Custom Gears Often Require Custom Lead Times

Jack McGuinn, Senior Editor

Makers of custom gears are a breed apart from other gear manufacturers. That’s because, among other distinctions, the sophistication level of machinery capability (and capital investment), expertise and process management required to be successful in custom gear manufacture is in another stratosphere in comparison to makers of stock, commodity-type gears.

Of equal importance in the custom gear universe is lead time—so much so that it can make the difference in whether or not an order is secured.

But what, exactly, is a “custom gear”? The question elicits a variety of responses.

“Any gear that is specifically designed for a particular application (not a catalog item) can be called a custom gear,” says N.K. “Chinn” Chinnusamy, president of Excel Gear Inc. of Roscoe, IL. “The so-called custom gear may have special bore or face configuration or sometimes special pressure angle or DP (diametral pitch) or module.”

“A custom gear is simply a gear that is not commercially available and that is designed to specifically meet a defined set of customer specifications,” says Kika Young, HR director at Forest City Gear, also in Roscoe.

“Built to suit customer’s specific requirements,” says Jim Mantei, vice president of business development and operations for Vancouver Gear.

“A custom part or gear is engineered, designed and manufactured to meet specific performance and envelope requirements that are not available with an existing product,” says Abby Dress, of Smith & Dress Ltd., speaking for Precipart in Farmingdale, NY.

“Gears that are manufactured in small quantities (1-25), in accordance with a specific drawing provided by the customer or as designed for a specific application,” says Tom Ryan, general manager, industrial components group, for Cincinnati-based Xtek.

Arrow Gear Company (Downers Grove, IL) president Joe Arvin puts it this way: "In general, custom gears can best be defined as gears manufactured from customer's specific application or designed by the gear supplier to meet a specific application for their customer."

And last, “For HMC, custom is a request for components that we have not made in the past or for which a customer does not have specific manufacturing parameters or drawings to provide, says John Schnarr, sales manager for the Princeton, Indiana-based company. “In other situations a customer may ask for design alternatives or product improvements and those changes I suppose by definition would be custom.”

Returning to the lead time issue, manufacturing time depends on the shop—i.e., their capabilities and what is promised to the buyer. Some shops are involved almost from inception—design, prototyping, etc. For others—not so much. Let’s look at design involvement, for example.

“At Forest City Gear, we do no in-house design and are not design responsible, says Young. “We will, however, suggest revisions regarding tooth specs or material should we see (that it’s) necessary or advantageous.”

Says Vancouver’s Mantei, “We are a manufacturing company and we work with our customer providing support to assure the final design meets our customer’s requirements.”

“Yes, most of the time, we do get involved,” says Excel’s Chinnusamy. “In special cases, our customer may require design help. We were offered the contract for design and analysis of Navy battleship gun turret gear boxes. The first phase of the project was design and analysis only.”

“Unless the customer has completed a thorough evaluation of the design and manufacturing processes required, the gear manufacturer should be involved in the customization process,” says Press. “This ensures that it incorporates the performance and envelope requirements that are part of the customer’s needs.”

“We participate from the standpoint that we develop gearboxes for specific applications or reverse gearing from an existing application,” says Xtek’s Ryan. “We often provide rating analysis and gear design upgrades as part of working with our customer.”

"When we make gears to the customer's specifications, the customer has sole responsibility," says Arvin. "Typically, the customer performs the full load testing and if the tooth contact does not meet his expectations, Arrow will make redevelopment modifications to the gears supplied. Once the customer completes the full load testing, and if it meets their requirements, the responsibility lies with them. Arrow Gear is responsible for the workmanship of the gears supplied.

"However, Arrow Gear is unique insomuch as we often perform engineering gear designs to meet the customer's specific requirements (such as RPM, torque, deflections and life-cycle) to achieve the desired results. We have been extremely successful in predicting the exact location of the contact bearing pattern on bevel gears when placed under full load, thus eliminating the costly redevelopment time."

“We work with the customer on design requirements and ultimately an approval on the final design of the components,” says HMC’s Schnarr. “It’s the customer’s responsibility (with our assistance), to decide on what he wants as a final product and to provide specifics on the application and loading dynamics of the components. It is then up to us to come up with a total design concept to meet those requirements.”

