Features Fabrication Innovations
Rockin’ rollforming

Rollforming is a process normally associated with fast mass production of relatively simple, linear shapes in metal.

Rollforming is a process normally associated with fast mass production of relatively simple, linear shapes in metal. Coil aluminum or steel is fed into a series of dies, rollers, punches, notchers, presses, welders and saws and strips of cut-to-length product are continuously discharged at the other end of the line. In the fenestration industry, rollforming processes have provided such commodity items as C-channel, muntin, grille and pencil bar, sash reinforcements and patio door track for decades. If you ask most people, little has changed in this field of metal fabrication in living memory. 

An extensive library of dies gives RPM the ability to quickly come up with rollforming processes to meet custom demands. Because creating new dies is one of the biggest costs in rollforming, this huge inventory can help keep costs down.

But RPM Rollformed Metal Products in Concord, Ont., and its executive team of vice-president Yousif Abachi and sales manager Vince Porcelli, think they can offer more. Having already pioneered a thermally broken aluminum spacer – the well-known Climatech product – the RPM team is looking for more challenges from the glass industry to create new channel profiles with custom contours, special bending characteristics and exotic materials.  Abachi says their combination of experienced staff, long exposure to the industry and engineering expertise gives them the flexibility to take on the kinds of unique custom projects other rollformers have long shied away from.

RPM’s journey to innovations started with previous owner Gunter Berdan’s invention of Climatech three years ago. Climatech IG spacer bar incorporated plastic into the rollformed aluminum or stainless steel profile, creating a thermal break and allowing IG manufacturers to achieve a warm edge with the structural integrity of metal. Finding the right resin to integrate into the spacer bar was challenging, but the real innovation was in the process design. “The key piece is doing operations that would otherwise be done as a secondary operation,” Abachi explains. “You don’t really impact the speed of the line in feet per minute, but you get more processes done. In this case, the metal is bonded to the plastic in-line. All the pre-punching and holds are done as an in-line process. So it is very cost effective and eliminates secondary operations as much as we can.”  Porcelli reports that window fabricators have found the Climatech spacer easier to bend than some other products, which makes the assembly process more efficient. The combination of function and low-cost, high-speed production has made Climatech RPM’s flagship fenestration product. But Porcelli and Abachi are sure there is more out there.

Much of the rollforming that now takes place in the fenestration industry is by companies who are primarily fabricators and invested in a machine to satisfy their own needs. RPM’s difference is the company is a rollforming specialist first, serving a wide variety of industries from storage to automotive. Berdan recently sold the company to a larger group that includes tool and die, hydraulics, mould-making, precision grinding and automation shops. So RPM has a wealth of metalworking experience to draw from, and not just in aluminum. Yet the company’s experience with the fenestration industry is now so extensive, it is seeing some significant advantages when designing new processes for new products. “With the vast library we have amassed of punching and rollforming and tooling, we have noticed that a lot of guys will use similar components,” Porcelli says. “Window guys tend to use similar lineals, and because we have created a library we can now go out there and say we may very well have all the tooling and punching requirements in-house. So that helps keep the costs down for the market.” Creating new tooling for a specific shape in a rollforming process is probably the single most expensive element of setting up a new line, and a major reason why most rollformers dedicate one line to one product and never change it. With a stock of established, fenestration-related tooling to choose from, RPM has put itself in a better position to serve the industry.

If making tooling is the single most expensive element of changing over a rollforming process, the various elements involved in setting up and commissioning a line for a job probably add up to the greatest chunk of the overall cost. For a rollforming line to function correctly, dozens of separate tools, guides, switches, sensors, and materials need to operate in tandem with perfect timing and minute positioning accuracy. Every adjustment affects several other settings up and down the line. Even with modern computer controls, calibrating a rollforming line is more of an art than a science. In a shop with inexperienced operators, or operators for whom running the rollform line is not their primary occupation, changing the setup on a rollforming line is something to be avoided at all costs. Days of labour are often involved, and weeks if something goes wrong. This is where RPM’s identity as a rollforming shop first really pays dividends and puts it in position to try some new things. “Over the years, RPM has developed a very strongly skilled setup staff,” Abachi says. “Not only do we have 14 lines here with the 15th coming, but within those 15 lines none of them are dedicated. Some of these lines see changeovers two or three times per week. We are very flexible and agile and have a very strong team on the backs of our setup personnel rather than operators only.” One area where experience gives RPM a distinct advantage is in pre-punching. “The process of pre-punching involves servo feeders, like stamping,” Abachi explains. “You need to add a pre-punch press and then integrate the whole line together. So it is not just about putting the line in place. It is about having people who can set up these lines, achieve a stable process and get a repeatable accuracy from hole to hole.” Abachi uses the example of changing coil thicknesses, a common challenge in the industry. “If the next master coil has a thickness variation, that will drive changing the settings from A to Z – from the pre-punching, through several feeders, the pressures, the rollformers and the clearances as well. The ability to do that quickly is not something that came over night. That is something we have developed over the years.”

It is difficult to see how the tool could have made such a fold without. The ability to work with steel – even heavy steel up to seven gauge – opens on pre-punching thicker steel and heavier gauge material,” Abachi admits.

Abachi is eager to help fabricators develop new products or improve old ones. “We have gotten involved in the development phase when the customer has a theoretical sketch of a more complex channel and they pass it by us so we can give them feedback,” he says. “We can tell them what changes would take that project that requires $100,000 in tooling down to a project that requires $2,000 or zero tooling. We have found that is very much appreciated for two reasons. One, it eliminates costs. The second thing is lead time because if we do have standard tooling that can achieve a certain shape we could be up and running within three days if we have a slot available on the machine.”

Here comes the sun
RPM sees great potential for rollforming processes in making solar energy components. Photovoltaic panels tend to be larger and heavier, making steel channels and brackets more desirable. Solar energy collectors often need channels and framework for wiring and electronic panels, as well as punched pieces for mounting and attaching external equipment. RPM has picked up work on some large projects of this kind both in Canada and the U.S., and hopes to expand its portfolio in this area.  

Rollforming processes are especially suited for the following components and processes:

• Z purlins
• C channels
• U channels
• punching
• notching
• cut-to-length