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Articles from 1997 In March


Practical Remedies for Thermoset Surface Defects

Does this scene sound familiar? A noticeable surface defect occurs during moulding or trials. The problem has to be solved, and so it is, often by trying various options until something clicks. Afterwards, the solution and the steps needed to reach it are generally forgotten - unless the same problem occurs again, and the same people happen to be there to solve it. If the problem solvers are not there, or if it's a different problem, the whole process is repeated. This kind of wasteful repetitious problem solving would not occur if previous solutions were saved, organized, and easy to find when needed.

The professionals at the Kunststoff-Institut für die Mittelständische Wirtschaft (KIMW) in Lüdenscheid, Germany, have researched and catalogued the 25 most common surface defects found in injection and compression moulding of thermoset materials. They have also summarized the most probable causes for each problem and created systematic troubleshooting guides for injection and compression moulding.

Following are five of the most common surface defects, followed by their causes and the troubleshooting guide for injection moulding.


Porosity. Individual grains are
clearly visible (above). The surface
of porous areas is rough and appears
duller than the rest of the surface (below).

POROSITY

Description: Uncompressed areas appearing mostly at the end of a flow path or around weld lines, also at domes, ribs, and thin-wall areas. The surface is rough, there are gloss differences, and melting is incomplete, possibly with colour changes.

Cause: Mostly insufficient compacting of the moulding compound. Possible reasons include low shot volume, insufficient pressure transfer, insufficient venting to allow volumetric filling (possible diesel effect).

Troubleshooting:

Residual melt cushion too small?

If Yes...

  1. Increase backpressure.
  2. Check steadiness of plasticizing time (bad feeding, no material in hopper).
  3. Check mould temperatures (control fluctuation).
  4. Run process with melt cushion.

Other possibilities:

  • Minimize temperature fluctuations by better thermal design (position of temperature sensors/cartridge heaters, better control).
  • Avoid restricted flow areas in gating/feed system.

If No...

Sink marks directly after moulding?

If Yes...

  1. Increase metering stroke.
  2. Increase injection pressure.
  3. Increase holding pressure.
  4. Increase holding time
  5. (check part weight).

  6. Reduce injection rate.
  7. Adopt ventilation program.

Other possibilities:

  • Check moulding compound
  • iscosity, reactivity.

  • Install ventilation.
  • Enlarge gates.
  • Check screw wear.

If No...

  1. Check ventilation, clean if needed.
  2. Check temperature distribution in mould and adapt.

Other possibilities:

  • Avoid restricted flow areas inside mould.
  • Check gating/feed system geometry for evenness, change if needed.


Blister. Swollen surface of a moulded part.

BLISTERS

Description: Blisters are gas inclusions that can cause deformations on the surface of the moulded part. They can appear as large areas spread over the entire moulded part (undercuring), or as small blisters (overcuring, pimples, fish eyes) that can be either local or spread over the part (outer layer cures too fast). Not to be confused with elevations, which can be the result of mould damage, blisters do not always appear in one place.


Small blisters result from the
outer layer curing too fast (above).
Blisters do not always appear in
one place (below).

Cause: Small Blisters. Pimples or fish eyes, as they are often called, occur when the peripheral layer cures too fast compared to the rest of the part and volatiles in the compound cannot escape during curing. After demoulding, the pressure gradient forces the gas incursions toward the outer layer but the high crosslinking permits only slight swelling or bulges.

Cause: Large Blisters. The peripheral layer of the part does not completely cure and remains soft. When gas pressure forces volatiles in the compound to the outer layer, lack of counter pressure allows large-area swelling or cracks.

Troubleshooting:

Do small blisters appear (pimples, fish eyes)?

If Yes...

  1. Reduce mould wall temperature.
  2. Check temperature distribution in mould.
  3. Reduce curing time.
  4. Reduce injection rate.
  5. Increase holding pressure.
  6. Increase holding time.
  7. Apply venting cycle/check venting.
  8. Increase cylinder/nozzle temperature above 100¡C (212¡F) only if using polycondensating moulding compounds.
  9. Optimize back pressure.
  10. Optimize screw speed.

Other possibilities:

  • Use drier compounds, possibly pre-dried.
  • Optimize evenness of mould heating.

If No...

Do large-area blisters appear?

If Yes...

  1. Increase mould wall temperature.
  2. Increase curing time.
  3. Check temperature distribution and adapt if needed.
  4. Optimize injection rate.
  5. Increase backpressure.
  6. Increase screw speed.
  7. Increase cylinder/nozzle temperature above 100¡C (212¡F) only if using polycondensating moulding compounds.

Other possibilities:

  • Use drier moulding compounds, possibly pre-dried.
  • Decrease nozzle diameter.

CRACKS

Description: Small gaps that often appear near gates, wall thickness variations, weld lines, restricted flow areas, blisters, inserts, or sharp edges.


Cracks at the gate of an
ashtray (above) Cracks at
openings (below).

Causes: Anisotropic shrinkage, varying temperatures, and prevented or obstructed shrinkage of gas incursions can cause internal stress. External stress can come from demoulding forces, undercuts for example, or from mechanical forces. The internal stress caused by shrinkage onto the core during curing can result in stress peaks in areas such as corners and thickness variations.

Cracks at the gate can result from the stress differences caused by the pressure gradient between the gate and the end of the flow path during filling. Since the material has cured at the cavity wall, cracks can appear in areas with the highest pressure. In a filled cavity, the holding pressure can exert enough force on the already cured gate area to cause stress cracks.

Stress cracks can also be caused by strong force during the demoulding of parts with tunnel gates or by a pressure gradient in the feed system caused by material backflow. The cause of the latter is holding pressure that is too low, too short or nonexistent.

Before troubleshooting, the following inspections should be carried out:

  1. Check mould for temperature differences, which should be less than 5°C (9°F).
  2. Are cracks caused by undercuts?
  3. Draws should be large enough.
  4. Check if ejectors are causing large deformations.
  5. Optimize injector speed.

Troubleshooting:

Do cracks appear near gate and is part completely compressed?

If Yes...

  1. Lower holding pressure.
  2. Decrease holding pressure time.
  3. Decrease injection rate.
  4. Optimize changeover time.

Other possibilities:

  • Use material with less shrinkage.
  • Enlarge gate.

If No...


Stress crack caused when
shrinkage onto a core
is prevented.

Do cracks appear near sharp edges, bypasses, cores, or restricted flow areas?

If Yes...

  1. Decrease injection rate.
  2. Optimize holding pressure.
  3. Optimize holding pressure time.
  4. Increase backpressure.
  5. Increase screw speed.

Other possibilities:

  • Avoid sharp edges and by-passes.
  • Optimize gate type and position.

If No...

Do cracks seem due to shrinkage differences caused by material accumulations such as near wall thickness variations, domes and ribs?

If Yes...

  1. Increase holding pressure.
  2. Increase holding pressure time.
  3. Increase injection rate.
  4. Increase cylinder nozzle temperature to >100°C (212°F) for polycondensating moulding compounds.
  5. Increase backpressure.
  6. Use smaller machine nozzle.
  7. Optimize mould wall temperature.

Other possibilities:

  • Pre-dry material or use compound with less shrinkage.
  • Enlarge gates.
  • Smooth mould wall if too rough in direction of demould.

If No...

Are inserts used?

If Yes...

  1. Preheat inserts.
  2. Increase holding pressure.
  3. Increase holding pressure time.
  4. Decrease injection rate.
  5. Decrease mould temperature.


Cracks. Restricted flow area
in front of a core.

If No...

Apart from the cracks, is there excessive flash?

If Yes...

  1. Consider stiffening mould.
  • Provide center support.
  • Insert intermediate plate, etc.

If None of the remedies has helped...

Other possibilities:

  • Injection-compression moulding.
  • Compression moulding.

Restricted flow zones include in front of cores and domes, around ribs, etc. For example, moulding compound flows farther in front of a core, but next to the core the cavity fills faster and high temperatures occur. The compound in these restricted flow zones cures faster than in flow areas. The different levels of crosslinking in the resulting phase boundaries result in shrinkage and cracks.

CLOUDS


Clouds are created according
to the theory of wave propagation

Description: An area of the part with boundaries transverse to the direction of flow that appears matte compared to the rest of the surface. This defect often occurs around gates and after wall thickness variations. Often these clouds can be wiped off.

Causes: Lubricant content in the moulding compound is too high. Short pressure releases - for example, the switchover from injection to holding pressure or a wall thickness variation - cause lubricant deposits to settle at the flow front. During injection, the pressure drop allows this excess lubricant to penetrate into the moulding compound. At first it surrounds the injection point and then settles, in the case of a frontally flowing moulding compound, on the mould wall.

Troubleshooting

Does the defect appear near the gate?

If Yes...

