Presented at Moldmaking '99
May 1999

Rapid Prototyping as a Competitive Weapon

Good, fast and cheap...pick any two. Just a few years ago, this bit of wisdom was true. The customer knew that the combination of top-quality and rapid delivery demanded a premium price. This is now far from the truth. Today, the customer expects tools to be built, and parts shot, not only with quality and speed but also with low prices.

The tooling and molding industries are extremely competitive. The customer is pressing for improved speed, quality and cost. Competitors are everywhere, both in the United States and overseas. Just to remain status quo, you have to constantly improve your processes and incorporate new technology.

Rapid prototyping (RP) is a tool that can be used to help you compete in the areas of quality, delivery and price. It is also a tool that can help you strengthen another area of competitive advantage, customer service. RP can be your competitive weapon.

What is Rapid Prototyping?

RP is a collection of technologies that construct models, prototypes and patterns directly from digital data by "growing" the prototype layer-by-layer.

The creation of the prototype begins with three-dimensional CAD data, either a surfaced wireframe or solid model. The CAD model is used to export a 3D representation of the design in a file format called STL. This STL file is accepted by all RP technologies, eliminating the need to possess numerous CAD packages.

To prepare the STL file for building, it is sliced into thin horizontal planes, typically at 0.004" to 0.006". These slices become the individual layers from which the prototype is grown.

RP acts much like a 2 1/2 axis machining operation; but instead of putting chips on the floor, it adds material. The process starts with the bottommost layer. The layer describes a "tool path". A "tool" follows this path to solidify material to create a single, solid layer of geometry. This process is then repeated for the second and subsequent layers, bonding each layer to the previous one.

The tools, and the materials used, vary widely across the available technologies. Both stereolithography (SLA) and selective laser sintering (SLS) use a laser as the tool. In SLA the laser cures a liquid resin, while in SLS it fuses powdered materials.

The additive nature of the process allows all geometry to be seen on each individual cross section. Since the geometry is always available to the tool, the level of complexity that can be constructed is limitless. For example, RP can easily produce a sphere contained within a sphere, in one operation, without the necessity to bond individual pieces.

Unlike other, more conventional processes, time and cost are determined more by the size and mass of the component than by complexity. Therefore, difficult prototypes are delivered in days, not weeks, and frequently at less expense than traditional methods.

To oversimplify the benefits of RP, it is a technology that increases the availability of a prototype. With the speed, and cost effectiveness, RP delivers a model well within the constraints of project deadlines and budgets.

Improved Communications

With the acceptance of the statement that RP's key benefit is that it makes prototypes increasingly available, there is only one other benefit, and it is common to all prototyping methods. Tangibility is the key benefit of any prototype. The ability to see, hold, and touch a physical representation of a component's design turns the nebulous, ambiguous, intangible nature of blueprints and CAD data into something real.

The physical, tangible model eliminates guesswork and assumptions. It clearly communicates the designer's intent and form. And, it can communicate the design to both technical and non-technical personnel. The design information is immediately available to everyone: shop floor, sales and marketing, and executive management. The design is also rapidly and easily communicated to everyone within your client's organization.

What would you rather work from; blueprint, CAD data or a physical model? How much easier would your job be if you did not have to decipher the design intent of a blueprint or the bird's nest of lines, arcs and splines in a 3D IGES file? How much better and faster could you do your job?

Both blueprints and CAD lack tangibility. Without the capacity to hold a prototype, we increase the opportunity for ambiguity, uncertainty and confusion. Blueprints and CAD data can contribute both to delays in communicating a design and to the delivery of inaccurate information. The failure to communicate properly leads inevitably to problems that directly affect your ability to delivery a quality product quickly and cost effectively.

Even with the highest level of CAD, a solid model, there remains a lack of clarity. An attractive shaded image of a component can fool the eye. An optical illusion or oversight may lead to incorrect assumptions of the component's design. To fully communicate the design, the onus is on you to first detect an important design element then to interrogate it. It is your responsibility to pull dimensions from the model where it is necessary and appropriate.

The most obvious example of a CAD solid model's lack of clarity is demonstrated when you view the data on a computer screen. To scrutinize the model, it is maximized to fill the screen. This means that a dime is represented to the same proportions as a battleship. Both are contained within the same 19" window. After reviewing the file for an extended period of time, you can lose appreciation for the true size and scale of the component. You tend to forget that the dime is measured in fractions of an inch, while the battleship is measured in hundreds of feet.

2D drawings will yield even more difficulties than CAD data. How easily and clearly do they describe a design? It is laborious to evaluate a part that is documented on five "E" size drawings. It is tedious to reference the top view on "sheet 1 of 5" to determine what view "G", on sheet 3, is describing. A simple omission of a hidden line can radically affect the definition of a component.

