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Braking
with Tradition The last thing most people think about while driving down the freeway – usually at speeds in excess of 70 miles per hour – is whether their brakes, or those of the vehicle behind them, are any good. Until, that is, they have to slam on those brakes to avoid hitting the vehicle in front of them. The one they are rapidly approaching because they were too busy – talking on their cell phone, reading the newspaper, shaving, putting on make-up, eating, yelling at the kids, or just plain not paying attention – to notice that it was slowing down. In that brief, but very intense, moment of panic, most people spend as much time watching the car behind them getting closer in their rear view mirror as they do watching themselves getting closer to the car in front of them. It’s a fine line: Do you trust your own brakes and reflexes, or trust the brakes and reflexes of the person behind you? What’s it take to stop a 7,000-pound SUV traveling at 80 miles per hour, anyway? Well, consider this: it takes about twice as much as it does to stop the 3,500-pound vehicle for which its brakes were probably designed. Now that’s scary.
Norm is the owner and president of OE Quality Friction of Mississauga, Ontario, a company that manufactures original-equipment-quality disc brake pads for the automotive aftermarket. His specialty is brake pads for light trucks, vans and, you guessed it, SUVs. Of course, OE manufactures pads for passenger cars, as well; but when Norm put together his business plan to start the company a few years back, he saw a growing trend toward light trucks and SUVs. Betting that trend would continue, he chose to concentrate his efforts on that market. It’s a bet that paid off: Light trucks and SUVs currently account for more than 50 percent of all new vehicle sales. Brake pads – or friction materials as they’re known in the business – are nothing new to Norman. For years he worked for Allied Signal Friction Materials, a major supplier of original equipment brake pads to the automotive industry. “I was vice president of engineering at one time, and I was responsible for developing a bunch of OE (original equipment) formulas that are still in production today with the vehicle manufacturers,” he explains. “I ran the operation here in Canada up until about 1992.” That’s when Allied Signal decided there was too much production capacity in North America and Europe. So, because the Canadian dollar was worth about 87 cents at the time and going in the wrong direction, they closed down the Canadian plant. Norman Abbott found himself out of a job. “Systematically, I let 450 people go, got out of the business, got interviewed for a few jobs, decided that age discrimination was alive and well, did a bit of consulting for a few friction companies, then decided that what I needed to do was start a company,” Norm explains. That company is OE Quality Friction. “I got a bunch of people around me – some other guys who had worked at Allied Signal put some money in – I wrote a business plan, went to the banks, borrowed a lot of money and started the company,” he says. Though Norm makes it sound easy, he knew the only way
he’d be able to compete with the “big boys” was to make his own
tooling. Gone are the days of simply riveting pucks of friction material
to backing plates and calling it a day. Today’s disc brake pads are
integrally molded: The friction material is formed to size and bonded
directly to the backing plate under extreme heat and pressure in a single
operation. It’s a method that requires dedicated tooling for each unique
pad.
Rather than fight the math, Norm decided to change the conditions. The key, he says, was to make the tooling in-house, but he didn’t understand anything about NC machinery. “I knew I was going to do this company, but the missing link was the tooling. I decided to get myself educated.” During his consulting days, Norm had run across a
small company in Florida that made some of its own tooling; he decided to
pay them a visit. “They had a Haas VF-3 tucked in a corner which made a
little bit of tooling,” Norm says. “I spent three months standing by
the operator’s side, basically learning about CNC machines. The Haas was
a very nice machine – it performed beautifully. So I convinced myself
absolutely that I was going to come back, take a course in NC programming
and buy a Haas. It was very simple. I didn’t look at any other
machine.”
Though his financing still hadn’t come through, Norm bit the bullet and bought the machine. “I didn’t have a facility to put it in,” he laughs, “so I had it delivered to a friend’s facility, where we got it wired up and running. At the same time, I was taking my CNC course, and I set up the machine and played with it. I had a few scary moments, but finally got to the point where I was proficient,” he says. “In the meantime, we’d found a facility, the bank had given us approval to start the business, the other shareholders came in and we got started.” That was back in 1997. By September of 1998, the company was seriously producing parts, and by 1999, OE Quality Friction was a profitable concern. Today, OE Quality Friction manufacturers more than 220 different part numbers of disc brake pads, and that number continues to grow. “We are right up to date on domestic light truck and sport utility applications,” Norm says. “We’ve got a full line of domestics, and we’re branching into the import car. We’re tooled right up to the 2001 model year vehicles.” The ability to make tooling in-house and react quickly to the needs of the market have been critical to the company’s success. OE is one of only two brake pad manufacturers in North America that makes their own tooling.