  1. Avoid pressure relief during changeover from injection to holding pressure.

  2. Cloud formation at a pin gate

  3. Reduce injection speed.
  4. Optimize changeover point.
  5. Reduce mould wall temperature.

Other possibility:

  • Reduce lubricant content in moulding compound.

If No...

  1. Reduce injection speed during cavity filling.
  2. Reduce mould temperature.

Other possibility:

  • Reduce lubricant in moulding compound.

COLOUR STREAKS


Color streaks clearly show
where two flow fronts meet
behind an opening.

Description: Streaks visible on the part surface as discolourations. They are oriented either as oblong stripes (e.g., in restricted flow areas) or transverse to the flow direction (at the flow front).

Causes: Colour streaks are the result of uneven distribution of the material components (small or still highly viscous) or of different orientation of the colour pigments on the surface of the part. Thermal damage of the moulding compound can also cause colour changes.

Troubleshooting:

Is the moulding compound contaminated or has the batch been changed?

If Yes...

  1. Use cleaning material to clean the hopper.


This cloud along the boundary
of a restricted flow area, transverse
to the flow direction, could easily
be mistaken for streaks.

Other possibilities:

  • Check moulding compound for contamination.
  • Reduce dust content in surrounding air (grayness).

If No...

Are mould or screw worn?

If Yes...

Other possibilities:

  • Change screw or rework mould.
  • Possibly coat mould.
  • Adapt moulding compound, e.g. round off glass fibers.

If No...


Colour streaks. Shearing of the
compound in a restricted flow
area permits material component
to lodge against mould wall.

Are colour differences a result of thermal change?

If Yes...

  1. Reduce injection speed.
  2. Increase machine nozzle diameter.
  3. Reduce backpressure.
  4. Reduce rotational speed.
  5. Reduce mould temperature.
  6. Check temperature distribution.


Colour streaks. Stretching effect
at the flow front. 'Foreign' material
particles are stretched and moved
toward the mould walls both in the
direction of flow and transverse to it.


Other possibility:

  • Avoid sharp edges and transitions.

If No...

  1. Increase backpressure.
  2. Increase injection rate.
  3. Increase cylinder/nozzle temperature.
  4. Increase screw speed.

All 25 problems and solutions are in a compact handbook: Guide to Surface Defects on Thermoset Compression and Injection Moulded Parts, available in English from the IMM Book Club. Call (1) 303-321-2322 or fax (1) 303-321-3552 for ordering information, or write Deb Golanty, IMM Book Club, 55 Madison St., Suite 770, Denver, Colorado 80206, USA.

Contact Information: Kunststoff-Institut Mrs. S. Köhler or Mr. G.Oussios Karolinenstraße 1 58507 Lüdenscheid, Germany. Phone: (49) 2351 1064 191 Fax: (49) 2351 1064 190

Talks With A World-class Purchaser

Many multinational OEMs in different markets are finding it best to "think globally and act locally." In automotive, the so-called "world car" has arrived, a standard global design involving resins, modular parts, and moulds that may be sourced in different regions around the world. What is involved in such world-class purchasing efforts today? What is expected of part and mould suppliers?

To find out, IMI recently spoke with Guy Sterkens, global purchasing manager of Philips Singapore Pte. Ltd. (Philips Sound & Vision, Singapore). Sterkens came to Philips from General Motors Corp. There he worked in purchasing for the well-known negotiator J. Ignacio Lopez, and learned "how not to do things," as he says. Sterkens has been instrumental in helping Philips launch its "world television," its first standard global product with regional supply requirements that goes into production in Brazil, the U.S., and Europe this year. Here is what he had to say:

INJECTION MOULDING INTERNATIONAL: Why did you come to Philips?

GUY STERKENS: When I was at GM, Philips was one of my suppliers for speakers. It was lacking in global purchasing expertise and I was looking for a career in the international marketplace. I started with Philips Sound & Vision in Eindhoven in October 1995 and am, today, globally responsible for plastics, parts, and moulds for its video, audio, and TV products.

IMI: Why did Philips want a world TV?

STERKENS: BGTV [Business Group TV, part of Sound & Vision, Singapore] wanted to restructure. It wanted to centralize development and reduce and consolidate the number of components required to reduce time to market. Philips wanted to develop a global standard for TVs, with one centralized design center in Singapore at the BGTV factory, where the company has been for 20 years, and one design suitable to regional requirements. And, it wanted a more flexible, preferred supplier base.

We see to it that a good supplier stays healthy. With fewer suppliers, you can give a bigger slice of the cake to each supplier. This may involve lower piece prices and profit margins, but it means more long-term business for moulders. The world TV has been a successful project, involving substantial cost reductions. From now on, all projects will follow this procedure.

IMI: What kind of moulders were you looking for?

STERKENS: Moulding is more or less regional, and involves many transparent costs. You have to rely on the existing supply base in an area, and it is difficult to quickly move away from one supplier that has dedicated volume and capacity. I might try something like persuading moulders to do subassemblies, but I do not force suppliers into doing things they cannot do, like gas-assisted moulding. When you do that, you create problems for yourself in the end. You have to find a moulder willing to share benefits. We check in on moulders every four to six months to discuss the best practices, maybe in cycle reductions through better cooling. We ask for their help up front and during the project.

IMI: How do you find these moulders?

STERKENS: You check their Dunn & Bradstreet listing. A moulder may come back with a cheap piece price, but may be gone in six weeks. You want the company to be financially healthy and cost competitive. You do not want a moulder with no other outside business. In our case, gas-assist capability also was a primary concern. We do not chase global labour prices, because we want part quality to be stable. We stay loyal to a moulder as long as possible, especially for larger parts like TV cabinets.

We try to promote in-house tooling at the same location where we source parts. Fu Yu [Fu Yu Manufacturing Ltd., Singapore], one of our best suppliers, has in-house mouldmaking. You cannot expect every moulder to have it, but if it is available, it is welcome.

Regarding quality, we are introducing six Sigma-type standards, like Motorola. Fu Yu also supplies Motorola. Such standards are a general trend in the marketplace. We negotiate PPM levels and make sure that quality is built into the mould. We do not specify equipment for suppliers, or tell them they must only use one brand of machine. It is no longer possible to do that. And we talk to machine operators, the people who do the trial moulding, to see what they think of the mould.

IMI: If you could do the world TV project all over again, what would you do?

STERKENS: I would have everyone come in before we start the design. You need input before, not after the design starts. If not, you can lose three to four weeks in the cycle, and, with time-to-market pressures being what they are today, it is not easy.

Design and Material Development for an Ice Skate Blade

The rapid growth in material and processing technology makes it essential for plastics manufacturers, mouldmakers, and designers to keep in close touch. In the development of plastics components, the properties of the material and its processing behaviour should be taken into account right at the draft

Figure 1. A dynamic biomorphic design and
specially selected material combination together
produce the lightest and fastest skate blade yet.

design stage. In this example, material and technological studies of frogdesign, a design agency in Altensteig, Germany, and of WST, a manufacturer of sports articles in Villingen-Schwenningen, Germany, led to the selection of a suitable plastic and to a creative design for an ice skate blade (Figure 1).

Extreme Demands: Material

The blade of an ice hockey skate produces frictional heat through pressure and movement, causing the ice to melt and a film of water to form between the blade surface and the ice. It is only this film of water that makes skating on ice possible. The better the process of water film formation, the faster the ice hockey player can go. Therefore, the aim is for the blade to reach a high temperature quickly and for the
temperature to remain constant, if possible.

The good thermal conductivity of metals, shared by the solid steel blades used in conventional systems, has the effect of rapidly dissipating the frictional heat generated. The requirements of the material selected for development of the new skate blade were specified to combat this effect.

The quest for a suitable plastic began with a definition of the way the system would function and thus ran parallel to design and engineering development (Figure 2).

Figure 2. From the first sketch right through the final
CAD design, the designer allows no compromises.

A

The first draft sketch
serves as a basis for
discussion between the
designers and engineers.










B

The preliminary model,
made from rigid foam,
enables the customer
to visualize the designers'
ideas,three-dimensionally,
for the first time.












C

After design release
by the customer, the
designers, working with the
plastics technical experts,
perfect the design of the
skate system using CAD.











D

The CAD design data make it possible to construct a stereolithographic model, which is painted and used to test the entire system structure.

The extreme physical requirements the plastic is exposed to and the conditions imposed by production processes made this search the most time-consuming stage in this entire development project (Figure 3).

Figure 3. The detail modifications of the
individual component groups are influenced
by different plastics and additives and
directly implemented in the CAD design.

Particular problems were posed by the connection between the blade surface of the skate system ? a metal profile ? and the plastic.

When a suitable plastic had been found to withstand the physical stresses, different expansion and shrinkage coefficients of the plastic and metal profile both in moulding and demoulding caused a defective connection between the plastic and metal. On the other hand, when this connection succeeded, then other properties such as the notched impact strength, inherent rigidity, and chemical resistance of the materials proved inadequate (Figure 4).

