No manufacturer can claim to be a perfectly lean entity. After all, lean manufacturing is a never-ending practice of identifying and eliminating all sources of muda—lean-speak for waste. Companies can complete a wholesale "attitude adjustment," though, in terms of conscientiously hunting that which consumes resources but delivers no value to the customer. Crane Cams (Daytona Beach, Florida) is a good example of a company with this mindset.

This company started its lean transformation by reorganizing some of its existing equipment into cells to improve work flow and worker flow between machines.

Crane manufactures a number of aftermarket engine components and is the biggest racing camshaft maker in the United States. In some ways it resembles a contract shop, because it is not uncommon for customers to order a one-off steel billet camshaft (which currently requires 140 manufacturing processes) and to expect delivery in just a few days. In fact, this happens more than 25 times every week. Crane's lean journey started 7 years ago and was predicated on this need for quick delivery, as well as the reduction of work-in-process (WIP) that was eating away at the company's bottom line.

Since starting its lean transformation, Crane has lowered its scrap rate to 1.5 percent and decreased its product return rate to less than 2 percent, according to Len Plock, vice president of manufacturing. WIP for all its camshaft versions has been reduced from 9,000 to 3,000 pieces. The company has also cut manufacturing time for a small batch of steel billet camshafts from 126 days to 45 days, while maintaining a "smart" inventory of unfinished camshaft cores to meet its delivery goals.

On Its Way

Crane has reached a halfway point of sorts on its lean transformation, in the sense that it can look back on positive changes that have been made and look ahead with a more clear idea of what needs to be done to further improve work flow. Although the level of success borne from lean manufacturing varies from shop to shop, there are certain truisms that are common to nearly all lean transformations. Here are a few that have been substantiated by a company that finds itself on the lean 50-yard line.

• A lean transformation requires buy-in from all employees. For a lean push to be successful and sustained, a company's entire workforce must take on the responsibility of helping rid the company of muda in all its forms. This is possible with the right mix of people.

Crane recognized that its shopfloor workers would be apt to notice both small and large work flow problems, so it solicited their opinions about ways to improve upon the company's traditional manufacturing methods. This was Crane's first step toward lean manufacturing, and it also served as a means of getting all employees involved and interested in adopting lean principles.

Workers suggested grouping certain sequential-operation machines in triangular- and box-layout cells to provide easier maneuverability and part flow between machines. This initial effort was successful in reducing worker and part movement. It also allowed most cells to be operated by a single worker who assumed ownership of the cell and was responsible for maintaining quality.

This chance to directly influence the success of the company seems to drive those on the shop floor to stay involved and suggest changes. Open communication between management and shopfloor workers also helps eliminate the "us versus them" mentality and can help a lean transformation run more smoothly.

Traditional plate-style tooling was replaced with quick-change tooling for faster setups on some of the company's lathes. Reducing job change-over time is vital to any lean push.

• Technology consultants can speed a lean start-up.While there is a wealth of information available about lean principles for anyone with the gumption to learn and apply them on their own, many shops may not have the time to quickly become lean experts. That's when a lean consultant can be very helpful.

After its own initial efforts, Crane sought assistance from the Florida Manufacturing Enterprise Partnership (MEP). According to Bob Horvath from Florida MEP, Crane Cams underwent a traditional four-stage lean program. The first step was to host introductory lean seminars for every Crane employee. Crane's president and CEO, Gene Ezzell, spoke before each seminar to demonstrate his support of the exercise. "Mr. Ezzell has always been very proactive when it comes to maximizing efficiency in all areas of the company," says Mr. Plock. "Once he learned how helpful lean manufacturing would be to both the employees and company, he had everyone attend the lean seminar to learn about the concepts of improving work flow."

The next step involved process examination and preparation of value stream mapping for both present and future states. Following that, kaizen events were held for selected product lines and for an assembly/packaging cell for roller rocker arms. To date, four kaizen events have been held. During each event, small, cross-sectional teams are trained for a few hours. These employees then bring the strategies they learn to the work area to determine how they can be applied. The final stage, consultant mentoring, is ongoing support to the company as lean changes are implemented.

