Looking Closely at the Part to See Clearly
Two fabricators take two parts and redesign them to save money
By Mark Langlois
Combining a customer's design with a job shop's specialty led a Michigan aluminum firm and a Kentucky aluminum extruding firm to new designs that lowered costs and improved quality of key military and commercial products.
In Kentucky, Cardinal Aluminum replaced a two-piece precision steel assembly with a one-part extrusion that saved money and maintained strict quality standards.
In Michigan, the military build-up that started after 9/11 led Fab Masters Company Inc., to a new part, a nearly flat aluminum bar extrusion that today sits between the front seats of large military personnel carriers.
The aluminum extrusion process involves heating a round bar of aluminum called a billet to between 800 degrees and 925 degrees Fahrenheit, a temperature hot enough to force the metal to flow under pressure through a die. The presses involved are rated by pressure in tons, in many cases from 100 tons to 15,000 tons. The amount of pressure required to create a shape is determined by the size of the hole in the die. The extrusion takes on the shape of the die much like toothpaste takes the shape of the tube opening. The length and size of the part depends on the shape of the die and the size of the billet. Once the extrusion cools, it is stretched and then finished to meet the customer's requirements.
Aluminum growth remains strong
Fab Masters Company Inc. started out in 1984 humbly enough in a one-car family garage, on a $1,500 tax refund, calipers for quality control, a bench mill, and cutting tools. By the early 2000s after expansions, contractions, and hard work, Fab Masters employed roughly 120 people in a 100,000-square-foot factory, still located in Marcellus, Michigan. It is building an 11,000-square-foot addition that will give its warehouse drive-through truck loading and unloading, plus it will bring material staging closer to the process starting point.
"Aluminum is a growing market in the U.S. and we've added capabilities like cutting, welding, and punching, along with a network of finishers and vendors to fill a market need," said Sam Cropsey, Fab Masters sales manager.
Ducker Worldwide, a Detroit-based market research and strategy firm, reported 30 percent growth is expected for aluminum products in automobiles over the next 10 years. "... rolled and extruded products have been particularly identified as replacing steel in many instances," said Wouter Vogelaar of Ducker Worldwide, in releasing the study commissioned by the European Aluminum, an association formed in 1981 of European firms working in aluminum. The report and release is available on the Ducker Worldwide website. The automobile industry is turning to aluminum because it is lighter than steel and is strong, thereby contributing to lighter-weight cars and less air pollution.
"What is most exciting about these results is the growth the industry is realizing overall, especially in automotive applications," said Jeff Henderson, president of the American Extruders Council, speaking about annual growth in aluminum sales. Henderson added, "Even though our largest end use category, building and construction, grew a modest 4.5 percent last year (2015), it was the fourth consecutive year we've seen increases."
Henderson was speaking in a council press release that said domestic consumption of aluminum extrusions in the United States and Canada totaled an estimated 5.11 billion pounds in 2015, an increase of 4.5 percent over the 4.89 billion pounds reported in 2014.
Why fix a part that isn't broken?
To build one product for a military customer, Fab Masters started with an extruded flat aluminum bar. Then it took round aluminum bar stock and drilled a hole down the shaft. For each finished part, it cut three inch-long bosses from the round bar. It welded those bosses to the flat aluminum extrusion. Then it CNC machined screw holes into the flat extrusion.
The customer was happy with the part and bought 25,000, but inside Fab Masters, workers were unhappy with their part. Workers kept trying to figure out how to improve it. "Old school principles–sometimes you apply them and get better results," said Cropsey.
"They (the customer) were satisfied with what we were doing. There's one of them in every vehicle. It goes down by the gearshift," said Cropsey. He said he doesn't know what it does. "Welding the bosses to the bar caused the bar to heat up and warp. Welding was costly and time consuming and caused some deformation. The bosses also had to be produced in an additional operation. It was a tough project due to the welding, machining, and materials involved."
The numerous steps created a wobbly part with welds to inspect. The welds required extra quality control checks. That costs extra money.
Workers didn't like the process because the metal bar warped and wouldn't always sit flat. The welds that held each of the round plug-like bosses in place were so bulky that in some cases, they interfered with holes Fab Masters drilled through the flat part. Welds had to be checked through destructive testing or non-destructive testing. Each boss cost roughly 45 cents to make, not including the cost of welding.
"What if we change the process?" asked workers who wanted to improve the part.
Workers turned to one of Fab Master's specialty processes, CNC machining. Instead of cutting the round bar and welding it to the flat extrusion, they decided to start with a bigger extrusion and mill away the extra metal and create the round bosses by machining them out of the extrusion. "The extrusion only required a CNC process," Cropsey said. The aluminum ground off the extrusion was recovered and reused. "You get 50 percent back on your recycling."
