a consistent, uniform sightline begins with the right assembly process.
For the past 14 years, Medieval Glass Industries, located in Delta, British Columbia, has been manufacturing multiple cavity decorative IG units. According to Medieval’s Michael Wilson, the company originally used metal spacer bars filled with beaded desiccant and sealed with a polysulphide sealant. “It was a system riddled with problems,” said Wilson. “We manufacture a lot of custom and irregular-shaped units, and inconsistent placement of the two metal spacers on each side of the decorative unit was causing costly mistakes and slowing down our production.”

Medieval eventually found a solution with a warm-edge, butyl spacer system, which eliminated the company’s need for multiple parts and processes. As a result, production efficiencies increased.

No two words cause decorative IG makers to squirm more than “seal failure.” Yet, when it comes to the use of traditionally manufactured triples, seal failures are an unavoidable by-product for too many manufacturers. With conventional triple spacer systems, the primary culprits are numerous: human error during fabrication, multiple bondline surfaces, the use of materials that are incompatible, the list goes on and on. Add to that evolving building code regulations and a volatile energy industry, both of which have sparked renewed interest in developing more stringent standards for sealant durability and thermal performance.

How are decorative IG makers to respond and decrease potential liability? The answer will vary among manufacturers. Some might need to consider a spacer system that reduces the number of bondline surfaces, thereby reducing the potential for seal failures. Others might be best served by developing a more formalized training system for employees. But a good place to start is a thorough review of your assembly processes. Where are the breakdowns in the system? Could your line’s configuration be having a possible effect?

Those are the type of questions Trimlite Canada Ltd. asked when it began manufacturing multiple cavity decorative units more than 18 years ago. According to Trimlite’s Doug Schick, the company benefited greatly from taking the time to review internal operations and research spacer options. “We are proud of the integrity of our sealed units and our ability to offer the consumer a seal that’s durable from day one and for years to come,” he said.

Production Efficiency
Decorative IG makers are on the hunt for a better, more efficient mousetrap in terms of manufacturing … with good reason. Simply put, the conventional process of manufacturing triples is costly and fraught with pitfalls. Cleaning and recleaning glass requires double, sometimes even triple, handling. Inserting corner keys, loading desiccant, assembling the spacer and applying the sealant, allowing for cure/cool time and the cleaning and stacking of finished units all demand intensive labor and material needs.

Simplifying assembly processes can lead to a number of beneficial results including reduced cycle time, decreased potential of human error and better overall margins. An important partner in helping you review your options and achieve better results should be your spacer supplier. When Specialty Building Products Ltd. of New Westminster, British Columbia, went shopping around for new suppliers, the company’s David Townsend said value-added customer service was high on the priority list.

“Just delivering the best spacer available wasn’t good enough in our eyes,” said Townsend. “We wanted a supplier that would be an extension of our staff and help us realize greater and greater efficiencies. We didn’t stop shopping until we found what we wanted. As a result, we run a simpler, more efficient plant these days.”

Decorative IG manufacturing is a precise exercise, but it need not be a painful one. Keeping a vigilant eye on aesthetics, durability and performance and internal production processes are the keys to success.

Art Klukas is a senior sales representative for TruSeal Technologies in Western Canada. Ken Shelbourn is a technical specialist for TruSeal Technologies Technical Services Group. Fenestration Focus appears quarterly.


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