After numerous injection moulding trials, testing of prototype moulds, and skating trials, close cooperation between the plastic manufacturer, designer, and mouldmaker led to the selection of a material that met the specified requirements.

Figure 4. In a test at -41°C, an impact
corresponding to that of a puck traveling at
a speed of 150 km/h destroyed the skate base
made from an unsuitable material.

An injection mouldable, high-impact polyamide with 35 percent glass-fiber reinforcement stood up to the extreme stresses that occur in an ice hockey match. This plastic serves as the base material for the entire skate system and also for the blade itself.

The blade, i.e., the actual runner surface of the system, consists of a .7-mm-thick, high-strength metal profile. This metal profile, consisting of a spring-hard metal alloy, is laser-welded in a fully automated process to a second metal band provided with apertures, and is then permanently joined to the plastic during the injection moulding process.

The result is a blade which, because of the insulating effect of the plastic, does not dissipate the generated frictional heat so rapidly. The resulting heat buildup increases the temperature of the blade surface by about 3°C compared with conventional blades. As a consequence of this and the highly polished blade surface, the sliding action of the skate blade is improved by 40 percent. This, in turn, increases skating speed as compared with conventional skate blades.

Extreme Demands: Design

The practical implementation of the design for the basic skate and provision of laterally integrated stabilizers for the skate blade proved a further challenge. The physical demands made on these components were virtually identical to those made on the blade. However, this time it was not necessary to account for expansion and shrinkage coefficients as was the case with the plastic/metal composite forming the blade. One design objective was to reduce the weight of the skate system and yet still meet the high requirements of competitive sport. The skate blade developed from the polyamide/metal composite is 140g lighter than traditional skate blades and at present the lightest blade system.

This weight minimization was only made possible by the use of plastics in conjunction with a carefully thought-out design. The reduction in wall thickness required for weight minimization called for a design capable of withstanding the very different force effects. Lightweight structures found in nature and the laws of force distribution used in architecture served as the basis for the design. Thus, it was possible to reduce the wall thickness of the largest part of the basic skate to only 1.5 mm. The inherent rigidity of the system is retained, even if the player is a heavyweight. The skate blade resists compressive forces of up to 3,000N, such as act on the system when the skate is braked, for example, and also the impact forces exerted by the puck traveling at speeds of up to 150 km/hour, even at extremely low temperatures down to ?35°C.


Figure 5. The initial mouldings of the skate
base, stabilizers and blade from prototype
moulds are used for material loading tests
in the laboratory and on the ice.

To find the correct material, numerous injection moulding trials in prototype moulds and tests under practical conditions were required. This enabled resolution of problems relating to the flow behaviour of the plastics, such as sink marks in areas of high material accumulation and difficulties with fit in the individual component groups. By reducing the fiber content, it was possible to adapt notched impact strength at minus temperatures to the required torsional rigidity of the basic skate.

Adaptable and Interchangeable

Time-consuming blade grinding, required with traditional steel blades, is unnecessary with the skate blade in the plastic/metal system. The service life of this blade is three times longer than that of conventional systems because of the special metal alloy and the high surface hardening. Postgrinding of the blades costs more than purchasing a new blade and replacing the old one, which is taken back in the worn condition by the manufacturer and reground.

The skate blade can be changed by the player in a few seconds without taking off the skate. The stabilizers at the sides can be removed by undoing special screws and the blade changed. It is also possible to use different blades for varying player requirements. For this purpose, the injection mould has interchangeable inserts that make it possible to provide different radial curves on the blade surface in order to meet different player requirements.

The close tolerances between the individual component groups (blade, stabilizers, and base ? Figure 5) favour the force line paths within the system. The inherent rigidity achieved is greater than with any other skate blade. Colour variations in the system are possible by changing the pigment, as is surface decoration with special-effect paints.

Contact Information: frogdesign GmbH Mr. Hartmut Esslinger Grenzweg 33 D-72213 Altensteig Germany Phone: (49) 7453-2740 Fax: (49) 7453-27436
frogdesign inc. 1327 Chesapeake Terrace Sunnyvale, CA 94089, USA Phone: (1) 408-734-5800 Fax: (1) 408-734-5801

Rubbermaid slashes development time using CAE

Ever wonder how much abuse plastic household products can take before they're ready for recycling? Rubbermaid's ability to optimize new plastic product designs, such as hardware items, ensures that consumers rarely have to find out.

Earlier in its manufacturing history, Rubbermaid distinguished itself by molding trash cans able to withstand the "freeze-and-drop" test using traditional design analysis processes. That experience helped form the company philosophy. According to John Vura, CAD manager of the Home Products Div., Rubbermaid is committed to CAE to develop cost effective products that have increasingly shorter time-to-market cycles.

Vura's division recently installed Pro/E (from Parametric Technology Corp., Waltham, MA) as its CAD tool and Ansys (Houston, PA) as its preferred design analysis and optimization solution. Home Products' cadre of engineers and designers also relies heavily on flow analysis to determine potential warpage and cooling problems, among others. Even before these developments, however, the division's unique approach to product development already gained it marked improvement in certain new product lines, particularly plastic hardware items including toolboxes, mailboxes, modular shelving, and small-parts organizers. Of the various hardware items, the 20-inch, flat-top toolbox seems to have benefited most from design analysis and optimization.

Home Products' design team - consisting of industrial designers and product, mold, and design engineers - has been able to improve the reliability, structural integrity, and moldability of the toolbox by coupling the design optimization capabilities of Ansys with an in-house proprietary loads analysis package. The enhanced 20-inch, flat-top toolbox no longer incorporates steel hinge pins and it now has all-plastic hinges, thus resulting in a lighter product that is more corrosion resistant and less costly to produce.

Before implementing its CAD and CAE systems, the Home Products Div. relied solely on outside engineering consultants to perform design analysis, some of whom were using traditional design analysis techniques to develop design-for-manufacturing data. The Home Products Div. installed Ansys software to gain more control over costs associated with the design development process, to bring down total product costs. Using Ansys, engineers and designers can simulate and optimize designs early, allowing time for other departments' input prior to production. Engineers in the Wooster, OH-based division simulate how real-world testing affects a product's stability, applying operating loads and other criteria to study physical responses, such as weight, stress, strain, and pressure.

Simulating analysis up-front in the development process has significantly streamlined new product design costs. Vura says, "We eliminated trial-and-error methodology from our design processes. Our 20-inch toolbox is one example. We now have analysis tools that allow us to accurately simulate at a moment's notice how a product will perform under stress; we can perform thousands of simulated handle lift tests with a 25-lb weight inside the toolbox prior to running the actual tests. Thanks to engineering expertise supported by today's technology, we're able to deliver better customer satisfaction and we have reduced new product development time by a large percent."

More basic plastic items, such as food containers, sinkware, and trash cans, once made up the vast majority of Rubbermaid home products. These did not warrant structural and optimizational analysis - structural demands are much less stringent for these parts. However, as the division continues to introduce more structurally complex products, such as plastic hardware items, analysis is becoming essential. According to Vura, "The functional nature of these items warrants a whole new set of design standards. You're not going to encounter too many structural issues with items such as wastebaskets and food containers. But when it comes to portable work centers and shelving, there is a different set of industry standards to consider, especially where weight, stress, strain, and compression deflection are involved."

Deploying analysis up-front in the development process has proven beneficial in leveraging new product marketability against profit margins as well. "If one of our retail suppliers wants us to design a product at a certain price, there's always a chance that we can't achieve it because of the overhead involved in its construction," Vura said. "Through analysis simulation, we're able to evaluate immediately whether we can, in fact, meet the request, and how to do it and get a good return on our investment. That's how a company such as Rubbermaid succeeds in a global marketplace."

Vura admits that although Home Products has made significant strides with its new analysis and optimization tools, its expertise in using and fully understanding simulation and optimization possibilities continues to evolve. Though Ansys has been applied primarily to analyze structural designs, Home Products also uses it to simulate other aspects of production, including the optimizing of shipping cartons. Says Vura, "We can simulate shipping a certain number of wastebaskets or laundry baskets to prevent products and packaging from arriving in less than optimum condition."

By Design: The competitive edge


In this bimonthly column, Glenn Beall of Glenn Beall Plastics Ltd., Libertyville, IL, shares his special perspective on issues important to design engineers and the molding industry.

The custom injection molding business is prospering, but there are dark clouds on the horizon.

More and more original equipment manufacturers (OEMs) are learning how to reduce their costs by buying offshore. One OEM now purchases more than 1.2 billion molded parts in China. U.S. material manufacturers and processors are opening facilities in Mexico, South America, and Asia. Foreign processors are establishing huge plants in this country. Some of these operations are justified by the multinational transportation industry's desire to reduce its global supplier base. History indicates that the other OEMs will follow the example set by the car companies. These transplanted processing facilities will look for nonautomotive work once they saturate that market, lose a contract, or experience a recession. At a steady rate, injection molding companies are being auctioned off, bought out, or merged into larger multiservice organizations.

