The Surgeon and the Gear Maker

The very best surgeons perform the most difficult procedures—those requiring extreme skill, precision, deftness and experience. The same is true of the very best gear makers—they gravitate toward the most difficult jobs—those requiring the very best technology, extreme skill, precision and experience.

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Delta Gear bought TIFCO Gage & Gear, a maker of master gears, spline gages, aerospace gears, and automotive prototype gears in 2004. In 2005, Delta Gear joined forces with Delta Research Corp., which since its inception more than a half-century ago has earned a reputation as the leader in prototype transmission and engine components and assemblies. Together the two employ more than 110.

Delta Research
Delta Research started in 1952 as a supplier of prototype transmission and engine components for the Big Three automotive companies, and they continued to expand on that front. Then they went into aerospace work, designing engine test stands and other types of components for aerospace and defense. Figure 1

The company has done transmission components for Chrysler, and back in the 1990s they designed many of their dual clutch transmissions. They would prototype the Chrysler designs start to finish; most jobs are small run, pre-production launches. After that the job then gets handed off to a production supplier.

The key at Delta Research is their knowledge in design for manufacturing (DFM) and manufacturing feasibility. They help engineers define the right way to design a part to make it ready for manufacturing production.

The company also does gears as well as 3-, 4- and 5-axis machining of housings from castings, forgings or from solid. They also do cylindrical grinding, honing and other applications. The breadth of what‘ being done in Delta Research is a lot wider than what’s being done at Delta Gear, where the focus is almost entirely on aerospace gears and shafts.

Last year Delta Research undertook a unique assignment: three completely new design transmissions for the tractor-trailer industry. These were complete transmissions for 18 wheel, big heavy-duty trucks and long-haul tractor-trailers. The three prototype transmissions were completed, from design to build, in 26 weeks, which is a pretty quick undertaking. Figure 2

"The industries each company addresses are entirely different," says Tony Werschky, Delta partner, "and we are set up this way, between automotive, aerospace and defense, so that our businesses maintain a certain amount of stability regardless of market conditions. At Delta Research it’s pretty much automotive, truck, and defense work, while Delta Gear is nearly all aerospace, jet engines and rocket components. When we bought TIFCO Gage & Gear in 2004, it was a small shop, just a fraction of what we see today at 12 employees. Now, there are nearly 50 employees at that particular location alone."

Delta Gear
"Bob Sakuta, my father-in-law, and son of the initial owner, Alex, came to work here in 1976 and has been here ever since," says Werschky. "He was running machines out on the floor back then. Now he oversees the companies and manages the growth strategies, while Scott Sakuta and I do more of the tactics." Figure 3

Delta Gear (aka TIFCO Gage & Gear) was started in 1964 and has had an impressive history of making some very difficult gears. At one point, they made a wrench for NASA that would work in zero gravity.  It was used to modify the Hubble Space Telescope. That was a highlight during the 1980s for TIFCO. And today Delta does a lot of different components for NASA as well as many of the OEMs in the aerospace industry.

Recently Delta Gear purchased the local newspaper’s old, forgotten building and turned it into a state-of-the-art, 72,000-ft.2 facility completely devoted to gear production, gear inspection and metrology. Many of the materials ground are exotic, including super hardened materials that are very difficult to machine. They do all the work on gears and shafts in-house, other than heat treatment and specialty coatings. All of the rough cutting of the gears, such as turning, any special milling in the part finishing process after case hardening, where they are cutting gear teeth and working the journals and faces is done in-house.

"It depends on the complexity of the part, but we may send a part out a number of times for selective heat treating of certain features and plating," notes Werschky. "On typical gear, we turn it, rough it, send it out for heat treatment and then finish it. Some parts, however, require more than just heat-treating. They may require copper plating or silver plating at different times, and that makes for a longer process or progression from start to finish. We really like the more difficult jobs because there’s more opportunity for failure, which limits the amount of competition that can make that part. There is more risk involved, of course. It’s kind of like the surgeon who gets all really tough procedures because he’s the best ­— high risk, high reward — if you’re good, then you do well.  If you’re the very best, then you do very well." Figure 4

Delta Gear weathered the turbulent economy of 2008 and 2009 quite well. Some of the weaker companies folded during this time, and Delta Gear benefited by taking over some of the jobs of their competitors, as unfortunate as that might be. They bought several machines in 2008 and 2009 because the deals were too good to pass up. For example, the S40 was purchased in 2009 along with the German KAPP VUS 50 CNC gear grinder. Additional gear grinding, gear cutting and five-axis CNC machines were bought in 2008 for Delta Research as well.