If you find that a blueprint is ambiguous or inaccurate, it is difficult to clarify and rectify the problem. First, through time consuming analysis, you must confirm that a conflict or problem exists. Then, you contact the client to describe and resolve the problem. Verbally directing the customer to the feature in question can be frustrating. When you and the client are finally looking at the same feature, they frequently disagree that there is a problem, because they expect to see on paper what they have already created in their mind. After the client agrees that there is a problem, you wait hours or days for a response on the correct design.

RP, on the other hand, quickly, clearly and easily communicates the details of a part. With an RP model, two views can not represent conflicting information. The prototype is an exact description of the intended design, generated directly from the client's data. RP is a perfect complement to the stack of blueprints and the CAD data. RP provides an unmatched ability for you to determine what it will take to do the job right.

RP is a communication tool. Good, clear communication is fundamental to doing the job right. Good, clear communication is the fundamental element to doing a project good, fast and cheap.


The difficulties in communicating from CAD data and blueprints are first experienced when responding to an RFQ (request for quotation). Each previously described scenario presents barriers to a quick delivery of an accurate quotation. But, when quoting a project, there are even more opportunities for communications to adversely affect the process.

If you are to quote from electronic data, delays and frustration are likely. The first step is to negotiate the type of data that will be sent. You evaluate the file types that you can accept and the file types that the client can generate. Perhaps the client has a solid model in Pro/Engineer, but your internal CAD capabilities are limited to Unigraphics. Therefore, the original CAD file cannot be directly transferred. So, you agree to a 3D, trimmed surfaces IGES file.

Now, you have to arrange for the file transfer. You and the client agree that the file is too large to email. Your client cannot FTP the data to you because of corporate firewalls. So, now you're looking at either a modem transfer or overnighting the data on an electronic medium. You try the modem, but after an hour you still cannot establish communications. Now, the only option is to overnight the data. After working with the client for hours, you now expect good data 24 hours after the process began.

The data arrives the next morning, as promised. When your computer guru opens the file, he finds that the data does not look right. The diagnosis: incompatibility between the IGES entities exported and those that you can read. In the worst cases, this cycle repeats itself for what seems like an eternity. Meanwhile, the clock is ticking on the deadline for quote submission, and the client is telling you that he has not had this problem with any other vendor.

If this rings true for some of your quotations, you could easily solve it with an RP model. If the client supplies the RP, the most difficult part of the process is getting the shipping information correct. If you are having the RP built, you delegate the data transfer and file generation to experts that do these operations many times a day.

Once you have secured the design data, the quoting process can begin. Your quoting department is always busy and always being pressured. There is a huge stack of projects to quote. The client, the salesman, and the manufacturer's rep are all calling to get their quote today.

Working from blueprints or CAD data, there is likely to be uncertainty. Often, you can guess the client's intentions. With the time constraints and deadline pressures, what happens? Do you always do the right thing by contacting the customer to determine what is really happening or required? Frequently, you do not. You know that it will take a lot of time to get the answer. You also know that the clock keeps ticking on the deadline for all the quotes promised to all of your customers. What do you do? You assume. And, you know the cliché about assuming.

With the assumptions, you must be conservative to ensure that the company is financially covered. You add a little time and money. If you do this several times for several different features, the costs can add up. You may find that you have done such a good job of protecting the company that you have priced yourself out of the ballgame. The client informs you that you were 25% higher than the competition, all because the other shops saw a simpler route to the tool design. Your sales force most likely responds that they do not have that large of margin to give away. So, they stand firm. You lose the job, when you may have been able to price competitively if you had the right information.

The opposite scenario can be even worse for the company. What if you do not see a "lock", and you don't add a side pull to the tool design? You now win the job because you are much cheaper than the competition, but you pay in the end. The problem is detected when the job begins, but you have to live up to the quoted price. Now, the company loses money.

Securing an RP model will make your company more powerful, effective, productive and responsive when addressing an RFQ. By clearly illustrating all design features and the true design intent, without ambiguity, the component can be quoted efficiently and accurately. The physical model eliminates assumptions and misinterpretations. It also reduces the time spent in gathering and interpreting the design data.

The physical RP model can be held, evaluated and probed. It can be used as a visual aid when discussing tool design options with other members of your staff. The RP model is an aid in delivering the best tool and parts for your client's requirements.

RP helps you to be good, fast and cheap, all while delivering the profits desired by your company. You can sharpen your pencil to a fine point and not sacrifice profit on the job.


Upon a thorough analysis of the process and work flow, many find that a significant amount of time is consumed by unproductive activities. Rather than putting chips on the floor, the work is held in queue for the next process to become available, or it is put to the side awaiting further instruction or information.

An RP model can assist in more accurately predicting cycle times for each process. With improved estimates, surprises and padding can be reduced. This in turn allows for the creation of a tighter, time-compressed schedule that remains realistic. The bottom line is that unproductive queue time can be significantly reduced. Taking this fluff out of the schedule will have tremendous positive impact on your ability to produce tools and parts in an accelerated timeframe.