Unrealistic Expectations

Simultaneously, there has been what many people believe is an unrealistic increase in customer expectations. Every single project is now expected to be at the lowest possible cost, the highest possible quality, in the shortest possible time - and with a smile. The old "as soon as possible" phrase, which used to be reserved for special situations, has now become standard operating procedure. What do we use now for special situations?

Competition for the remaining domestic market is fierce. Molders find themselves selling in a buyer's market. Customer expectations and competition will continue to increase. No intelligent person expects to return to the good old days, when doing business for a profit was fun.

Survival of the Fittest

How are custom molders to survive if profit margins continue to decline and competition becomes more intense? Competition will increase, and the best of the custom molders will prosper. In the final analysis, all injection molders do the same thing. They mold parts to a level of delivery, quality, and cost that someone is willing to pay for. All molders may do the same things, but there is a big difference in the way they do them.

As molders search for ways to survive in a global economy, they should consider that the parts they mold are always made up of four basic elements: the design of the part, the material, the tooling, and the molding. (See 'The four elements of a successful product," February 1997 IMM, p. 44.) There are many other things that are required to produce a molded part, but these four elements will always be present.

The Constants

Normally, all of the competitors receive the same design or part drawing when they are invited to submit a proposal.
  • Material. When an OEM specifies a designated plastic, the material becomes a constant for all competitors. If a material is not specified, all molders can select and buy the same material on the open market. One molder may strike a better deal with a resin or pigment supplier. Another may buy in larger quantities. An enterprising competitor might have the material specially compounded to improve its moldability, or to incorporate a less costly filler or recycled material. These options and others are, however, available to everyone who is competing for the business. The material is, or can be, a constant.
  • Tooling.Each custom molder has his own approach to tooling. Some have captive tool building operations. With a few exceptions, those same tooling capabilities are available in the open market. Some molders purchase only foreign-built molds. Others favor large cavitation. Some strive for efficient molding by investing more in the tool - positive part ejection and extra cooling, for example. Others settle for a higher part cost as they strive for the lowest tooling cost.

    All competitors can, however, specify the same tooling features and purchase their tooling from the same moldmakers. Tooling is, or at least can be, another constant.

  • Molding. There are many types and ages of injection molding machines in use today. A new molding machine is normally better than an old machine, but not all parts have to be produced on a new, high-tech machine. Some machines perform some functions better, or more consistently, than others. In simplistic terms, injection molding machines do only two things. They melt and move plastic material from one place to another, and they open and close a mold. All injection molding machines perform these same functions. All of these different kinds of machines are available on the open market. All of the molders who are competing for the same business can use the same kind of machines if they so choose. It isn't the molding machines, but how the molder uses that machine, that is the qualifying factor.

    Some processors do a better job of molding than others. The differences among molders are primarily the result of the company's management philosophy and the accumulated knowledge of its staff. There is, however, nothing that prevents any molder from training and upgrading his staff. All custom molders can hire a processing engineer from Ferris State or Lowell. In the final analysis, all competing custom injection molders can acquire the same molding equipment and staff.

The Variable

Design, however, is unique. Each part design is different. Part design is normally specified by the customer and it is outside of the molder's control. If all competing molders quote the same part drawing, the design is also a constant. But it doesn't have to be that way.

Today, OEMs are more open to suggestions for efficiency-improving design changes than at any time in the past 30 years. OEMs have come to realize that their designs have to be improved in order for them to prosper in a global economy. The best way for a molder to help his customer and himself design parts that are properly proportioned for economical tooling and molding is by ESI, or early supplier involvement.

If the molder is involved with his customer's design team early in the project, the part drawings can be done right the first time. This is better than making last-minute design recommendations after the drawings are finalized and the designer is assigned to another project. Early supplier involvement is the best, but the next best approach is to fine tune the design at the time the project is being quoted.

Overcoming Resistance to Change

OEM designers dread having their designs changed late in a project. Buyers want all suppliers to quote the same way for easy comparison. One proven way of overcoming this resistance to change is to submit a two-part quote. The first part is based on the drawing as received. The second part, with a lower piece part and/or tooling cost, is based on an improved design.

There are greedy OEMs who cannot resist the temptation of requoting the improved design with other molders. It only takes one or two projects to determine an OEM's style. If this happens, the molder has only lost some time in determining that the OEM is unethical. Thereafter, he treats the OEM in the standard adversarial way, where each party is expected to take advantage of the other if given a chance.

The Competitive Edge

If all molders receive the same drawing to quote, most will simply quote the part as drawn, according to the tried and proven principle of giving the customer what he asked for. The enterprising molder, looking for a competitive edge, could recognize this as an opportunity. He could search for ways to improve the design and his ability to compete.

For example, will providing draft angle on the side cored surfaces shorten cycle time? Can the addition of radiuses and a slightly thicker wall allow the use of a weaker, lower cost material? Would a slight design change allow the threads to be located on a parting line to reduce tooling cost and the cycle time required for an unscrewing mold? If the molder taking this approach is successful in making the new part more efficient to produce, he will have a competitive edge over the molders who took the easy approach and quoted the part as drawn.

The material, tooling, and molding elements of an injection molded part are usually constants for everyone competing for the business. Today, it is unfortunate (but true) that there are many improperly designed parts being released for production. One good place to look for a competitive edge is in improving the design of these parts. Any molder who starts with a better part design than his competitors will enhance his chances of future survival and prosperity.

Productivity

Suwandi Dhanu, general manager, believes
that among his employees, a willingness to work
is as important as an ability to work.

Back in the late 1970s, Fuji Photo Film Co. Ltd. was a small company. In 1979, Otje Honoris (1922-1981) started a small company of his own in Jakarta, as Fuji's sales agent. Fuji saw a tremendous opportunity for growth in Indonesia, the Southeast Asian marketplace, and around the world, but was faced with high import duties for manufacturing its products in Japan and exporting them overseas. The import duties were in the neighbourhood of 30 percent in Indonesia alone. Such duties would be only around 5 percent if Fuji manufactured in Indonesia.

Fortunately, Honoris had experience in injection moulding. He worked for nine years with a multinational captive moulding operation. No one else in his company knew moulding. Still, a unique cooperative relationship was formed. Honoris began moulding film spools for Fuji in a small plant with 79 employees and four moulding machines.

His company, known today as PT Honoris Industry, became independent in 1982 and manufactured Fuji's first camera, the M-1. Today, Fuji's market share is around 85 percent, just in Southeast Asia. Today, Honoris' company does 100 percent of Fuji's precision custom moulding and contract manufacturing in two plants in Indonesia totaling 70,000 sq m, with 2,600 employees and 56 moulding machines.


Pt Honoris must hold and maintain moulds for
its major customer for seven years after the
introduction of a new product. It presently has
540 active moulds.

There are more than 60 plastic components in a single Fuji camera. The company presently manufactures nine camera models involving 540 active moulds. Three years ago, PT Honoris Industry branched out into new markets with new customersÑmaking car stereos for Japan's Pioneer. The company oversees a very large number of employees, running several very sophisticated pieces of equipment, yet ships millions of parts, just-in-time, that exceed customer quality expectations. How? You may be as surprised as Fuji originally was when you find out. Join us on our tour of the PT Honoris Industry in Ciawi, West Java.

A One-stop Shop

About two hours north of Jakarta in the Bogor, Jawa Barat area, the Ciawi factory is found up a winding mountain road behind an impressive gate with uniformed guards that salute you as you drive through.

All 56 moulding machines at the Ciawi Factory
are automated and operate in a well-lit,
climate-controlled environment.

The factory grounds look and feel like a small university campus. Before touring the manufacturing areas, you must exchange your shoes for slippers and put on cleanroom garments. The manufacturing environment is tightly controlled for quality's sake and steady-state machine performance, and production is monitored and controlled by computers.

The first thing that comes to mind when you enter the moulding area is, "Where is everyone?" Then you notice the parts-removal robots on every machine, the centralized materials handling system, and the parts conveyors. PT Honoris Industry is highly automated. Every machine is equipped with either a Harmo pneumatic parts-removal robot or a Harmo sprue picker. Materials handling systems and dryers are from TEW and Matsui. Also, the company has designed and built its own automation peripherals. Standardization is a company policy. Resins primarily are from Japanese suppliers, such as Toray, Mitsubishi, and Teijin.

The area in which camera bodies, camera components, and other parts are moulded is well-lit, air-conditioned, and immaculate. Thirty Nissei machines are arranged perpendicular to the wall with injection units facing the aisle. Robots remove the parts and place them on inclined conveyors feeding QC inspection and packaging stations. Typically, production can involve some six mould changes per day.


Optical inspection of moulded lenses takes place
right on the factory floor. All parts in the plant
receive a daily visual inspection, random daily
check for photoresolution, and monthly
reliability tests.

