Breathing New Life, New Profits Through Reprocessing

Time, money and productivity can be realized when you rethink
current production methods

Jim Rowe
Mahar Tool
Supply

To many people in the medical device industry, the term “reprocessing” usually means the sterilization and repackaging of a device so that it can be reused. On the manufacturing floor, however, reprocessing takes on a very different and less controversial definition.  It means to retool or refine the existing production process of a part for improved productivity and profit.

In today’s competitive global environment, manufacturers of orthopedic equipment—from implants to instruments—are searching for more effective, efficient and cost-saving methods to produce parts. Some are finding that it’s possible to reap significant rewards by making a few small changes and applying some of the new technology in cutting tools, fixtures and machinery. The goal is to help the bottom line by saving enough time and money to be competitive, as well as stay on top of these cost-saving concepts for years to come.

To put the process in context, here’s an example.

A friend called recently and asked me to review some of his company’s lathe processes. His background is from a managerial/milling/manufacturing point of view, compared to my more technical shop perspective. He explained that he was given a task to provide more machine capacity for a growing product line without buying more machinery.

In the past, a typical answer to a capacity issue from his company was to buy more machines and then duplicate the process, no matter how efficient or inefficient the process was. This time he was asked to find the capacity by improving the process, which was established five years before the need for more capacity arose.

I began to review what currently was used at his shop to gain insight and provide some ideas. The organization was using a work cell consisting of three lathes, which typically carry a price tag of $200,000 or more, depending on options. The cell had worked overtime for the past three months to keep up with the demand. All three lathes made similar parts, which only differed in length. During my assessment of each lathe I noticed turning tools, drills, a carbide-tipped keyway cutter and a cutoff tool. Basically, the same process was followed to produce parts on each lathe.

Without targeting the program or work holding, I chose to upgrade the tooling. The obvious choice for the upgrade was the carbide-tipped key cutter. Five years ago, to create the feature on the part utilizing this cutter, the carbide-tipped cutter may have been the best choice available. This tool, however, runs slowly, the carbide substrate is hard and brittle and it is brazed onto the steel portion of the cutter body. In addition, there were variances between cutters at times, and changing them when they got dull often took 20 minutes to get them cutting correctly again—this process also contributed to the number of scrap parts during tool changeover.

Technology advancements in cutting tools in the past few years have resulted in insertable carbide-slotting cutters that mount on carbide shanks and, in this case, was a viable solution to my friend’s problem. The combination of rigid tool holding and tough carbide inserts increases cutting parameters, resulting in dramatically reduced cycle times. In this case, the existing cycle time was
25 minutes per part. The new cycle time with an improved cutter was reduced by 10 minutes.

Now, when there is a need to change the insert, the new piece repeats accurately onto the shank without any offset changes, reducing downtime and scrap parts. When added up, the improved time and parts produced, reduced scrap, saved labor and lack of a need for two more machines to meet production demands netted the company a savings of nearly $750,000.

Simply by knowing what to look for, the rewards from reprocessing can be substantial.

When to Reprocess

At what point in the lifespan of a product do you acknowledge that some improvements should be made to the manufacturing process? If the part was created in the traditional “prototype, first production order, hurry and meet the demand” type of cycle that we seem to be caught in these days, it is more than likely that part was created with some compromises in efficiency.

Obviously, manufacturers want to create a consistent and profitable process. Any shortcuts taken during the prototype stage, if not reviewed during a product’s infancy, can plague the system later in the life cycle. Assuming the lifespan of a product is several years, periodic review of production efficiencies will ensure that efforts to produce the product are still profitable.

The original launch team of a project will know where, if any, compromises in the current process exist. The team may have made a few decisions during the prototype stage to expedite the initial delivery of the product, while ultimately knowing there was a better solution. At the time, since delivery of a tool, fixture or machine was paramount, the group couldn’t wait long and the compromise would be dealt with later, if needed.
 
In fact, this type of circumstance may happen several times. Even when the prototype phase operates in an old-fashioned manner, it usually will provide a product good enough for the initial evaluation’s sake.

When evaluating how to improve the manufacturing process, it is important to look at the flow of each step that contributes to producing the end product.  It might be the manner in which raw material is stored or the handling of extra cutting tools and fixtures in the work area. It may be how a product is cleaned and inspected that needs attention. The steps involved in creating a work order or shipping paperwork also could need to be evaluated.

It may sound simplistic, but honesty is necessary in this step of reprocessing or your project won’t succeed—and there always will be something else that holds up progress and your total success.

  A common mistake is not identifying improvements soon enough. By letting old methods consume available machine capacity, the production’s needs override any time there might be to reprocess, which subsequently would enable more machine capacity. It’s a double-edged sword if you wait too long for the inevitable to take place. Remember to think about improvements long before you actually need them.

To help with long-term planning, here are a few occasions in which it makes sense to consider reprocessing:

• The demand for a product increased sharply and available capacity isn’t enough to keep up. Overtime helps to get more product out the door, but the labor costs of paying overtime are decreasing profit per part.

•    A new tool, fixture or programming technique on a similar product was used with great success, and it could be employed on another product line.

•    Part of a product’s launch plan is to invest in the latest technology once a certain demand is realized.

