Tendon Manufacturing ramps up air purifier production

As demand for its air purification units ramped up throughout 2020, the fabricator expanded its electromechanical assembly operations. Images provided by Tendon Manufacturing

Anyone who’s worked in custom metal fabrication probably knows all about the drop-in order. The customer’s implicit message: We need this yesterday.

Those at Tendon Manufacturing, a custom sheet metal and machining operation in Warrensville Heights, Ohio, are drop-in-order veterans, considering their experience in retail displays. When major retailers call, they usually need their displays as soon as possible.

“Especially over the past five years, we’ve built ourselves up to have this kind of adaptability.”

So said Michael Gordon Jr., the sales manager at Tendon who has been working with operations and purchasing on what has become an unprecedented project for the company: fabrication and assembly of commercial air purifiers, a market that, thanks to the pandemic, has increased dramatically over the past 12 months.

For custom fab shop managers who keep a keen eye on revenue concentration and diversity, Tendon’s ramp-up might raise a few eyebrows. On the surface, it sounds as if Tendon just shifted focus from one up-and-down market to another: retail displays to the pandemic-induced demand for air purification. But Tendon doesn’t put all its eggs in one market basket.

“Right now no one customer makes up more than 10% of our business,” Gordon said. “And if we break it down by market section, there’s not one market that makes up more than 20%.”

That’s easier said than done, so how does Tendon maintain such a diverse revenue mix? It has to do with something that was developed partially in reaction to those drop-in orders: adaptability. Still, there’s more to it than shop floor improvements.

Think of Tendon’s adaptability as a stool with three legs: One represents best shop practices; another is training; and the third is supply chain collaboration, including a supply chain strategy that has built a network of reliable component suppliers and subcontractors.

Some History

Although the fabricator does play in the medical manufacturing sector, Tendon Manufacturing has nothing to do with tendons. The company name is a combination of the founders’ last names: Greg Tench and Michael Gordon Sr. The company launched in 1988 as a six-employee machine shop, and soon after the founders added sheet metal fabrication. Over the years the company expanded its product mix to include architectural work, medical, lighting, and, of course, point-of-purchase displays.

About five years ago a customer approached Tendon to make the sheet metal components for a unique kind of air purifier. Designed for nursing homes, hospitals, dentist offices, and other interior spaces with a need for extremely clean air, the purifiers have two filters. The first filters larger particles. At this point the partially cleaned air is hit by a UV light source designed to kill airborne pathogens. From there the air passes through a second filter.

In recent years Tendon Manufacturing has replaced its CO₂ lasers with four 4-kW fiber lasers.

In 2016 the product was just one of the numerous other small jobs Tendon produced, part of the “long tail” of the shop’s product mix. “Since 2016 we made between 400 and 500 of these filters in total,” Gordon said, “up until 2020.”

Like many fab shops, Tendon’s 2020 began like a roller coaster. “2020 for us started out very strong, mainly because of our point-of-purchase display business,” Gordon said. “Our retail customers usually do big rollouts during the first quarter. But once we started seeing the effects of COVID-19, sales bookings began dropping around 30%.”

Then by April, demand for air purifiers began ramping up. And within a few weeks, demand had risen so much that the entire nature of the job changed. In the beginning of 2020 Tendon was shipping between 10 and 20 purifiers a month. By December it was shipping 700 to 900 a week.

Thanks to COVID, demand for these air purifiers is coming not just from hospitals and medical and dentist offices, but also from a variety of places where people congregate, including schools. Continually wiping down surfaces can help only so much if the virus floats freely through poorly circulated, unfiltered air.

“Before the pandemic, most schools had little if any air filtration,” Gordon said. “No one had thought about the need.” Increasing the airflow and filtering the air can prevent pathogens from spreading, “and that’s what these filters can do.” He added that air filters don’t prevent the spread of all airborne pathogens, of course, but having a well-designed airflow and filtration system is certainly better than having nothing at all.

Purchasing and Manufacturability

For the first time in its history, Tendon found itself ordering certain electronics parts by the containerload—a result of an effort to ensure assemblers had the mechanical and electrical components they needed. The fabricator tries to maintain at least a two-week supply of purchased components inventory. For some items where lead times continued to grow—often to more than 12 weeks—purchasers identified potential “crosses,” substituting parts with those having shorter or more predictable lead times and working with the customer to test them.

“We then started realizing that, for some of these items, we were using up a lot of everyone’s U.S. supply, so we started to make friends overseas,” Gordon said. “That’s when we started having certain electronics components shipped directly to us by the containerload.”

Company engineers also worked with the customer on sheet metal design for manufacturability. Did materials really need to be different thicknesses or grades? Identical thickness and grade could help nesting on the laser and simplify setups on the press brakes. Did hole patterns need to be a certain way, or could they be adjusted to optimize laser cutting time?

Tendon managers scrutinized the order-release-to-ship cycle. Could any process be simplified or eliminated? Welding was an obvious target. Before the ramp-up, the air purifier’s enclosure had manually welded gas tungsten arc welded (GTAW) joints that also had to be ground down manually. Where managers could, they worked with the customer to replace certain welded joints with riveting. They then replaced the remaining GTAW joints with a robotic gas metal arc welding process that, thanks to its limited heat input and precise arc control, required no postweld grinding whatsoever.

Flow and the Supply Chain

Machine technology has allowed companies like Tendon to ramp up fabrication capacity to unprecedented levels without hiring a significant number of employees. Tendon installed its first fiber laser four years ago; that one machine replaced three older CO₂ lasers. Now Tendon has four 4-kW Baykal fiber laser systems.