This room with its larger machines is impressive, but PT Honoris Industry's lens moulding room is state of the art. Here, top-of-the-line Sumi-tomo presses are used. Machine utilities and materials handling tubes are overhead. Though the machines are arranged in the same orientation as in the other rooms, there are differences.On some lines, the company has installed intravenous-like bags, the sort you might find in an operating room, to ensure that even the surfaces of the conveyors are kept clean with regular drops of water.Optical inspection systems with visual aids are on the floor of the moulding area to make absolutely certain all lenses moulded are to within specification.

So, where are all the people? Injection moulding is only one of four divisions at the Ciawi factory. Its optical division is equipped with curve generating, polishing, measuring, coating, and assembling stations for glass lens manufacturing. Its electronics division for cameras and car stereos is equipped with the latest chip mounting, wave soldering, and calibration systems, and has solder paste printing, inspection, and manual assembly teams. However, the majority of its work force is in its camera assembly division.

QCDSM

Credit for success has to go to the company's management style, described with an acronym: QCDSM. This stands for quality, cost, delivery, safety, and morale.

PMMA camera lenses (above) with .5 to .3 pitch
are moulded at reject rates well under 1 percent.
These camera bodies below are moulded to
within ±30 µm.

Regarding quality, the company says, "We are strict to customer specifications." Yet customers often are surprised to get more than what they were expecting. Lenses with pitches ranging from .5 to .3 mm are moulded, perfectly. In general, part tolerances throughout the factory are maintained to within ±30 mm. "Fuji asked for a standard reject passing rate of 98 percent. We achieved 99.2 percent," the company says.

Indonesia enjoys an attractive economic profile as a low-cost area of the global marketplace. Labour costs are relatively low ? minimum wage is about 165 rupiahs/month (US$ 3.00/day). But PT Honoris Industry puts more faith in continuous productivity improvement as a more reliable means of controlling cost. The company lives by this phrase: Good is no good, if better is expected. "We have formal programs in place that we've put together with our ISO and Kaizen teams to control our costs."

Production control and low-reject moulding help PT Honoris Industry meet its customers' just-in-time delivery schedules. "We maintain zero inventory of finished product. Our inventory is only in parts," the company maintains. And regarding safety: "We care. We have a very low accident rate." It also cares about the morale of its most precious resource, and the real key to its success ? its workers. The results are impressive. With 2,600 employees, employee turnover is less than 1 percent.

"In 1989, we realized that the company would be experiencing very rapid growth," says Suwandi Dhanu. "Our technically trained engineers were well prepared, but the assembly line workers, that was different. If you have 300 operators, you have 300 different characters. You have to standardize, you have to minimize differences to make a production line work," he explains. PT Honoris Industry sees to it that new employees learn more than the technical aspects of their jobs. Employees are taught good work habits and good work ethics through incentives, and through an enlightened management style. He believes that a willingness to work is as important as an ability to work.


Most PT Honoris employees work in assembly.
With 2,600 employees, turnover is less than
1 percent.

"We always say, as managers, an employee is not the inferior ? an employee is like a younger brother or sister. We all are very close to our operation. We work very hard to instill positive thinking among all the employees, and to eliminate blaming." It works. "Their mothers and fathers have come in and have asked, 'How did you do this?' They bring the good work habits they learn here back home, and everyone sees the results."

PT Honoris Industry has plans for expansion in Indonesia. It also plans to work hard to maintain its unique working relationship with Fuji, while striking new partnerships with new customers. Through partnerships with its employees, the company feels it can continuously improve productivity while continuing to surprise everyone with its success.

How A Korean Moulder Becomes A British Moulder

Within the past five years, dozens of Japanese and Korean OEM companies have set up manufacturing plants in England to supply automobiles, computers, appliances, and more to the European market. Many have been drawn to Northeast England by government-sponsored incentives designed to revitalize a regional economy suffering from a decline in coal mining and ship building. Korean electronics marketer Samsung, for example, has a sizable and growing production facility in Wynyard. Where, you might ask, does this good news for the British economy leave the company's previous suppliers?

Automation is a key to keeping production
lines running, as all Dong Shin machines
deposit parts onto a single conveyor.
At each machine, an operator adds value
by performing a secondary operation.



K.J. Park had been a successful supplier of injection moulded parts to Samsung in Korea for many years. Instead of seeing a loss when Samsung began production in England, Park saw an opportunity and went to England to learn first-hand what was possible. He then returned to Korea and, with four other injection moulding veterans, formed Woo One UK Ltd. to mould housings, bezels, and other parts for Samsung's British-made computer monitors. In the true entrepreneurial spirit, he wanted to begin production immediately...halfway around the world...in a different social and business culture...in the midst of the European Community's CE regulations.

Local Support and Know-how

To help Park in such matters as site location and staffing, the Northern Development Group, supported by the British Department of Trade and Industry among others, formed a group of specialists from industry and local and regional government to expedite the project. They quickly found an idle manufacturing building in Hartlepool that only needed some floor reinforcement to support the weight of moulding machines, and preliminary plans were drawn.

The building previously contained two businesses. An opening was made in the dividing wall so one section could be used for manufacturing and the other for warehousing raw material and finished goods. Woo One's start-up plan called for eight injection machines, reclaim of all production scrap, and automated handling of raw material and mouldings.

For injection machines, Park turned to a familiar name, Korean manufacturer Dong Shin, and that gave him access to the local know-how of General Plastics, which markets Dong Shin machines in the United Kingdom.

General Plastics completes the assembly of the Korean-built machines to conform with local electrical specifications and the safety and other requirements for the European Community's essential ? that is, you cannot operate a machine without it ? CE mark. However, even if you have a CE label on a machine, CE regulations may prevent you from starting it.


Raw materials and finished parts both
benefit from the latest in automated
handling system. A day's worth of ABS
comes from silos outside and is fed directly
to the machine hoppers.

Single-supplier Automation and Auxiliaries

With his operating plan in hand, Park wanted the minimum number of suppliers in the plant to simplify management. For example, he wanted one supplier for all the plant's automation: material handling, machine robots, conveyor lines. He also wanted that supplier to provide mould temperature controls, grinders, hoppers ? in short, all auxiliary and ancillary equipment. Several companies submitted proposals, and local know-how again figured strongly in the outcome.

Conair Europe's proposal to supply a £300,000 (US$ 500,000) package of systems was accepted just two weeks after Conair received the lead. Conair's central vacuum loading system moves incoming ABS into one of three 2.5- ton silos, each sized for an 8-hour shift. One ABS grade is loaded into a separate 1-ton bin. From a central drying station, material moves to six of the injection machines by vacuum system. The two smallest machines (50 tons) have single-phase vacuum loaders. Robots move mouldings from the large machines onto a conveyor system going to the warehouse. Some parts require assembly and/or pad printing.


Although most of the parts are large,
two small machines (one is visible at
lower left of the photograph)
also contribute.

Moulds are cooled by an externally mounted chiller and a Conair air blast system cools the hydraulic oil. In low ambient conditions, the air blast cooler can also handle the moulds, allowing the chiller to be turned off for energy savings. Woo One chose the air blast cooler based on a combination of economics and Conair's knowledge of British health and safety regulations. The air blast, unlike evaporative tower coolers, is a closed circuit. In England, open systems have been subject to inspection by authorities since the discovery of how legionella bacteria can be transmitted by evaporating water. The capital cost of the closed system was higher, but payback came in six months, and there are no health inspections nor ongoing expenses for water replacement and treatment.

Solving Problems in Advance

Park began looking for a site in July 1995. Early the following February, Woo One began bringing its machines online, following operator training by the British Polymer Training Association. By June it was in full production: six General Plastics/Dong Shin machines ranging from 150 to 850 tons with robots and Barber-Colman closed loop controls; two 50-ton Arburgs without robots for moulding smaller parts; automated raw material and finished parts handling systems; and CE labels on everything.

We mentioned that sometimes a machine with a CE label still cannot be operated. Although many European manufacturers now supply their products with CE labels already in place, if you add a robot with a CE label to an injection machine with a CE label, you create a "system." The system needs CE certification before use. Knowing that, Woo One made arrangements with Longlands College in nearby Middlesbrough to inspect the assembled systems and affix the CE label.

Woo One now runs seven days a week using four production teams. Each team consists of eight production specialists, one technician, and a quality control person. A day is divided into two 12-hour shifts with changeovers at 0600H and 1800H. A team works four day shifts, has four days off, then works four night shifts followed by another four days off. Including warehousing personnel and management, Woo One currently has 51 employees. To handle growth, there is a plan for the warehouse part of the structure to be converted to manufacturing and warehousing to be shifted to a new location.