•    Competition from similar products in the marketplace forces the need to reduce cost and pass the savings onto the customer.

•    Accounting reports show a loss for every time a part is manufactured.
    
Whatever the reason, good instincts about how much better the product could be completed are enough justification to review current methods and evaluate the need to make a change. In making the decision to reprocess, it is important to fully understand the key elements that make up the process from start to finish.

The Prototype Phase

Machine selection. The prototype parts most likely were made on machines that had available capacity at that time or in a separate prototype department with older machines. Some shops now have identical machines in both the prototype and production departments. Most often, however, efficiency is compromised because the best machine for the job isn’t being used from the onset. These inefficiencies often are worked out later.

Tool selection. In some prototype departments, the available tooling consists of whatever is obsolete. Machinists will use whatever they can get their hands on at the time, regardless of whether that particular tool may be available again next week. Once again, efficiency is compromised because the latest technology was not used.

Design improvements. Most prototype departments produce a part to the initial design of a product. As the creation begins, the machinist might run into a problem with a certain feature on the part that is difficult to machine (eg, tolerances or shape), and a discussion with the product designer may occur to help resolve the issue. Going back to the drawing board might take place several times in the prototype stage. Of course, revisions can happen throughout the lifespan of the product. Some are improvements to make the manufacturing tasks easier.

End result. Once the initial parts are successfully completed to the print dimensions, production must begin in an efficient and profitable manner.

The Production Phase

Machine and tooling selection. The plan is to put the new product onto a machine that will complete the job in profitable and timely manner. The machine is then equipped with the proper fixtures, cutting tools, inspection equipment and staff needed to meet the production requirements, and you are satisfied with the overall throughput and profitability—time to let it run and make some money.

In this production phase, the tooling, fixturing and possibly the processing of the part may differ from what was used in the prototype phase—and for good reasons. At this point, you should trust the setup and tooling and not have too many troubles while the production is running.

The need to reprocess. The product is running the way it was designed to at the time of the product launch. You are still hitting rates that were set for the job more than a year ago, when the product’s sales were taking off, and forecasts for future sales are increasing. You applied the best available tooling, fixtures and machinery that were available at the time.

Now, an increase in demand has you running overtime to keep up with production requirements. This means the labor rate is getting higher per piece. The machine maintenance costs also could be rising due to more spindle uptime hours. This could eventually cause spindle downtime if preventative measures aren’t taken.

Several areas could lead a company to review the manufacturing process and begin looking for improvements. Whatever the reason to reprocess, some simple tasks are required to make sure the entire impact is understood.

Knowing Where You Are

As is the case with most journeys, you need a roadmap to lead you to your destination. But first, you need a good understanding of your starting point. Documenting the current process and related costs is an exercise that probably will surprise you. Most often, you will find that the current process is being compromised by certain factors—instead of getting frustrated, remind yourself that the initial goal originally was to simply get the product to the marketplace.

Creating a flow chart of the current process is recommended.  Comparing the old and new processes with a  flow chart is also an easy way to show improvements once you wrap up the project.

When making a flow chart, it is important to consider the follow-ing points:

•    How is raw material transported to the current machinery? How much labor (time) does it take?

•    How do the proper tooling, gauging, work holding, deburring, work instructions and production documentation all come together at the machine(s), and what is the related labor?

•    Tool tests are needed to be thorough and fair. Allow two to three tool manufacturers to present their ideas for a solution to reducing your product costs. Ask the tool rep for his or her documentation to authenticate your savings.

•    Record the current scrap rate and make the reduction of scrap a large focus of making a reliable process.

•    Include operators who will actually make the product in the reprocessing project. These are the people who probably know both the most productive and wasteful steps in the current process and also should make suggestions for future processes—after all, they have to live up to the expectations and cost savings that are targeted for the reprocessing project.

•    Submit a budget guideline and adhere to it so you know for this project—as well as future projects—how much these initiatives can cost and, more importantly, save.

•    Since needed improvements can result in certain additional costs, it is acceptable to reprocess in phases. After making one improvement, use the documented savings to provide the means to pay for the next phase.         

With this mentality, the improvements and project will stay on target and within budget.

So many contributing factors add up to the total cost of the product. For example, you could add a tool to create a chamfer or undercut in a part.     Yes, it will take a few seconds of machine time, but this change could eliminate the need for an operator to attempt to deburr an area that is difficult to reach. In the past, manual labor by the operator could have created a bottleneck in that area and reduced throughput for the entire day as the person tried to eliminate the burr by hand.

Weigh all of these thoughts when investigating a reprocessing project. Once you know the direction in which you’re headed, keep the map updated.     Take the savings from this project and apply it toward yet another reprocessing project. Once your company has completed a few reprocessing projects, you’ll wonder why you hadn’t started much sooner. 

Jim Rowe is head of tooling applications and medical accounts for Saginaw, MI-based Mahar Tool Supply Co. He has nearly 30 years of industry experience, with 10 years as a machinist, 10 years of machine shop management, and eight years in cutting tool sales, applications and training. Founded 60 years ago, Mahar Tool Supply Co. specializes in automotive tool management, as well tool management for medical implants and instruments. Mahar Medical is located in Warsaw, IN.