If design and the usual attendant R&D are involved, that will obviously impact upon lead time. In such scenarios, how completion due dates are arrived at differs from company to company.

“If we are involved in design and R&D, it will have its own lead time,” says Chinn. “Sometimes, the customer wants us to design and then pays us for the design service. Then, they may send the drawings to several companies for bids on manufacturing, and that was the case with the recent Navy gear box project. (We won the project, by the way!)”

“It depends,” says Mantei. “Sometimes customers contact us in advance and we work out the details before an order is placed. Other times, a sample is sent in and the clock starts running. Design and quick delivery are required.”

“It is not realistic to exclude any part of the process—fabrication or intellectual efforts—from the lead time,” says Dress. “Initially, the first time a gear is made, it is a start-up process. The design, fabrication, material sizes, availability, outside processes and internal scheduling must be reviewed at the outset. There is a subtle impact on lead time even for very small and simple variations. A responsible company often sets the lead time to reflect some level of safety so the customer is not disappointed.

“With subsequent orders, the conceptual and planning time is eliminated, since these are now known quantities. A level of maturity, experience and skill have been built into this new product so that the time is more predictable.”

"In all cases, the design and R&D are incorporated into the lead time," says Arvin.

“When a new design is being provided—e.g., a custom-designed gearbox—the time for the engineering work is included in our project lead time,” says Xtek’s Ryan.

“Generally, discovery time or R&D is on the front end before we begin a project,” says Schnarr.

Aside from unrealistic customer expectations, probably the key potential unknown in lead time assessment is material availability. In today’s world economy, material source and supply can be a major impediment to meeting time expectations. Too, it depends on the specified material. Specialty steels, for instance, may be in short supply. But it’s all part of the mix in custom gear manufacture.

“If special material is involved, then that will impact the lead time. Otherwise, lead time will not be affected if price is not a concern. We can usually get material if we are prepared to pay premium prices,” says Chinnusamy.

“Material availability directly affects lead times, says FCG’s Young. “We do not stock most materials for blanks, and even if we are performing cut-teeth-only processes, it is still important for the customer to procure such materials. Furthermore, it is not uncommon for custom gears to require exotic materials, which can have even longer lead times.”

“We stock most common carbon steel alloys for parts under 18" diameter,” says Mantei at Vancouver. “Castings and forgings can take a number of weeks, but we keep strategic material (in) stock for repeat customers”

In a word—“Considerably,” says Dress. “In this global economy, materials acquisition control is difficult. Size figures into the availability equation, too. A larger stock size may have to be purchased as a substitute for a hard-to-find desired size, but its purchase means the product may be more expensive and require added machining time. This option may be unavoidable in order to meet a demanding lead time.”

“For smaller-size parts that are manufactured from bar stock (under 24"), material typically does not impact lead time,” says Ryan. “However, when special forgings are required, the lead time of the material must be considered in the overall delivery of the component.”

Says HMC’s Schnarr, “When you are talking custom products of the scale we normally produce, (material) has a huge impact. If you are looking for large casting or custom-forged rings and shafts, the lead times can be significant and commonly be more than half of the delivery time.”

And then, of course, additional steps are involved in the custom gear process. You might say that is what makes them custom. And you’d be correct. Prototyping, enhanced inspection and other quality assurance measures are often part of the job, again recognizing that much of this depends upon a gear company’s capabilities and business plan, as the following responses indicate.

“We conduct first piece inspection after all machining operations,” says Xtek’s Ryan regarding the extra steps involved in orders requiring prototyping, etc. “We have several in-process inspections of all pieces before and after heat treat. Lastly, we conduct a 100 percent final inspection of ‘customer critical dimensions’ on all parts before shipment.”

At Precipart, “Whatever the customization, there are always extra steps,” says Dress. “The manufacturer must deal with non-standard shapes, special tooling and meeting specifications on a drawing, etc. These steps depend on the overall complexity. Prototyping is required to confirm the customer’s expectations. It often is required or recommended for any new program to assure that the parts will meet the expectations of the requirements, work through the production process and qualify the part for production.”

“More design time for initial order, on all orders—prototype or repeat—we perform 100 percent inspection,” says Vancouver’s Mantei.