• A lean transformation doesn't require the immediate purchase of new machines. Like many lean transformations, Crane started with the equipment it had. This highlights an important point about improving work flow. In many cases, the speed that a machine can make a part often is not as important as how efficiently parts are delivered to, and moved in and out of, the machines. Therefore, a more efficient machine might not be immediately necessary.

Supermarkets smartly stocked with nearly completed camshaft cores are the key to quick delivery of custom camshaft grinds. After an order is received, the camshaft lobes are ground and the part can be immediately shipped.

However, machine downtime has to be monitored closely, especially with old equipment, as it can become a significant work flow bottleneck. Crane has implemented a Total Productive Maintenance (TPM) program to quickly resolve repair issues. When downtime becomes too excessive and/or replacement parts are increasingly hard to come by, a new or rebuilt machine purchase becomes the next logical step.

• Setup reduction is a lean staple. Most of Crane's machines, including its tracer grinders and lathes, were originally used for extended production runs. "It's easy to plan a long run; you just tool up and go," says Mr. Plock. However, lean is based on a build-as-needed system of shorter runs and quicker change-overs. Crane now uses quick-change tooling systems from Iscar (Arlington, Texas) on some of its Fay lathes, which has cut tool changeover to a fraction of the time that it took to change the old plate-style tooling, thus facilitating small-batch production.

• No two lean programs are the same. Even though the same lean tools may be used, companies can apply them in different ways. For instance, Crane uses a modified version of the one-piece flow concept, in which a batch of 40 camshafts is considered one piece. "One-piece flow forces us to run the next job in line," says Mr. Plock. "We're not jumping ahead and doing parts that aren't needed because the setup might be easier, for example."

• Supermarkets are not just for bread and milk. To say that Crane is making the transition from batch production of its billet camshafts to a build-to-order approach is not quite accurate. It is more a move to smarter, smaller batches and a sort of pre-build-to-order methodology. That's where its supermarkets come into play.

The supermarket concept forms an inherent pull mentality, in the same way that empty shelves at a grocery store trigger more foodstuffs to be ordered and stocked as needed. Crane's supermarkets stock a variety of pre-machined camshaft cores, which it can quickly pull and then grind the lobe profiles for fast delivery. This is how a custom billet camshaft that takes 45 days to produce can be delivered in just a few days.

This new HMC eliminated a work flow and setup bottleneck by replacing two older machines. The billet camshafts shown will be used in 7,500-hp top fuel dragsters.

The trick is figuring the optimal amount of cam cores to keep in each supermarket. Crane has the advantage of somewhat predictable customer buying seasons, so it can follow sales trends and forecast demand to determine how many and what types of camshaft cores (Chevrolet, Ford, Harley Davidson and so on) to maintain in the supermarkets. Crane typically starts restocking its supermarkets in the fall to get ready for spring and summer racing seasons.

• A perfect work flow situation may never be achieved. Most existing facilities were not set up with lean manufacturing in mind, and some equipment may not be able to be relocated because of safety or regulatory issues. In these cases, an ideal work flow situation may not be attainable. Crane mixes a variety of processes, such as copper plating, heat treatment and carburizing, between machining and grinding operations of its cast and billet camshafts. Much of that equipment would be impractical, if not impossible, to move. Knowing this, the company has done its best to move its milling machines, lathes and grinders into cells to best optimize work flow.

• Lean uncovers other bottlenecks and waste. As work flow improves, previously unnoticed or insignificant waste becomes more apparent, as do possibilities for improvement. The two main improvement areas Crane is investigating are robot load/unload and machine replacement with more flexible models. This phase has started with the recent purchase of a new HS-1 horizontal machining center from Haas Automation (Oxnard, California), which has replaced two older machines. Combining machining capabilities into one machine allowed cell reconfiguration so that one operator could run both the new machine and a lathe.

Crane is also looking at multitasking machines, which would allow milling and turning operations on one machine to drastically cut the time required to make a billet camshaft.