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Vehicle seat manufacturer rolls with the changes

Moving forward with tube laser cutting

Unless you’re Amish, you probably don’t commute to work by hitching a horse or two to a buggy, snapping the reins, and settling back for a trip at a leisurely 8 to 10 miles per hour. A horse-drawn wagon sounds idyllic and hearkens back to a simpler time, but this travel mode has a few drawbacks, not least of which is comfort. Buggies generally are enclosed to provide some protection from the weather, and leaf-spring suspensions are common, but they aren’t known for their luxury.

While the automobile emerged as the direct replacement for the horse-drawn carriage, the buses and trains used for mass transit systems achieved a prominent and growing role in many cities. The American Public Transportation Association reported that Americans used mass transit for 10.7 billion trips in 2013, the highest level in nearly six decades. The steel and glass cabins provide protection from the elements and shelter commuters in comfort while allowing them to relax, read, work, or listen to music, free from the inconveniences associated with the horse-drawn buggy.

As far as the interiors are concerned, buggies, buses, and trains have little in common. Each is equipped with seats, and that’s about it. Few know this as well as the staff at Freedman Seating Co. (FSC), founded by Hyman Freedman more than 100 years ago. The buggy market was Freedman’s target, and his products were so successful that he was awarded an honorable mention at the 1892 Columbian Exposition (World’s Fair).

The buggy market would fade within a few decades, but Freedman didn’t give up. The company simply transitioned to the mass transit market. The use of trams, first powered by animals, then steam, and then electricity, had been on the rise since the middle of the 18th century. Buses would eventually overtake trams, while trains and shuttles would fill other roles, but regardless, public transit was here to stay.

Old Concepts, New Technologies

When Hyman Freedman founded the company, his focus was on the rider’s comfort, and this hasn’t changed. However, more than 100 years later, the process of making a passenger comfortable is much more complicated. Freedman’s simple cushion has evolved into a sophisticated seating system, one that provides comfort and crash restraint. They are available in rigid or reclining, and many are available in stowable versions, flip-up or foldaway. Accessories include flip-up armrests, map pockets, foot rests, snack trays, cup holders, pillow-style seat, pillow-style headrest, lumbar support, integrated child restraint system, and grab rails. Options include low, medium, and high seat backs; three-point seat belts; wheelchair restraints; stop button; and additional features that comply with the Americans with Disabilities Act (ADA).

Among the simplest, yet most versatile, is the company’s Go Seat. It is shipped without frills, but built so that optional items can be added in the field. At the top of the ladder is the company’s Corporate Collection, which consists of premium seats—luxurious seats with a leatherlike vinyl covering. It also offers many types in between.

Despite the variety of styles, options, and accessories it offers, the company—like all suppliers involved in the transportation industry—is under constant pressure to reduce its products’ weight, which reduces the vehicle’s fuel consumption. At the same time, FSC needs to maintain or improve the padding so it doesn’t sacrifice passenger comfort; decrease the backrest thickness, which leaves more knee-to-hip room for the passengers; and maintain the necessary frame strength to comply with federal motor vehicle safety standards.

The simple shears and sewing machines used to make cushions in the early days have modern counterparts and are augmented by a small fleet of industrial machines for making the substructure.

Bending Round and Rectangular Tube. “Every seat requires a frame, and we make about 90 percent of the frames in-house,” said Shlomo Bar-Sheshet, Freedman’s manufacturing engineer. The company uses 7⁄8-in. to 2-in. round tubing, 1.0-in. by 1.0-in. square tubing, and rectangular tubing up to 3 in. by 4 in., in thicknesses from 20 gauge to 7 ga.

Seats are symmetric, so the company does quite a bit of work with twin-head benders (see Figure 1). The twin-head style is fast and consistent, but it’s limited to simple bends that don’t need the internal support of a mandrel. FSC augments this with a CNC rotary draw bender. The CNC unit’s programmability gives the company the flexibility to make complex bends, a critical capability in offering the variety of seats needed to stay competitive in this market.

Figure 1
For fast processing of simple, repeated bends, Freedman Seating Co. uses twin-head benders (top), which handle most of the 1,000 seat frames the company manufactures daily. It also uses a CNC rotary draw bender, which helps with complicated bends and new-product development (bottom). Because the company processes about 2 miles of tubing every day, the pace is brisk. An autoloader on the twin-head bender reduces cycle times, and stacked tooling on the rotary draw bender reduces tooling changeover times.

Cutting, Machining, Drilling. The company uses various end cuts, holes, notches, and piercings to turn raw tube into seat frames and related components. The company used to perform these operations at several stations using saws, drills, punches, and machining centers. Some years ago it combined these activities in a single workstation when it invested in a tube laser cutting machine.

The benefits were many. It reduced the number of part handlings and eased the work flow through the shop. It also made part tolerances tighter by eliminating the stacked tolerances that come from carrying out a series of fabricating steps on a series of machines. However, this was just a start.