Contact Information: Woo One UK Ltd. Mr. Keith Boynton, Manager, Human Resources Unit B, Sovereign Park Brenda Road Hartlepool, TS25 1NN England Phone: (44) 1429 867744 Fax: (44) 1429 862170

General Plastics Mr. Ian Hamer, Managing Director 319 Vale Enterprise Park Hays Road, Sully South Glamorgan CF6 5SY England Phone: (44) 1446 700537 Fax: (44) 1446 740841

Conair Europe Ltd., Mr. John Smith, Business Manager, Materials Handling Riverside Way Uxbridge, Middlesex, UB8 2YF England Phone: (44) 1895 258181 Fax. (44) 1895 850016

Succeeding as a Contract Manufacturer

Change is nothing new at SPM/Houston. In fact, the SPM family of companies has undergone several changes during the past two years, including becoming a division of the Dynacast Co., a worldwide manufacturing subsidiary that is part of the Coats Viyella global conglomerate. So the decision to open its Houston molding operation in 1994 wasn't difficult. The deciding factor in selecting that site was the company's ties as a supplier to Compaq Computer Corp.

Its relationship with the computer giant has been strengthened by SPM/Houston's willingness to be more than a molder by providing comprehensive manufacturing solutions to its clients at competitive pricing. That business philosophy resulted in SPM/Houston being awarded a contract to build Compaq's Presario 3020 personal computer - beating out even Asian competition - and becoming the first injection molded components supplier worldwide to receive such a contract from Compaq.

The contract represents the largest program ever undertaken by SPM or Dynacast. SPM/Houston molds the more than 15 plastic components that make up the Presario 3020 PC. However, the plastic makes up only 8 to 10 percent of the unit's wholesale selling price to Compaq. Today, SPM/Houston has a new attitude and way of doing business that raised the company from the ranks of "just a molder" to that of a contract manufacturer.

Considering that molding is just a small part of this plant's activities, let's take a look at some of the manufacturing challenges. Then we'll learn what's behind this decision strategically.

Plant Layout

One critical factor in being a contract manufacturer is plant layout. Press placement in relation to production requirements increases overall production efficiency. In one case, as the requirement for one part ramped up to the point that two molds were required, a conveyor was placed between the two presses molding the part. Robots remove the parts in sequence, placing them on the conveyor where one operator can handle the flow of production from both presses. "It's all part of being creative in how to do things to make the total operation more efficient and cost effective," says Gary Ahlschlager, Compaq account manager for SPM/Houston. "When you're a contract manufacturer, production becomes more than just molding parts and putting them in a box." Plant general manager Ken Jones says that what you see at SPM/Houston today is typical of a molder of the 21st century. "Compaq predicted in 1988 and 1989 that the vendor of the future would be what we represent to OEMs as a supplier," says Jones. "Its vision has become a reality at this facility." Today, SPM/Houston operates 19 injection molding presses, including two new presses from Van Dorn, with clamping forces ranging from 15 tons to 720 tons.

Plantwide organization is also important. "Being a contract manufacturer, as opposed to being just a custom molder, means you're buying more than just gaylords of resin," says Ross Whitman, purchasing manager for SPM/Houston. Prior to the start of production of the Presario project in August 1996, the company worked closely with Compaq to establish inventory control procedures and implement a barcode system to address traceability issues for the more than 50 component parts from more than 20 vendors worldwide that go into each Presario unit.

Because many of Compaq's electronic components suppliers are located in other parts of the world, lead times became a crucial issue and a logistical challenge for SPM/ Houston, which is responsible for purchasing all the components required to build the computer. That's where a good material requirements planning system comes into play. Too many high-dollar parts in inventory strap SPM/Houston's cash flow, and too few components mean computers don't ship on time. It's a delicate balance that the company has learned to aptly juggle through innovative new management systems and procedures.

Several assembly operations such as decorating and some subassembly work take place at the press. Subassembly work involves such operations as hot stamping, pad printing and sonic welding, and parts or subassemblies move from the press where that particular operation takes place to the assembly line where build-out of the units takes place. The subassembly is performed by an operator who is cross-trained in the main assembly functions. Those subassemblies are then sent to the line for final assembly and test. Most of the assembly is done by hand using small, electric hand tools, which means that managing the flow of work and the people who do that work is also crucial to an efficient manufacturing operation. Compaq engineers assisted SPM/Houston with the design and layout of the assembly line, including the fixtures that hold the parts in place while workers assemble the various pieces.

SPM/Houston is also responsible for the quality of the completed computers, which meant designing testing methods. For example, Mark Cox, SPM/Houston's quality assurance manager, collaborated with Compaq's vendor for power supplies in developing a test fixture that tests each power supply to 100 percent burn-in prior to going to the line for assembly. At the end of the assembly line, each built-out computer undergoes a 19-step, computerized testing process to ensure that all of the computer's components work properly.

On the Road to Contract Manufacturing

Becoming a contract manufacturer isn't easy. It requires a strong financial base to shoulder the costs involved in ramping up an assembly line, expanding internal functions, and implementing new management procedures, particularly in the areas of purchasing and inventory control. Fortunately, through its parent companies, SPM/Houston has that financial base. SPM currently has operations in the United States, Canada, Mexico, and a new facility in Wales that opened in January. The company continues to seek new opportunities for opening new facilities in other parts of the world as customer demand dictates.

"The level of commitment by the molder who takes on the entire project is much higher because he has no one to blame," says Ken Pulliam, project/production manager, adding that, because all the pieces to the puzzle are in one house, all the problem solving is done in one place, eliminating finger pointing by the various suppliers if something goes wrong.

By the same token, adds Whitman, "a true partnership means that if something does go wrong at the contract manufacturer's, the OEM takes some of the responsibility."

Fred Smith, regional manager of business development adds that the partnership formed between SPM/Houston and Compaq over the past several years is not typical of the industry, primarily because generally there's still a lot of mistrust when it comes to revealing financials and manufacturing cost structures. "It's actually a process of bringing the two companies together in such a way that the OEM's cost expectations are compatible with the contract manufacturer's profit expectations," he says. "It's a give and take project."

Once a partnership like that between SPM/Houston and Compaq is formed, the entire culture of the molder begins to change. "We're looking at ourselves as a global organization with the evolution of our business," says Smith. "We begin to see everything from a global perspective. When you start to develop that in your corporate culture, you get a different mind set; one that says you can be competitive with anyone."

Being a contract manufacturer also changes the perspective of the OEM community on what the role of the custom molder is in the overall production scheme. Jones adds: "OEMs have a certain mind set about what a molder is, and it's up to us to show them it's different." Additionally, Compaq introduced SPM/Houston to each of its suppliers and arranged meetings with each of its commodity managers to make sure that all the parties involved in the project stay on the same page throughout the life of the program. Cox qualified the vendors that would be supplying Compaq's components to SPM/Houston.

U.S. suppliers may have higher labor costs than suppliers overseas, which might be seen as a competitive disadvantage. However, SPM/Houston's management believes the company is proof that it can be overcome. "Labor may be cheaper in some foreign countries, but we still have the edge in technology in the United States," says Ahlschlager. "Instead of throwing labor at a challenging program, we figure out how we can utilize technology to increase our production efficiencies."

Now that SPM/Houston has successfully completed its entry into contract manufacturing, the company plans to offer its expertise to other companies requiring the same level of full-service production and assembly. Although molding remains an integral part of its manufacturing operations, molding plastic components has become a support function of SPM/Houston's assembly business rather than its primary business. Now that the assembly operation has ramped up to full speed, SPM/Houston plans to do similar work for other companies in the computer, business equipment, and telecommunications industries. It has already begun a similar program for Dell Computer Corp. on one of Dell's towers, and plans more for the future.

According to Tim W. Hayter, regional general manager for SPM/Dynacast, OEMs will continue to demand that their top suppliers go global with them. "I'm seeing a tremendous shift with OEMs as they get on this global march; they want their suppliers to go with them. Our job is to position ourselves to be able to respond to this. We know we can't be all things to all people, so we've chosen to transition from being a general supplier to becoming a strategic supplier in response to OEMs."

The possibilities that await molders who choose to move into the arena of being a contract manufacturer are endless, and it's the way the industry is moving. "Downsizing and heavy outsourcing by major OEMs plays right into the hands of molders if they learn to take advantage of it," says Smith.

SPM/HOUSTON, A dynacast Co., Houston, TX
Square footage: 65,000
Markets served: Computer, business equipment, and telecommunications
Annual resin usage: 1.5 million lb
Materials processed: PC, ABS, PVC, ABS/PC
No. of employees: 250 total; 60 percent permanent; 40 percent temporary
Shifts worked: Four shifts, seven days a week
Molding machines: 19 machines, 15 to 720 tons, Toshiba, Van Dorn, Boy
Secondary operations Decorating, hot stamping, sonic welding, pad printing, assembly
Internal moldmaking: Not at present, but planned
Quality: ISO 9002 in process

Employee Training

Being a contract manufacturer also requires employees with new skills and a different mind set than those of the typical custom injection molder whose primary employee is a press operator. Fred Smith, regional manager of business development for SPM/Houston, says that constructing a computer takes a completely new mind set from just molding parts for a computer. "We don't think like an injection molder anymore," says Smith. "We offer total manufacturing solutions to our customers, so we think more like an OEM."