Questions on the shop floor, regarding the design, procedures or process, can delay the cycle time. By making an RP model available to all employees, these questions can be quickly and accurately addressed. Without the delay of interpreting blueprint or CAD data, the employee can evaluate the physical model to determine the requirements and the answer to the question that is delaying the process.


Rework, originated by the customer, impacts your business in two ways. First, it affects your client's perception of your organization. Second, rework has significant, negative impact on your shop's productivity and profitability.

Outsiders commonly assume that rework is a huge source of profit. Some even believe that shops will low-ball a quotation with the expectation of recouping the revenue through rework. The belief is that the vendor knows that they have the client over a barrel. Since it is unlikely that the job will be taken to another shop for rework, the vendor takes advantage of the situation by charging exorbitant fees.

Rework charges may be expensive and appear to be excessive. But, the charges are reasonable, considering the impact on overtime, schedule manipulation and delays imposed on other orders. Even with a higher price for rework, it can still have a negative impact on your bottom line.

Your client is not fully aware of the rationale behind rework charges. They have the feeling that your company has taken advantage of the situation. The client is left with a negative perception of your organization. This attitude could then result in a review of competitive shops for future work.

Rework affects your internal operations. It is difficult to slip new work into a busy schedule. It is much more difficult to fit unexpected rework into a schedule that has already become unmanageable.

To meet the expected deliveries, on all your jobs, requires manipulation of your current schedule. Changing the schedule in mid-stream results in lost efficiencies and higher cost of operation. Pulling resources from one job to another can also create internal discontent. These, and many other negative results, only serve to decrease your organization's ability to quickly and cost-effectively deliver competitive product and services.

RP's quick, clear communication has already been discussed in its ability to drastically improve the quoting process. During the quotation phase it can also be used to detect design modifications that will protect the customer. With RP's clear representation of a design, it provides you an enhanced ability to evaluate the component. It also enhances the ability to visualize the tool design that will produce the part. This, in turn, makes it much more likely that desirable modifications can be identified.

With RP, the amount of rework can be reduced. Not only can you avoid problems that affect the quality of tools and parts, but you can also help the client to avoid problems caused by their designs. By simply acquiring an RP model, you can increase the manageability of the schedule, decrease profit erosion, and improve the consistency of on-time delivery. RP will also yield greater client satisfaction, since they do not have the opportunity to develop negative perceptions of your company from rework charges.

Customer Service

Even with the best delivery, price and quality, customers can still be lost to the competition as a result of poor customer service. Customer satisfaction is a relative term for each individual. But, overall it can be stated that customer service is derived from the value that you add in the process and from the ease in doing business with you.

A customer recognizes added value when input is provided on their design such that they avoid problems or reduce cost. When your organization is the one that consistently provides feedback on the design, the customer perceives added value. These recommended modifications might save the customer from producing a bad part that results in additional time and money for rework. The suggestions may also allow simplification of the tool to reduce overall cost and time. Value-added services will make your company stand out from all the other competitors. RP is a powerful tool that enables you to add this value to every job.

The easier you make the communications between you and your customer, the easier it is to do business with you. The use of an RP model can speed and simplify customer interactions. Use the RP as a clear, concise communication tool for a face-to-face review meeting with your client. The RP model becomes a visual aid that everyone can easily understand. You have made it easier for your customer to do business with you, and you also demonstrate that your company employs the latest in technology to get their job done quickly and accurately. This translates to less demand on your customer's time and less frustration, fostering the perception that you offer excellent customer service.


RP is a simple tool that has tremendous, positive impact on the quotation process, scheduling, rework and customer service. There are many other areas of your business that RP can assist, but they are too numerous, and perhaps too unique to your company, to describe. But, the benefits are worth seeking out, because they can help you to become more competitive.

RP is merely a communication tool. The physical, 3-dimensional model quickly and clearly illustrates the design intended by your customer. This clarity not only reduces errors and problems, but also maximizes the potential to discover new and better ways to attack the project.

The tangible model is available in just days. Independent of design complexity, RP rapidly delivers the prototype to make it an available tool for each of your projects.

There are three strong options to gain access to this competitive weapon. If justified, you may choose to purchase the equipment for use in your shop. You can also purchase RP services on an as-needed basis. Finally, just ask your client if they have an available RP model. Each of these options will cost-effectively put a prototype in your hands in just days. Each of these options will allow you to deliver top-quality products rapidly and cost-effectively. You will have the competitive edge by giving the customer what they demand...good, fast and cheap.


Contact information:
printer friendly version Todd Grimm
T. A. Grimm & Associates, Inc.
3028 Beth Court, Edgewood, Kentucky 41017
Phone: (859) 331-5340      Fax: (859) 514-9721


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