"Our growth for Delta Gear will be in expanding our relationships with OEMs in the industry on precision gears in jet engines and other aircraft components. There has been considerable outsourcing of OEM components recently, which has benefited us in our growth. The way Delta Gear is positioned right now we’re in a good place to handle more growth. So we feel we can handle a significant amount of expansion with the OEMs in the aerospace industry," says Werschky. Figure 5

The amount of precision on the gears that Delta makes limits the number of companies that can do what Delta does, so Werschky’s not worried about being underbid by a foreign competitor. More than likely they’re not going to be able to do what Delta does, and if they can, they probably have the same machines and the same type of costs that Delta has, so in this case Delta would be competing pretty closely with them. However, Delta rarely finds itself in that position.

"What I’m starting to see more and more," says Werschky, "is that Chinese aircraft are made in China for Chinese customers, European aircraft are made in Europe for European customers, and the same applies in the U.S. Most of what we make stays in the U.S. We really haven’t gone after the European market yet because we see a significant amount of growth opportunity in the United States. We view the market cautiously because if we were to take on too many new customers it could actually prove detrimental to the company. We have a balancing act in keeping the right amount of engineering staff on hand for parts that are being given to us by our customers. For the size of our company, bringing in a new major OEM every year or two is a very good way to continue our growth organically."

A Studer Showroom
"Our facility looks like a showroom for Studer," says Werschky. "There is a stable of six Studers (United Grinding Technologies, Miamisburg, OH) in a new facility. Although the plant is generally closed to outsiders, we do give tours on occasion. Our customers are welcome in our shop, and when they see the facility, their first impression is, ‘Wow.’ It’s just very impressive — so clean you could eat off the proverbial floor — which isn’t the norm in most gear manufacturing companies, certainly not those of the past, which tended to be oily, smelly and slippery under foot. Our facility is ultra-clean, bright and orderly. Seeing the Studers is also impressive. They’re lined up, one right beside the other, and they all look brand-new even though one or two may be five years old and older. Studer has an excellent reputation in the industry, and people who know grinding understand this very well.

 "The Studers that we have range over the last two decades, and the older Studers still hold the tolerancing and produce the results that we are looking for. And what we’re looking for is very high precision, tightly toleranced parts with a superior surface finish. We have very difficult-to-machine materials that are exceptionally hard after their final heat treatment, so we use special grinding techniques to finish these parts, and United Grinding is very helpful in interacting with us and helping us to maximize our efficiencies and the output of the machines and getting the right results consistently. Figure 6

"The reason we buy Studers is because Studer continues to push the envelope on leading edge technology, from the way their Granitan® machine beds are designed to the technology in their drive systems. We recognize that they continue to push the envelope and refine their products and that’s why we prefer to buy their products.

"We have an S20 CNC and an S21. These can handle parts up to 10" in diameter," continues Werschky. "The S33 and the S31 go up to 13.8" and the S40 goes up to 17.7" in diameter. Their center distances range from 16" to 40". Figure 7

"The S40, our newest Studer, was purchased in 2009 and has opened some doors to new clients due to its versatility," says Werschky.  "It has a Y-axis that allows us to install an ID spindle in a vertical orientation so that we can grind slots and keyways. It’s very important for grinding our most complex parts.  It also has C-axis for out-of-round grinding. This is essential for grinding cams and lobes; applications in which we really couldn’t compete in the past because we didn’t have the capability. We are one able to grind these down to within 0.0002" of a degree. The C-axis also provides thread grinding. We used to outsource that application because there’s so much thread grinding in aerospace. Now we do all of that in-house. It can also do spline grinding as well, but we don’t really use it due to our wide assortment of dedicated gear and spline grinding machines. The turret wheel head can be swiveled automatically and up to four grinding wheels can be used. The S40 also has a high-resolution B-axis."

Working in Tight
"We consider ourselves the leader in precision grinding technologies," says Werschky. "We are not the largest, nor are we the smallest. We are a precision gear facility and not only are our precision gears important, but the journals and faces that ride next to them are in many ways just as important if not more important. We buy the best machines for the applications that we do, and we tend to gravitate toward the more difficult applications, and having the right equipment and the right tools, it becomes obvious why we are sought out for those kinds of jobs." Figure 8

When tolerances are so tight, and the expectations of aerospace customers are so demanding, one can’t afford to take chances or cut corners on diameters that have to be 50 millionths in roundness. Some parts that Delta Gear produces require a super finish to less than two micro inches. The Studers are capable of grinding down to a four micro inch. A light polish afterward gets the surface down to under two micro inches. So the Studers really help Delta optimize its processes to eliminate time and more rapidly get parts to their destination.