Working hand-in-hand with Compaq, SPM/Houston set up training programs for its employees while the molds for the Presario were being built. Preproduction plastic parts and all the electronic components were laid out on the conference room table, then assembled by experienced Compaq personnel while SPM/Houston video-taped the process to use in training its assembly workers. Lead assembly personnel were hired, and 60 days later, after obtaining production parts, SPM/Houston made a more extensive training video.

Employees selected for the assembly line have specific skill levels, and all received training with help from Compaq engineers in two classes per week for each of the four shifts. It took SPM less than five weeks to get all four shifts ramped up to production speed - a total of 60 people on the line. "Support from the OEM is crucial to the total success of this effort," says Ken Pulliam, project/production manager for SPM/Houston. "We've been through many projects but the one thing that's made this one more successful was the way we worked together with Compaq."

Reject Rate Less Than .5 Percent for Optical Lenses and Systems

Figure 1. Altough E-Pin started out as a glass
lens maker, it has produced injection moulded
plastic lenses, coated and uncoated, since 1985.

The Taiwanese company E-Pin Optical Industry Co. Ltd. was founded in 1979 in Taipei and initially manufactured glass lenses and prisms for the camera industry. With the addition of injection moulding machines and a mouldmaking department in 1985, production of precision plastic lenses was initiated (Figure 1).

IMI visited the E-Pin production facility in Y-Ilan, Taiwan, to learn how the company succeeded in gaining such customers as Canon, Ricoh, Nikon, Minolta, Sony, Matsushita, Olympus, Philips, AT&T, Murata, Vision, and Minton from all branches of the optical industry and how, with 25 employees in Taipei and 115 employees in Y-Ilan, it manages to post annual sales of some US$ 10 million.

Research and development, along with stability and quality in the production process and strict testing of parts, are part of the management concept of Shan-Woei Shyu, the president and sole owner of E-Pin. Components with plastic lenses and prisms (Figure 2)

Figures 2 and 3. Today, E-Pin has broadened
its areas of expertise and is just as likely to
tackle precision lens specialties, such as printing
on lenses, both glass and plastic (above), and
complete assemblies (below).

account for most of the sales volume. Additional manufacturing steps such as coating of lenses, printing of lenses, and fabrication of components for the camera industry were continually requested by customers. Development of double lenses and the camera viewfinder forced E-Pin to start assembling components into complete units for its customers (Figure 3). Since 1989 E-Pin has designed and manufactured entire optical systems. "Actually, we are a systems supplier with in-house moulding," says Shyu. Besides lenses and prisms, the "heart" of the optical systems, E-Pin now moulds all necessary functional parts such as transport rollers, levers, snap connectors, frames, threaded bushings, and the housing itself. Only electronic circuits and metal components are supplied by outside vendors.

In addition to the plants in Taipei and Y-Ilan, E-Pin operates a joint venture with the Chinese government in Nanjing, China. In another factory in Chu-hai, China, lenses are coated under cleanroom conditions. "Injection moulding of lenses is not the strength of E-Pin today. Others can also do that. But combining injection moulding with subsequent processes such as printing of lenses, coating of lenses with silicon dioxide (SiO2), magnesium fluoride (MgF2) and aluminum, and fabrication of components for the camera industry - that's our strength," says Shyu.

In-house Manufacturing Cells

Each month, the company processes 13 metric tons of PMMA, 6 metric tons of PC, about 2 metric tons of PC/PS blend, 2 metric tons of 10 percent glass-filled ABS, and a few other plastics from Asahi, Nisseki, Teijin, and GE Plastics. Sprues and runners are sold to other injection moulding plants to be reground and blended. The extensive range of equipment for mouldmaking, glass lens manufacturing, and plastic lens processing totals 130 machines. Various coating lines, screen printing as well as pad printing machines, and an ultrasonic cleaning system are especially important for the plastic lenses.

All moulds are designed and built in-house. In one of the numerous production areas, which Shyu called typical, there are five injection moulding machines, two each from Fanuc with 30 and 50 tons of clamp force, respectively, and one from Arburg with 70 tons of clamp force. (Figure 4).

Figure 4. Lens production is accomplished
in a number of small cell-like clusters.

All together, E-Pin has 43 moulding machines from Arburg, Engel, Fanuc, and Sumitomo at the various production facilities, with clamp forces ranging from 30 to 150 tons. Six additional fully electric machines in the 200- to 300-ton range are to be added this year.

Mounted on each machine is a three-axis robot that removes parts from the mould and places them on a conveyor. At the end of the conveyor, parts are degated and presorted for assembly.

Initially, plastic lenses were moulded via injection-compression on fully hydraulic machines from Engel and Arburg. With the injection-compression technique, plastic is injected into a partially closed mould. Compression occurs only as the mould closes completely. This pressureless filling of the mould eliminates moulded-in stresses in the lenses. "We established quickly, however, that on fully electric machines, optical lenses could be injection moulded conventionally without moulded-in stresses," says Shyu. E-Pin regards several aspects of the Roboshot machines from Fanuc as especially beneficial when moulding precision parts:

  • Melt temperature can be controlled to within .1°C.
  • Screw position can be maintained to within .01 mm at every injection speed.
  • As a result, the shot volume is very exact.
  • The specified pressure profile can be executed with a maximum deviation of only 1 bar during injection.
  • The injection pressure is measured by a pressure sensor in front of the screw tip.
  • Setpoints and actual values can be viewed simultaneously.

Another advantage of the fully electric machines is that the various mechanical machine functions occur in parallel. Thus, the ejector pins can advance and break off the gate during mould opening.

Round-the-clock Reliability

Shyu explained that only three-shift production 24 hours a day makes non-stop production, low production costs, and high process stability possible.

Figure 5. The latest QC equipment is used
to meet the stingent quality standards
of customers.

The latest QC equipment helps to achieve complete quality control, which extends from incoming material through production to testing of finished parts (Figure 5). E-Pin guarantees its customers a defect rate of less than .5 percent for finished parts and is currently working on ISO 9001 certification.

To check refraction in the lenses and measure surface quality (roughness), E-Pin uses a total of six laser interferometers from Zygo, USA, and Olympus, Japan. A computer-aided spherometer (THRS, UK), a microscope (Nikon, Japan), and 3-D coordinate measuring machines determine the wavelength and geometry of the lenses. Four spectrophotometers (Shimasu and Hitachi, Japan) measure the intensity distribution of photographic spectra. Assembled components undergo a complete test at the end of the inspection line. Parts are then packed, driven by trucks to the nearest harbour, and finally shipped.

Contact Information: E-Pin Optical Industry Co. Ltd. Mr. Shan-Woei Shyu 4 Fl., No. 16-2, Sec. 2 Chung-Yang S. Rd. Peitou, Taipei, Taiwan, R.O.C. Phone: (886) 2 894 8691 Fax: (886) 2 891 1107

Fanuc Ltd. Oshino-Mura Yamanashi Prefecture 401-05 Japan Phone: (81) 555 84 5555 Fax: (81) 555 84 5512

A Global Automotive Supplier

MaP Operates a large modern injection moulding,
assembly, and finishing plant north of Lisbon
producing a variety of automotive interior
components to tight specifications.

It has become very clear that those injection moulders who want to be Tier One automotive parts makers in the next century have to pass some very stringent tests: they have to be absolutely first class in terms of technology and consistent quality; they have to be global suppliers in the truest sense of the word; and they have to offer enough R&D depth to be an active partner in the development of new parts.

Following the recommendation of Ford Motor, we found one such company in the center of Portugal ? MaP?Materias Plasticas SA of Leiria ? that already passes these tests and is poised for additional growth as a global supplier.

Moulding parts for automotive companies has become, particularly in recent years, one of the more demanding areas in plastics. Car makers have continuously toughened quality requirements and moulders had to deliver or stop being suppliers. Car makers also exerted major efforts in winnowing the list of suppliers to relatively few ? suppliers that can produce quality product on a sustained basis and, if possible, do so on a global and uniform basis. "To survive," said our host and director of marketing for Technical Products Nuno Queiroz Romero, "you need to have a global position."

One result of this evolution is moulders that remain tend to be plants where you find a concentration of often very advanced technology combined with an almost extreme attention to quality control.

Background

MaP was first formed in 1946 and engaged in the injection moulding of housewares and bathroom components. Many of these products were plated. Until 1975, the company was also engaged in numerous other processes including film and PVC profile extrusion. The expertise of plating parts as well as the precision moulding requirements of bathroom parts ? such as faucets ? allowed MaP to go after other business opportunities with similar precision requirements.

This was the company's primary business until 1975. At that time, it started to concentrate only on injection moulding of a wide range of housewares, bathroom fixtures, automotive, and electronics parts. This was quite a change: in one year the company eliminated 90 percent of its product line to concentrate just on one plastics production process.