“Although Forest City Gear does not provide design work, there are some extra steps in custom gears beyond the design process,” says Young. “Generally there is prototype creation for testing and perhaps modification later on. Inspection and quality control, especially for first time orders, are always maintained at higher levels.”

But at Xtek—showing it depends not only on the shop, but also the markets it serves—“We do not prototype for the markets we currently serve,” says Ryan.

“Prototyping, adding several in-process inspections, strict quality control and meetings with suppliers to discuss the difficulties and expected quality requirements of outsourced operations such as heat treating etc.,” are all fair game, says Excel’s Chinnusamy.

And at Arrow Gear, "Material availability has a direct impact on lead time. Bar stock can be obtained in a couple of weeks," says Arvin. "But forging availability can take from 12-26 weeks."

“Generally we do not prototype gears,” says Schnarr. “We do have to be very careful on setting up the proper processing sequence and as always when doing something for the first time, extra care must be taken to insure proper set-up and inspection processes.” Other hurdles are involved as well—some expected; others, unknown. And some beyond the gear maker’s control. After all, these are first-time orders, fresh from the drawing board. Some examples:

“Availability of material at the time of order,” says Chinnusamy. “An originally planned process may not work out or special tooling and other requirements found at a later date may surface.”

Says FCG’s Young, “The biggest roadblocks when meeting deadlines come with make-complete projects (vs. cut-teeth-only). These delays are typically caused by the simple dependence on outside vendors. For example, we do not have heat treat capabilities in-house. Make-complete roadblocks are generally material availability, as previously mentioned, and vendor capacity and capabilities. Cut-teeth-only projects have fewer roadblocks, simply because there is less involved at our level. Of course, someone, somewhere along the manufacturing line still must deal with those types of issues, whether it is us or our customer. Dealing with those issues is something we do every day and something we are more than happy to provide to our customers.”

“Delays for material or vendor services,” says Mantei. “Although rare, rework or scrap, a job must be right or it’s not shipped. Our quality management system is ISO 9001 registered.”

“Some of the roadblocks for on-time delivery of a custom gear involve a number of variables, says Press. “Availability of material at the actual time of production, as opposed to the time of quoting, can be a problem for a custom gear. Additionally, the actual production schedule may differ from the time when the custom gear was estimated.

“Sometimes an outside source may provide pricing as part of the initial quoting processes. When the supplier receives the part, something was missed, and now price and delivery must be revised.”

“Of course, unexpected delays can occur because some requirement planned initially—internally or externally—cannot be achieved. Machine times, material substitutions, tools or inspection requirements also can become issues when the quoted gear actually is placed.”

At Xtek, “Our biggest roadblock is in managing priorities,” says Ryan. “We service a customer base where 100 percent of the gearing they order from us is custom gearing, and often, we receive requests for short cycle requirements (due to breakdowns /emergency outages). These are often at the root of missed deliveries for other customers.”

“It is always possible that job processes need to be changed for various reasons, and that can create delays because of scheduling conflicts,” says Schnarr. “But, if the designs have been finalized prior to starting the delivery clock, and raw materials are delivered as promised, meeting a delivery is not generally a problem.”

So when all is said and done, does custom gear manufacture yield fat profit margins? Is the risk worth the reward? The obvious answer—at least as far as these companies are concerned—is “Yes,” but not without risk.

“Custom gearing can certainly be considered high risk/high reward since customization allows for so many options,” says Young. “Of course, liability and profitability can be two sides of the same coin. Custom gearing is not always profitable. Of course, in a perfect world your profit margins are always high enough to allow for some error and people are perfect enough to avoid error. However, when you’re involving multi-million dollar machines, expensive exotic materials, and high precision labor, there are a lot of variables to be managed simply manufacturing the gear. Then, the gear has to actually perform as planned.”

“We do it every day with very capable employees, so the risk is mitigated,” says Mantei. “The reward is filling a customer’s need at a fair price. Most of the times, if it will turn into repeat work with larger economic ordering quantities, the prototype may be offered at a discounted price.”

“Any new program has inherent risk/cost factors, as it is sometimes difficult to evaluate expected performance,” says Press. “The associated risk/cost factors must be identified and evaluated before any significant efforts are expended. Working with exotic materials can increase risk. Sometimes materials, like a CVM300 steel, are difficult because they resist cutting, need special tools, feeds, speeds, etc. Hazardous materials, like beryllium-based ones, can be dangerous.”