"We made the bar and three bosses in a one-piece extrusion instead of four separate parts that needed to be welded. We just needed to machine away some excess aluminum, and it eliminated the three added parts and the welding. Plus, the part no longer had warp and deformation from the heat of welding," Cropsey said. They made the one-piece extrusion a tiny bit larger than required so they could machine a polished surface onto each part. "We designed the extrusion needed and presented the concept to our customer for review."
Customers happy with a part don't like to change horse mid-stream, but in this case, the new process created an improved part. The customer inspected and approved it.
What started as a four-part assembly requiring extrusion, welding, and CNC machining, turned into a single part that needed extrusion and CNC machining.
Fab Masters (www.fabmasters.net) made 120,000 pieces since 2002, one per vehicle. The first 25,000 were the welded version, and all since are the new design. The welded version cost $15.50. The improved part cost $12. The process change saved the customer $3.50 on 95,000 pieces over the last 12 or 13 years. A total of $332,500 in part cost savings. It helped Fab Masters, too, Cropsey said. It increased Fab Master's profit margin on the part a little, Cropsey said.
"We're good at problem solving and finding solutions," Cropsey said. "We listen to the needs and problems customers have to find solutions to those needs and problems."
Can Cardinal make an aluminum piece to replace steel?
In Louisville, Kentucky, a Cardinal Aluminum Co. salesperson was shown a part by a customer after a year of knocking on its door.
The steel part was attached near the top of a table saw. It has gear teeth on one side used to adjust the guard that holds wood in line for cutting. The customer had a problem. It had a steel gear system that controlled the guards, but it was an assembly of two parts. It was expensive in steel, and it required assembly, so the customer asked if Cardinal could come up with an aluminum extrusion that would be as accurate, would not fail, and would cost less.
"If it's crooked, they're not happy," said Nathan Floyd, vice president of business development at Cardinal Aluminum Company. Gears attached to the crooked part would jam. "If they have a big piece of cherry on the saw, the part can't fail. If it's off just a bit, it jams."
Cardinal (cardinalaluminum.com) started out in 1946 with the founder making aluminum extrusions for window frames and awnings. It is now owned by the family's second generation. Cropsey said the founder realized almost immediately he needed to offer extra services beyond a simple extrusion.
Cardinal's strength, Floyd said, "is our ability to help a customer all the way from designing the part through all the different operations, all the way to the final packaging." By "all the way to final packaging," Floyd meant the in-house finishing steps Cardinal offers, including anodizing, powder coating, in addition to designing and engineering a part. Its finishing steps include brushing, polishing, and acid and caustic etching.
Cardinal's fabricating capabilities–ranging from cutting and milling to drilling and deburring–offer customers "more design options than you can think of," Cardinal states on its website. "You aren't limited to simple drilled holes and square cuts. You design the part to work the way you want it to and Cardinal will provide the fabrication techniques."
Under the heading, "Fast Response to Design Changes," Cardinal states on its website, "Since little or no 'hard tooling' is required, you can move things around, change sizes or shapes–even in the middle of a run–while eliminating additional tooling costs and work center set-ups. It's also a cost-efficient way to prototype and get your product to market faster."
Fabricating Options are In-House
Other finishing steps and fabricating options include color fidelity and consistency, as well as cutting, countersinking, assembly, milling, mitering, notching, punching, reaming, routing, slotting, and tapping. Floyd was quick to clarify there is a single fabricating option Cardinal does not do in house–silk screening.
Powder coating might sound like a weak coat of paint, but Floyd explained, "Once it's on there, if you've followed all the proper steps, you can hit the aluminum against a post and the heat treat just bends with the aluminum and the paint won't come off. We found powder to be hugely more durable than wet paint and more environmentally friendly than wet paint because it has no VOCs (Volatile organic compounds). We do it right here in house. It's like painting your house. If you do the surface prep, you sand it and clean it, the paint will last."
Cardinal's guiding principle since 1946 has been, "We take total responsibility for the end product, from die to delivery," according to the company website. Cardinal said most damage to extrusions comes from handling damage, but Cardinal reduces that to almost zero because handling of aluminum is automated on conveyors. "With our automated extrusion lines, these problems are virtually eliminated."
Cardinal is an aluminum extruder exclusively. The company makes window frames, door frames, show doors, display frames, and other extrusions. It works exclusively in the 6000 series of high strength aluminum, and has since 1946. It operates two plants in Louisville with roughly 400 workers and 250,000 square feet of factory space.
Floyd said that Cardinal personnel came together to figure out how to take an aluminum extrusion made of 6005A high strength aluminum alloy and stamp the gear teeth into it so precisely that it would not fail.
"That's why they were buying it in two pieces. Punching it was hard," Floyd said.
"We were able to figure out a production method to extrude and punch it from one piece of metal. A number of things came together–our personnel, our experience," Floyd said. "What used to cost the customer $9 each, Cardinal sold for $6 each. We had to give the customer what they needed, using the alloy they needed at the cost they needed."
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