"The master gears that we make are made out of tool steel," Werschky adds, "so these parts are very hard, and they require tight-tolerance cylindrical grinding. When you have diameters that have to be held very tightly, the Studer is exemplary in its ability to meet and to exceed the requirements and our expectations. For example, 20 millionths in roundness, 50 millionths in flatness and 0.0001" or 0.0002" typical run out.

"The materials we grind are nearly all exotics with a hardness of over 60 Rc, some over 70 Rc. These are very brittle and susceptible to burning and cracking, so we need machines that are not only capable and reliable but also extremely accurate and repeatable. Studer delivers what we need to handle these materials. We use rotary diamond dressing tools, allowing us to use different grinding wheels. This helps us with hardened materials, over 60 Rc, and it also aids in surface finish control. Further, we do considerable shaft grinding in both automotive and aerospace. In automotive, it’s common for these shafts to have multiple diameters. The Studers are very capable of handling multiple diameters in one operation.  We do a shaft where the largest diameter might be 6", but most are 3" to 4" in diameter. In aerospace, they’ll go down to 0.500" in diameter depending upon which shaft we’re talking about. In automotive shafts, the concentricity might be 0.001" to 0.002", and in aerospace it might be one-quarter to one-half of that, depending on the length. If it’s a longer part, you’re looking at 0.002" concentricity over 24 in aerospace, 0.002" over 10 inches. Typically there are three different diameters per shaft." Figure 9

First, Take Care of the Parts
Werschky says it’s very hard to find the right people you need in this business. You can’t just take a guy off street and have him run a million-dollar machine on the floor. Delta has an internal training program where they take some of the younger guys who are working in different aspects of the company, and they put them through a training regiment that teaches them how to, first of all, take care of the parts, to appreciate the parts because if you damage the parts they’re no good to Delta or to a customer. So the first thing always is to take care of the parts.

The next thing is to take care of the machines because if the machines don’t work you can’t make parts. There’s a level of respect that Delta teaches these employees, so that they come in and act professionally, and they respect the parts and machinery.

From there Delta teaches them how to inspect the parts, teaches them how to use micrometers and the different gauges and such, so that they know what they’re looking at when they’re making a part. "I think we have more gear inspection equipment here than any other private company our size in the world. We have nine gear checking machines, CMM’s and optical gear checking equipment, roundness testers and surface profilameters and much more.  So they are a whale of inspection to learn," says Werschky. From there, Delta teaches them how to run the machines. Figure 10

"This program takes a couple of years," says Werschky. "These guys start out in hobbing or gear cutting. They will cut gears first, and then they’ll move over to another department, maybe do some inspection for a while to learn how to inspect parts properly, and then they will move over to grinding. As we go through this process management talks with the leaders of those departments to check on the progress of these guys, see where they’re flourishing and where they are not. By the end of the program we know where they’re going to fit and we move them into that department to help it expand. So we do significant internal growth of our people. You can’t just send them to gear school and have them come back a week later with everything they need to know about making gears. We make a considerable investment in our employees which is a necessity if you are looking to grow over the long-term."

Still New at the Game
Delta has been servicing the OEM market for decades; however, they have significantly grown their OEM business over the past three years due to their AS9100 certification. If you want to approach a new OEM in today’s day and age, you have to be AS 9100 certified. Because OEMs want to make sure you have the controls, systems and processes in place to ensure you make the part consistently, right every time. That’s what AS 9100 helps guarantee.

"This didn’t take us long," Werschky says. "We were already compliant. We just had to spend the money and have the auditors come in and see what we were doing to confirm that we were compliant. We’re also NADCAP certified for nondestructive testing, magnetic particle inspection which checks for cracks, as well as nital/temper etching, which is like an acid bath where you check for grinding burns. Those processes are done in-house, under our control, because whenever you grind a part, there is an opportunity that you might crack the material or burn the material, and you can’t have that on flight critical aerospace parts that are going to be moving a plane through the air." 

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is the founder and editorial director of RYB Communications, Hebron, KY. He has been writing about manufacturing for more than 35 years.