A complete set of disc brake tooling consists of a bottom plate, a cavity plate and a punch plate. The bottom plate holds the steel backing plates for each brake pad, the cavity plate sits on top of that to mold the outer profiles of the pads and the punch plate carries the punches that fit exactly into each cavity to form the pad’s top surface. A cavity plate may have as many as 20 cavities, or as few as 8, depending on the size of the pads, and the punch plate will hold a corresponding number of punches. Since each punch has to fit exactly into a corresponding cavity, the typical manufacturing method, Norm says, is to use wire EDM to cut the slugs out of the cavity plate, then machine those slugs and use them as the punches. But OE Quality is far from typical: They machine all of the tooling out of 4140 heat-treated alloy steel plate.
OE further reduces costs and speeds turnaround by “production-izing” their machining processes. “We’ve commonized the external features of all of the tools,” Norm says. “We have canned cycles for all three plates, so we can knock those off probably in a tenth of the time it would take the average jobbing shop. Really all that’s left, then, is reverse engineering an OEM sample.” From the OEM sample, Norm creates the toolpaths in SmartCAM: one to cut the bottom plate, one for the cavity plate and another for the punches. The bottom plate and cavity plate require only two-axis pocketing to cut the profiles of the backing plate and the friction pad, respectively. The punches, however, often require 3D work, because many modern disc brake pads have chamfers on their leading and trailing edges to reduce squeal and chatter. Most manufacturers cut these chamfers after the pads have been molded, but OE takes a different approach. “We mold in the chamfers,” Norm says, ”which is unique in our industry. We take advantage of the 3D capabilities of the Haas to cut the chamfers into the tooling.” Since all of the cavities in a particular set of tooling are identical, as are all of the corresponding punches, Norm only has to create the toolpaths for one location. This done, he hands off the programming and machining duties to Nabil Khanania and Dan Beaudin. Nabil has been with OE Quality from the start; in fact, he was the company’s first employee. “I met Norm when I was taking the CNC course at Humber College” (a local community college), he explains. Dan is a graduate of Humber College, as well, who was recruited by Nabil. The pair currently split their time between making tooling and providing support for the rest of the plant. Nabil takes the toolpaths Norm has created in SmartCAM and turns them into complete machining programs for each plate. For example, if a set of tooling has 12 cavities, he will write a sub-program to cut the profile of a single cavity. “It’s one profile, one layer,” Nabil says. “I make that layer three or four times depending on the thickness of the part, then I pick up that sub-program and give it another work offset to cut each of the remaining cavities. All of the pockets are measured from the center of the fixture,” he explains. “We specify an X, Y coordinate for each of the pockets and run the same sub-program at each location.” In essence, the machine just cuts the same profile over and over at different depths and locations.
Each tooling plate starts life as an 18- by 16-inch piece of hardened tool steel that has been squared and ground flat by the supplier (the added expense is well worth the reduction in machining time). Plate thickness varies from about 5/8 inch to 2 inches, depending on the size of the brake pads being made, and whether it’s a base plate or cavity plate. All of the external features and common locating holes in each plate are machined using canned cycles, and then the features specific to each plate, such as cavity profiles, are machined. The punches start out as pieces of tool steel 20 inches long by the width of the punch. “It’s like a rack of ribs,” Norm says. “We do all the drilling and reaming in that strip while it’s still in one piece. Then we chop it up into sections that go straight onto a fixture. That way we don’t spend time unnecessarily facing and squaring pieces of steel. As long as we’ve got one ground flat surface that’s drilled and reamed for dowel pins, it just drops onto the fixture.” Each punch takes about 45 minutes to cut, and comes off the machine as a finished part. “We do a slight bit of deburring,” Norm notes, “and it’s finished – no hand work at all.”
“These are five-daylight cure presses, so we’re cooking four part numbers at a time, and the fifth daylight is used as a heat-up daylight for the next set of tooling. Because all of our tooling is common,” Norm adds, “when the tools are closed, you can’t tell one from another. It could be running a three-cavity truck part, and underneath it would be a 20-cavity rear brake for a Beretta. The tooling is constantly going in and out of the press, and every six minutes or so, you get a set of parts.” Once molded, the brake pads are ground to a uniform thickness, painted, assembled with any additional hardware required and boxed for shipping. OE currently runs two shifts per day on the production side and a single shift in tooling. Their 14,000-square-foot building is now filled, and they’ve added a third cure press to keep up with demand. According to Norm, Nabil and Dan have become so proficient at producing tooling on the Haas that the “machine now outpaces the organization. We could pump out a lot more tooling, and the machine could run more, but our infrastructure couldn’t handle it,” he says. “We’d have to double our people in the office!” That’s an enviable position to be in for such a young company. And though age discrimination may be alive and well, in the case of Norm Abbott, it looks like this old dog is teaching the industry some new tricks.
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