Because so many parts flow quickly from cutting to the rest of the plant, managers needed a better way to keep track of it all. So in recent years the company implemented a color-coded work flow system. Color-coded job travelers and identically colored metal labels sit with every job on every cart holding work-in-process. The schedule tells employees where each color in the shop should be. If a cart with certain colors is in the wrong place, it’s immediately apparent to everyone.

Those four fiber lasers feed seven press brakes. To absorb the increased cutting capacity, the press brake department now operates over first and second shifts, along with a few operators on third shift to handle the overflow.

Managers made similar considerations for powder coating. At this writing, the coating line paints air purifiers exclusively on first shift while painting everything else during the second and third shifts. And throughout all shifts, operators have developed part-hanging strategies to increase part density on the line wherever they can.

Tendon is also in the middle of an expansion. A newly purchased building next door is 50,000 sq. ft., effectively doubling the fabricator’s manufacturing space. It’s the future home of the company’s machining and assembly operations. Tendon also will soon be installing a new powder coating line and adding yet another fiber laser.

Before 2020 Tendon sent air purifiers to the distributor, which installed the filters and final components before shipping them to customers. With order volumes now so much greater, however, final assembly shifted to Tendon.

Considering all this, you might think Tendon would be hiring assemblers left and right, and the company is to some degree. But managers also know how risky it is to hire employees just to handle a large job from a single customer.

To mitigate that risk, Tendon subcontracts certain subassemblies for the air purifiers to other companies, including OEMs within Tendon’s current customer base. “We’ve subbed work out to a lot of our OEM customers that happened to be slow [in 2020],” Gordon said. “It was nice to be able to give back to some of our customers. We were able to give them business, as opposed to vice versa.”

That said, Tendon is still hiring in a big way; it’s just that, without its subcontracting strategy, it would have hired a lot more. At the beginning of 2020 it had 65 employees; six months later it employed about 100 people; and in 2021 it’s planning to hire about 25 more.

Training Strategy

Doubling the employee head count in just six months would be challenging for any company, but Tendon also must deal with the same challenge fabricators across the industry face: the lack of experienced talent.

In general, the shop’s new hires who have experience comprise a broad group. Some do have experience specific to metal fabrication. “If an experienced press brake operator walks in the door, we don’t care if we’re in a recession, we’re going to hire that person,” Gordon said. “Those people are few and far between nowadays.”

Of the 35 Tendon hired in 2020, about 10 were skilled people with relevant experience—not a bad amount, considering the industry’s broader hiring challenges. Of course, even if an employee has relevant machine experience doesn’t mean he or she can jump in and perform a complicated setup. Newly hired “experienced operators” can be anything from button-pushers (that is, someone else set up and programmed the machine) to technical gurus (though, of course, the guru is the rarest new hire of all).

The remaining new hires either had experience in assembly or other industrial sectors, while others were entirely new to manufacturing. “We had to spend time with these people,” Gordon said, “teaching them to read blueprints and shop routers.”

Training depends on a new hire’s experience, but during a period of rapidly rising demand, the nature of that training changes. Gordon called it “training on the go. We put them where we need them right now. We first get a sense of where they worked and what they’re comfortable with.”

This is where classifying the experienced comes into play. Fully experienced people can help in a range of areas; button-pushers can do various tasks, but not certain machine setups; those with assembly experience help in assembly, perhaps become trained in more sophisticated levels of electrical assembly; total novices might help retrieve material or work in packaging and shipping.

“We try our best not to fit a square peg into a round hole,” Gordon said. “It’s about where he or she fits in.”

Like many fabricators, Tendon also has a new-hire buddy system, especially for machine operation. Beyond the typical first-article inspection, over their first month new operators have parts checked and signed off by experienced personnel at frequent intervals, such as every 10th part. Modern machines are extraordinarily productive, which means in short order they can produce an extraordinary amount of good or, if set up or run incorrectly, bad parts. And for the typical high-product-mix fabricator, rework is the worst kind of waste: An operation pays to make it, pays to make it again, and pays the opportunity cost as the money-losing rework steals available capacity that could have been sold.

No wonder fabricators cite hiring and skilled labor as some of the most challenging aspects of running a company. As Tendon’s story shows, the trick is to hire only when demand is sustainable, considering all the work that goes into bringing a new hire up to speed. Meanwhile, that network of subcontractors can carry the fabricator through those dramatic, yet unsustainable, peaks in demand.

Growth Ahead

Gordon said that Tendon plans to continue hiring and buying equipment this year. In fact, the company could end 2021 with double-digit growth—and for several reasons. First, the air purification product isn’t like other pandemic-related products with flashes of intense demand followed by nothing. People need hospital beds only when they visit the hospital. But people want themselves and (especially) their children to breathe clean air. Demand from school districts and other institutions might not drop off a cliff when more of the population becomes vaccinated.

Second, even as demand peaked in November 2020, air purification work never surpassed 10% of Tendon’s overall revenue. The fabricator’s revenue remained diverse throughout last year.

Third, the forecast and backlog look bright. “We’re already on pace to be booked for the rest of May,” Gordon said. “So our first and even the beginning of our second quarter are looking very good.”

In this way, Tendon’s outlook reflects that of many custom fabricators across the U.S. After a year we’d all like to forget, 2021, for Tendon and others, might well be a year to remember.