In 1985, the company formed a Technical Products division that concentrated on automotive components, such as radio bezels, as well as technical products for customers such as IBM in France for whom MaP moulded structural foam parts. Other markets were housewares, furniture, various E/E parts, and industrial products.


The moulding floor is arranged in workcells,
each turning out components for a separate
product. The company operates all types and
sizes of moulding machines.

In 1991, the company started to design from the ground up a new injection moulding and finishing plant specifically designed for technical moulding. Inaugurated in 1993, this plant was designed with the specific quality control requirements of the automotive industry in mind, says Romero, who was involved in that complex process.

In 1996, the company split the bathroom business from the Technical Products business, realizing that these had become two entirely different companies. Finally, in 1996, the company made a strategic move towards becoming truly global by entering into a partnership with Key Plastics USA of Novi, Michigan, USA. That resulted in the name change to MaP/Key.

Rapid Growth

What marks MaP/Key more than any other factor is that the company's technical products business ? most of which goes into cars ? has grown very rapidly with growth rates typically found only in such high growth markets as software and Internet technologies.

From 1994 to 1995 ? with sales above US$ 6 million ? sales more than doubled to US$ 18 million. By the end of 1997, the company projects sales to again increase sharply to more than US$ 23 million.

Concentrating on a Few Customers

Key to the company's philosophy is that it can only remain a world? class supplier if it concentrates on relatively few customers. This, says Romero, allows it to build long? term relations and provide the incremental improvements in quality so desired by automotive customers. Today MaP/Key already supplies customers globally, shipping product to Brazil, Spain, and France. Over 60 percent of its output ? which first goes to a Ford assembly plant in Portugal ? is ultimately exported from Portugal. While technically a custom moulder, MaP/Key more resembles one of the high? quality Japanese moulding plants that dedicates its entire production to one or two customers and, in a sense, becomes part of that customer's operation. MaP/Key's goal is to grow with Ford of Europe, its primary customer. Today MaP/Key has five major customers. It aims to grow the business with each one.

This seemingly narrow yet very positive approach to a moulding business is also reflected in the limited number of products moulded, partially assembled, and painted in that plant. MaP/Key's Technical Products division currently produces radio bezels, instrument clusters, housings for electrical equipment, housings for telecommunication equipment, and cable ducts for wiring harness. Other parts are outside panels and screens for computers; front baffles and panels for loudspeakers; housings for electrical appliances ? such as coffee machines, grills, or hair dryers; and components for office furniture.


A large and fully automated warehouse keeps
track of resin supply ? limited in
accordance to just-in-time requirements
? completed parts, and extra moulds.

Virtually all of these are parts for which appearance is critical; many, such as the automotive parts, must be matched to other components. The company's 50 years of experience in moulding appearance parts, such as bathroom components, provides a rich knowledge base.

Automotive customers have made it perfectly clear in recent years that one price of being a supplier is that suppliers will foot part of the bill of designing and developing new parts. This requires MaP/Key to devote considerable resources on basic part design and engineering. Some 18 plastics and design engineers are devoted to this task.

The Plant

MaP/Key had the advantage of building a new plant from scratch just a few years ago. The plant was designed from the ground up to allow for flexible manufacturing and quick product changes. This is of particular importance when serving customers increasingly demanding just? in? time delivery, says Romero. "We ship to Ford every day." For finished product, the company's clients maintain an inventory of just 1.5 days.

MaP/Key operates 35 injection moulding machines ranging in size from 40 tons to 900 tons clamping force. Machine suppliers include Netstal and Engel for the smaller machines and Krauss? Maffei for the larger units. In addition, the company operates two twin? shot injection moulding machines. Virtually all injection machines above 500 tons clamping force are equipped with part? removal robots. Quick mould changers have been standard for several years.

The injection machines are arranged in production cells, all dedicated at a given point in time to making one or two specific products and all related components. The company also has one cleanroom for clear optical parts such as lenses for instrument clusters.

Materials, stored in a computerized warehouse, are brought to a central feeding and drying station and are vacuum? conveyed to the injection machines. MaP/Key uses engineering resins supplied mostly by GE Europe, BASF, and DSM.


Moulded parts are placed on trays and then moved
on those trays through subsequent painting, quality
control, and decorating stations before they are
assembled into the final product.

Quality Control Is Critical

For quality control, the company has a fully equipped laboratory. Parts can be subjected to dimensional quality control on two CMM computer controlled machines, or on a profile projector, and can be tested with various electronic gauges.

The lab and the production control offices next door are right next to the plant floor, visually connected through large open windows. Supervising process engineers can access key statistics and other data at any time and can monitor quality in "real time."


After painting, the bezels are dried and then
subjected again to quality control. Quality
control is conducted both visually and with
various measuring instruments

MaP/Key has full statistical quality control on several key process parameters in real time. Additionally, all injection machines are tied into central MRPI and MRPII processes, allowing for remote computer and process control.

This devotion to quality control is of great importance for the company's product line. All parts have to be moulded to very tight tolerances, often to less than ±.05 mm. Maintaining recommended moulding temperatures, keeping the materials supply free of any debris, and reducing other such factors as static are paramount for MaP/Key: probably 90 percent of the output is appearance parts.

While the company uses every known tool in terms of electronics for quality control, each part also undergoes several visual inspections. This reporter counted six different visual inspection steps for the various components that make up a radio bezel. All over the plant, you find large boards on which are mounted "perfect" parts as well as parts with a wide range of problems to assist workers in quickly spotting mistakes.

MaP/Key has impressive quality control ratings from its clients in addition to operating at ISO 9002.


Many of the final components are assembled
by robots. Inspection is done visually and some
final assembly steps are also done by hand.

Secondary Operations and Finishing

After being moulded, the parts are conveyed to a secondary finishing area. There, MaP/Key does lacquering, laser etching, robotic assemblies, and hot stamping. While much of these operations may appear routine, it is important to note that MaP/Key applies its expertise and developed many of these fully automated finishing systems on its own.

For painting operations, MaP/Key offers three separate systems: an automatic electrostatic paint line by high rotation bells and two booths for painting with conventional guns.


A fully automated paint line built into MaP's
specifications paints parts to the required
automotive finish.

Small parts ? in specially designed racks that accommodate several hundred items ? move automatically through the paint station. Large parts are hung on a conveyor belt and are moved through a painting line that offers conventional automatic and semiautomatic spray painting.

The company has specialized technology for laser etching, used to mark radio bezel parts with all types of graphic designs. For hot stamping, MaP/Key has machines up to 100 tons and can hot stamp parts as large as 400 mm in width or length. Other finishing operations include silk screening, pad printing, ultrasonic welding, and heat staking.

Radio bezels and other subassemblies are assembled in a fully automatic conveyor system equipped with numerous robots. The system is flexible and can be quickly changed to accommodate various part designs. Much of MaP/Key's proprietary and patented technology is used for this complex assembly process.

Research and Development

A substantial portion of MaP/Key's annual budget is devoted to research and development, aimed at developing improved production technologies. The company has a team of 18 engineers that also work on quality control and process monitoring. The company is closely involved in part design, using computer? aided part design, and works with various mouldmaking companies throughout the region.

At the core of the current R&D program is the development of new laser etching technologies of painted and nonpainted components, technologies for two? coat painting, heat staking, technology for structural foam parts for office and computer components, and enhanced manufacturing monitoring systems.

MaP/Key clearly benefits from Portugal's improving education system. According to Romero, the plant's 380 workers constitute an easily trained and very stable workforce. MaP/Key devotes substantial resources on training and further education for its workers. Another benefit ? hard to match anywhere else in the world ? is that the plant operates some 20 km from what must be considered the world's largest concentration of mouldmaking companies. More than 200 mouldmakers operate in the nearby Marinha Grande area.

MaP/Key's goal is to become even more global. This, says Romero, can ultimately only be done through partnerships and multiple manufacturing locations close to the final assembly plants. MaP/Key hopes to accomplish this through the partnership with Key Plastics. Key Plastics, in a similar business and with a similar philosophy as MaP/Key, recently purchased a minority share of MaP/Key. In April 1996, Key also acquired Clearplas Ltd., an automotive moulder in Coventry, England. That company, again in a similar business, now operates as Key UK.

In the United States, Key operates 10 moulding plants in Plymouth and Grand Rapids, Michigan; Felton and York, Pennsylvania; Hartford City, South Bend, and Hamilton, Indiana; and Montpelier, Ohio. The company also has a plant in Chihuahua, Mexico.

The "Green" Approach

Environmental protection is serious business for MaP/Key. Considerable resources are devoted to preventing pollution by fluid or gaseous by-products of the painting or moulding operations. Equipment is selected not only for production efficiency, but also for energy efficiency. All facilities are designed to maximize natural light. To minimize water usage, rain water is used in fixed circuits for applications such as cooling or cleaning.