The Surgeon & the Gear Maker

OD Grinding of Cylindrical End of Gear Blank

Delta Gear bought TIFCO Gage & Gear, a maker of master gears, spline gages, aerospace gears, and automotive prototype gears since 1964, 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 people.

Delta Research
Officials started Delta Research 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.

The company has done transmission components for Chrysler, and back in the 1990s, engineers there designed many of the dual clutch transmissions. The company would prototype the Chrysler designs start to finish. Most jobs are small run, pre-production launches. After that, the job goes off to a production supplier. The key at Delta Research is workers’ knowledge in design for manufacturing (DFM) and manufacturing feasibility. They help engineers define the right way to design a part to make it manufacturable for production.

The company also does gears as well as 3-, 4- and 5-axis machining of housings from castings, forgings, or from solid. It also does cylindrical grinding, honing, and other applications. The breadth of what occurs at Delta Research is a lot wider than goes on 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. Completion of the three prototype transmissions, from design to build, was in 26 weeks, which is a quick undertaking.

“The industries each company addresses are entirely different,” says Tony Werschky, partner,Delta. “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 is 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.”
 

This panoramic view of the Delta Gear facility shows the line of Studers on left side, while center and right are KAPP and Höfler gear cutting and hobbing machines.

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,” Werschky says. “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.”

Delta Gear (aka TIFCO Gage & Gear) has had an impressive history of making some very difficult gears. One of the company’s manufacturing highlights in the 1980s was making a wrench that would work in zero gravity, which NASA used in modifying the Hubble Space Telescope. Today Delta continues work with NASA, as well as many of the OEMs in the aerospace industry.

Recently Delta Gear purchased a local newspaper’s old, forgotten building and turned it into a state-of-the-art, 72,000ft² 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. Aside from heating the surgeon and gear maker treatment specialty coatings, all of the rough cutting of the gears, turning, any special milling in the part finishing process after case hardening, and working the journals and faces is in-house.

Grinding Gear Blank Between Centers

“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,” Werschky notes. “The 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 is more opportunity for failure, which limits the amount of competition that can make that part. There is more risk involved, of course. It is kind of like the surgeon who gets all tough procedures because he is the best. High risk, high reward. If you are good, then you do well. If you are the very best, then you do very well.”

Delta Gear weathered the turbulent economy of 2008 and 2009 really quite well. Some of the weaker companies folded during this time and Delta Gear benefited by taking over some of its competitors’ jobs, as unfortunate as that might be. The company bought several machines in 2008 and 2009 because the deals were too good to pass up. For example, it bought the S40 in 2009 along with the German KAPP VUS 50 CNC gear grinder. In 2008, it also bought gear grinding, gear cutting, and 5-axis CNC machines.

“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 are 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,” Werschky says.

The amount of precision on the gears that Delta makes limits the number of companies that can do what Delta does, so Werschky is not worried about underbidding. More than likely, a foreign competitor cannot do what Delta does, and if they can, they probably have the same machines and the same type of costs that Delta has, so Delta would be competing closely with them. However, Delta rarely finds itself in that position.

“What I am starting to see more and more 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.”, Werschky says. “Most of what we make stays in the U.S. We really have not 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 come to us from 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,” Werschky says. “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 is just very impressive – so clean you could eat off the proverbial floor – which is not 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. Lined up, one right beside the other and all looking brand-new, it is hard to believe that some may be 5 years old and older. Studer has an excellent reputation in the industry, and people who know grinding understand this very well.

Operator Programming the Studer S40

“The Studers that we have range throughout the last two decades, and the older Studers still hold the tolerancing and produce the results that we are looking for. In addition, what we are 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,” Werschky explains.

“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 is why we prefer to buy their products.

“We have an S20 CNC and an S21. These can handle parts up to 10.0" in diameter,” Werschky continues. “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 16.0" to 40.0".

“The S40, our newest Studer, was purchased on 2009 and has opened some doors to new clients due to its versatility,” Werschky says. “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 is 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 could not compete in the past because we did not have the capability. We are 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 is so much thread grinding in aerospace. Now we do all of that in-house. It can also do spline grinding as well, but we do not really use it due to our wide assortment of dedicated gear and spline grinding machines. The turret wheelhead can be swiveled automatically and up to four grinding wheels used. The S40 also has a high-resolution B-axis.”

Working in Tight
“We consider ourselves the leader in precision grinding technologies,” Werschky says. “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.”

Scott Sakuta, Partner, Delta, left, and Tony Werschky, Partner, Delta, stand before the Studer S40.

When tolerances are so tight, and the expectations of aerospace customers are so demanding, one cannot 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 2µ". The Studers can grind down to a 4µ". A light polish afterward gets the surface down to under 2µ". Therefore, 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 so these parts are very hard, and they require tight-tolerance cylindrical grinding,” Werschky adds. “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 60Rc, some over 70Rc. 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 60Rc, and it also aids in surface finish control,” Werschky explains. “Further, we do considerable shaft grinding in both automotive and aerospace. In automotive, it is 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 will go down to 0.500" in diameter depending upon which shaft we are talking. 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 is a longer part, you are looking at 0.002" concentricity over 24". In aerospace, 0.002" over 10". Typically there are three different diameters per shaft.”

First, Take Care of the Parts
Werschky says it is very hard to find the right people you need in this business. You cannot just take a guy off street and have him run a million-dollar machine on the floor. Delta has an internal training program where some of the younger employees who are working in different aspect of the company are put through a training regimen. This teaches them how to take care of the parts and appreciate the parts, because if damaged parts are no good to Delta or to a customer.

The next thing they learn is to take care of the machines because if the machines do not work the company cannot make parts. There is a level of respect that Delta teaches these employees in order for them to come in, act professionally, and respect the parts and machinery. From there, Delta teaches them how to inspect the parts, using micrometers and the different gages, so that they know what they are looking at when they are 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, CMMs, and optical gear checking equipment, roundness testers and surface profilameters and much more. So there is a whale of inspection to learn,” Werschky says.

From there, Delta teaches them how to run the machines.

ABOVE:  Studer S33 Set up for Grinding Between Centers. BOTTOM: ID Grinding of Gear Blank.

“This program takes a couple of years,” Werschky says. “These guys start out in hobbing or gear cutting. They will cut gears first, and then 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 employees, see where they are flourishing and where they are not. By the end of the program, we know where they are going to fit and we move them into that department to help it expand. Therefore, we do significant internal growth of our people. You cannot 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, it has significantly grown its OEM business during the past three years due to their AS9100 certification. To approach a new OEM today, a business needs to be AS9100 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 is what AS9100 helps guarantee.

“This did not 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 are 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 cannot have that on flight critical aerospace parts that are going to be moving a plane through the air.”

United Grinding Technologies
Miamisburg, OH
www.grinding.com

Delta Gear
Livonia, MI
www.delta-gear.com