Adds Precipart president John P. Walter, “Customers who come to us for the first time don’t necessarily take advantage of the engineering services upfront to minimize mistakes that many engineers make,” said Walter. “Obviously, it is best to consider customization up-front because it answers the question: Is this drawing a customer supplied really what is needed or expected? When we can work with customers honestly and openly, we have ended up saving customers time and money on their customized gear or assembly.”

Nevertheless, “Yes, custom products can be profitable,” Dress adds. “The programs that are profitable and successful are those that have been carefully and objectively planned, reviewed and controlled. They also have conservative expectations. Strategies, such as feasibility analysis, measurement of actual versus estimated progress, ongoing testing and inspection, milestone reviews and other techniques can be used to minimize risk and protect cost estimates.”

"Additional lead time is calculated in the delivery to hopefully compensate for new cutting and grinding tools, pattern development, rework as required and additional time for final inspection," Arvin explains. "In some cases prototyping may be required for custom spur and helical gears and, typically, always required for bevel gears. Currently, Arrow is working on seven new spiral bevel gear prototype developments for helicopters, jet engines and NASCAR racing. These include the CH53K Helicopter, XWB engine for the Airbus A350), etc.

"Regarding the recent custom gears Arrow Gear has made, we have been successful in predicting where the contact bearing pattern will go under full load for aerospace bevel gears before cutting the first chip-21 connective times. This is done by utilizing Gleason's fully loaded TCA, FEA, GAGE and CAGE software. This has saved our customers approximately one million dollars in bevel gear redevelopment costs and has allowed them to supply their products to their customers months quicker than would otherwise have been possible."

At Xtek, “Investment in machines and tooling is high,” says Ryan. “Competition is strong from both higher quality and local shops. The key to maintaining a profit in custom gearing is taking on work that you are good at. Accepting high risk work does not result in a high reward.

“Custom gearing is not always profitable. The manufacturer bears the risk for anything that goes wrong—material issues, machining errors, issues in heat treat, etc. Quality costs (scrap, warranty) are something that you cannot build into each order; it must be minimized and with costs spread out over all your business. Lastly, you must maintain a certain level of business to make it all make sense. Not always an easy combination—especially in down markets.”

“You have to do everything you can to minimize the risk,” says HMC’s Schnarr. “That means asking all the right questions, getting all of the fit and design detail prior to start. And making certain that the customer fully understands what he is asking for and agrees with what will be provided. The reward has to match the risk being taken.”

“Not every job has been profitable. Sometimes you have to eat cost to get the job done correctly, but over the long haul the confidence that we have developed with our customers makes for a profitable business relationship.”

"Yes," says Arvin. "(But), typically, money is lost on the first prototype gears, and what hurts the bottom line is when the customer takes our developed bevel gears and has another gear house do the production work."

For more information:
Joseph Arvin, President
Arrow Gear Company
2301 Curtiss Street
Downers Grove, IL 60515
Phone: (630) 969-7640
Fax: (630) 969-0253
www.arrowgear.com

N. K. “Chinn” Chinnusamy, President
Excel Gear, Inc.
11865 Main Street
Roscoe, IL 61073
Phone: (815) 623-3414
Fax: (815) 623-3314
www.excelgear.com

Kika Young, HR Director
Forest City Gear
11715 Main Street
Roscoe, IL 61073
Phone: (815) 623-2168
Fax: (815) 623-5193
www.forestcitygear.com

John Schnarr, Sales Manager
HMC Gears
Princeton, IN
Phone: (812) 385-3639 Ext. 252
www.hmcgears.com

Precipart
90 Finn Court
Farmingdale, NY 11735
Phone: (631) 694-3100
Fax: (631) 694-4016
www.precipart.com

Jim Mantei, VP Business Development & Operations
Vancouver Gear Works LTD
14551 Burrows Road
Richmond, British Columbia
Canada V6V 1K9
Phone: (877) 888-3111
Fax: (604) 270-1433
www.vangear.com

Xtek
11451 Reading Road
Cincinnati, OH 45241
Phone: (888) 332-XTEK
www.xtek.com