“The tube laser machine’s ability to make intricate and complex cuts provides us with opportunities and ability to be more creative and innovative with design ideas,” Bar-Sheshet said. This allows new designs and lets the engineers combine parts, reducing the number of individual components the company handles. In some cases, the company’s engineers have redesigned mating components to use tabs and slots, thus reducing the need for welding fixtures. This eliminates the time and costs associated with designing, fabricating, and storing them. The company is financially stronger because it is able to reduce work-in-process (WIP).

The company also has found that using a tube laser helps get new products to market more quickly because it doesn’t rely on hard tooling, which can have long lead-times with significant cost. The laser also makes part changes easy for the same reason—a change in a feature’s shape or size requires some programming time, not new tooling.

“It allows us to keep moving forward,” Bar-Sheshet said.

All of these advantages eventually can lead to a new work flow problem, a bottleneck, if a fabricator relies on a single workstation too heavily. When FSC noticed this starting to happen, it began researching the possibility of a second tube laser machine. In addition to moving existing equipment and remapping the work flow to incorporate a second laser, the company had a big choice to make: CO2 or fiber.

The company’s first laser purchase was a CO2 type, which creates a laser beam by pumping energy into a mixture of gases, chiefly CO2. Fiber laser technology, which generates the laser beam by exciting a fiber in the laser resonator, has emerged as a contender recently, and Bar-Sheshet has given both types serious consideration.

The first factor is cutting capability. The fiber laser has a shorter wavelength than a CO2 laser, which provides different heat absorption characteristics and therefore different cutting characteristics.

“Fiber lasers are faster on cutting thin-gauge material, but slower in some cases if the material is thicker than 11 gauge,” Bar-Shehset said. In addition to the cutting speed, another concern is edge quality as the thickness increases, he said.

Safety is another critical concern. “A fiber laser must be completely enclosed while it’s operating because of the light frequency,” he said. If the company planned to use an autoloader, this wouldn’t be a concern, but FSC plans to load the machine both with an auto-loader as well as manually.

Another big concern is the cost. Comparing two machines’ price tags and estimating the operating costs can be complicated, but it’s necessary because a decision like this hinges on both the initial investment and the amount it costs to produce the most common parts on the two machines. In a comparison of two machines of similar wattage, fiber lasers tend to cost more to purchase but less to operate and maintain than CO2 lasers.

Another important concern is the amount of time needed to perform routine maintenance, which constitutes downtime. Fiber lasers are less complicated than CO2 lasers, so the maintenance intervals tend to be longer and the downtimes tend to be shorter.

In the end, despite the attractiveness of fiber laser technology, FSC’s analysis determined that a second CO2 laser would be the better investment.

Then and Now

The seat cushion manufacturing company that Hyman Freedman founded in Chicago all those years ago actually has a couple of things in common with the modern version of his company. It’s still in Chicago, and it still does its own upholstery. The latter is a rarity in this industry, Bar-Sheshet said. It works to the company’s advantage, giving it quite a bit of control over the entire seatmaking process, thereby ensuring quality and short lead-times.

He certainly wouldn’t recognize the markets. In addition to its main targets, bus and rail, FSC makes seats for trucks, commercial vehicles, and specialty vehicles. This is a far cry from the horse-and-buggy days.

He would recognize the spirit of the company. It prides itself on innovative designs, high-quality products, top- notch customer service, and timely deliveries. The company’s recent revenue growth is evidence that it has earned this reputation, just as Freedman won an honorable mention at the World’s Fair in 1892.

The Business Side of the Mass Transit Business

Shlomo Bar-Sheshet, manufacturing engineering manager at Freedman Seating Co. (FSC), explained that the bus and rail industries are a bit like the automobile industry: The OEMs make some of the components, but mainly they do assembly, relying on a network of suppliers for everything from headlights to tailpipes. Suppliers such as FSC don’t advertise directly to the municipalities or companies that purchase buses, shuttles, or trains; they work closely with builders, consultants and users. This, coupled with the fact that the seats are one of the last components that are installed in a vehicle, means that FSC’s fortunes rise and fall with the timeliness of its deliveries and the quality of its products. Over the last decade and a half, they have been rising.

“We’ve had tremendous growth over the last 20 years,” Bar-Sheshet said.” he said. Some of this growth has come from its traditional markets, small-, medium-, and heavy-duty transit, as municipalities invest in mass transit systems, he said. He also credits the company’s sales staff for branching out and selling seats into new markets to FSC. The company also has noticed a trend toward premium products, those made from stainless steel and outfitted with high-grade fabrics, and other options.

“We ship 1,000 seats each day,” Bar-Sheshet said. “The average frame requires 110 in. of tubing, so that’s about 9,000 feet per day.” The shop runs like clockwork, moving all these finished products through nine shipping docks each day using several freight companies. It’s a lot of activity, but the company isn’t locked into huge product runs and inflexible schedules. It’s nimble and versatile.

“We can ship an order seven days after we receive it,” he said.

About the Author
FMA Communications Inc.

Eric Lundin

2135 Point Blvd

Elgin, IL 60123

815-227-8262

Eric Lundin worked on The Tube & Pipe Journal from 2000 to 2022.