Injection Molding:

Complete Guide To Scientific Molding

It’s not hard to understand how computing and innovation have positively impacted industries of all
types over the past 35 plus years. The injection molding industry is no exception. Plastic injection
molding nowadays is largely based on a scientific approach.

A scientific approach does not just involve new methods and the technologies that enable them. It
also touches upon every aspect of the injection process: planning, design, setup, material selection,
monitoring, optimizing, and all of the software, hardware, components, machines, and systems
involved. Also, highly-skilled and motivated personnel are essential to making it all work.

In the sections below, we’ll cover all aspects of scientific molding and how Rosti has become a
recognized industry leader. The content is designed to flow from a 30,000-foot view and on down to
more granular detail. Start at the top or click a section of interest below:

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Table of Contents
What is scientific molding? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

What’s the difference between traditional molding and scientific molding?. . . . . . . . . . . . . . . . . . . . . . . . . 4

Factors in science-based molding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Injection molding processing stages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Steps in the scientific molding process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Advantages of scientific molding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

The role of technology in scientific molding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

The role of mold flow simulation software in scientific molding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

The role of RJG in scientific molding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

How automation supports scientific molding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

What does it mean to operate lights-out?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

How does scientific molding benefit from specialized engineers and technicians. . . . . . . . . . . . . . . . . . . 11

What is decoupled II and decouple III molding?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Rosti engineers involved throughout entire process window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Where does design for manufacturing fit into the scientific molding process?. . . . . . . . . . . . . . . . . . . . . . 12

Why does material selection play such an integral role in scientific molding?. . . . . . . . . . . . . . . . . . . . . . 14

Calculating plastic residence time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

What attributes of scientific molding are used in part design and tool optimization?. . . . . . . . . . . . . . . . . 17

How do quality control resources impact scientific molding processes? . . . . . . . . . . . . . . . . . . . . . . . . . . 18

How has scientific molding transformed injection molding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Is it more costly to use an injection molder that implements scientific molding processes?. . . . . . . . . . . . 20

Why Rosti for your next scientific molding project?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

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 Injection Molding: Complete Guide To Scientific Molding

What is scientific molding?

Scientific molding is a process whereby the fill,
pack and hold stages are treated separately to
minimize fluctuations while improving overall
product consistency. Separating the stages is
also known as decoupled injection molding.
Molders who utilize scientific injection molding
equipment, software, and practices can,
according to scientific molding educator John
Bozzelli, “reduce cycle times, increase machine
efficiency, and ultimately make more money.”

What’s the difference between traditional molding and

scientific molding?
In the traditional method of injection molding, the mold is filled with a single shot under a constant
pressure to pack the cavity. In scientific molding, the cavity is filled to around 90-97-percent at a
certain velocity. In the next phase, the machine switches from speed control to pressure control,
where the cavity is filled or “packed out” to complete the process.

The scientific method allows for greater shot-to-shot consistency and improved control over the
specifications of the part. Conversely, large variations in part dimensions are often the case cycle-to-
cycle with the traditional method of injection molding.

A scientific injection molding approach is most essential in the production of complex parts and
components where even the smallest variation in molding variables can have a remarkable impact on
the process or finished product. That said, the goal of scientific injection molding incorporates two
key strategies:
• Develop a process that produces repeatable results with minimal variation
• Optimize dimensional or mechanical characteristics of a molded part

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 Injection Molding: Complete Guide To Scientific Molding

Factors in science-based molding

Another aspect of the traditional molding
process has to do with machine-based control.
It was believed there were 20 or more machine-
based settings that could affect various problems
with the molded product (dimensions, voids,
warp, and other quality issues). The research
sought to find parallels between problems with
the parts with the settings of the machine.

Over the course of many years, when it

was found machine settings had little or no
correlation to part quality, research shifted
from the traditional, machine-control method
to a science-based approach. The “plastics point
of view” became the revolutionary angle of
approach, having developed a plastics research
modern research based on the laws of science
laboratory at General Motors Institute in the
instead of the settings of injection machines.
mid-to-late 1960s.
Donald C. Paulson pioneered this scientific

Injection molding processing stages

Mr. Paulson focused on the four injection molding plastic processing stages best known to
control the properties of the molded part: heat, pressure, flow, and cooling. Each of these, Paulson
hypothesized, “Would be governed by the laws of physics. First, the Laws of Heat Transfer; second,
the Poiseuille fluid flow law; and third, the Equation of State for Plastic.”

Measuring and recording the machine and plastic variations for each of the four cycles over the course of
four years led Paulson and his team of researchers to make a couple of industry-changing conclusions:
• Physical laws other materials follow also apply to plastic processing
• The four plastic variables determine the characteristics and properties of molded parts
The scientific approach to molding doesn’t change the molder’s need to understand machine setup or
how the controls of a machine are used to impact plastic output and part quality. However, it does
help the molder make better decisions on what the control settings and cycle times should be, along
with solving part issues if and when they occur.

Heat Pressure Flow Cooling

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 Injection Molding: Complete Guide To Scientific Molding

Steps in the scientific molding process

As noted earlier, scientific molding involves a
decoupling of each of the three vital steps in the
process. Equipment and software measurement
tools are used in each cycle to evaluate and
ultimately help control the variables in the mold.
This is a systematic and real-time scientific
process where the physical laws that apply to
plastics are precisely controlled with respect
to heat, pressure, flow, and cooling under the
watchful eye of specialty-trained engineers.
• Initial shot. The cavity is filled to
about 98% of its capacity with velocity
(speed) control
• Fill and pack. The remainder of the cavity
is filled, and the cavity is compressed or
“packed out” under constant pressure
(pressure control) These decoupled steps in the scientific molding
process are said to “allow better control of part
• Cool and stabilize. The part cools and
becomes stable before it is ejected, and dimensions and more cycle-to-cycle (commonly
the next metered shot occurs called shot-to-shot in the industry) consistency.”

Advantages of scientific molding

It’s not hard to imagine a world without scientific molding principles: product variations caused by
wide fluctuations in temperature, pressure and viscosity, increased cycle times, decreased machine
efficiency, higher costs, more rejects, and lower quality parts for customers.

As stated in our post on the advantages of scientific molding,

“Scientific molding practices are essential to achieving
outcomes that deliver faster cycles, higher volume, and
a more efficient injection molding process.” In addition,
“quality control issues can be avoided by having automated
containment control and traceability for specific applications.”

The technology behind scientific molding affords manufacturers the ability to operate more
efficiently while creating the opportunity for a global competitive advantage. It also provides OEMs
and customers higher-quality parts and fewer rejects at lower costs.

The principles and technologies involved with scientific molding solve the problem of how to get
injection molding machines to make good parts each and every time.

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 Injection Molding: Complete Guide To Scientific Molding

The role of technology in scientific molding

The advantages of scientific molding would simply
not be realized without the technological advances in
the injection molding industry. Scientific molding, as
governed by the laws of physics, is dependent upon
technology-based innovations in engineering, equipment,
and software. From machine setup to quality control and
everything in between, technology plays a vital role in
the injection molding process’s overall success.

The role of mold flow simulation software in

scientific molding
Scientific molding principles follow a data-driven approach. And data makes it possible to
improve and see repeatable results. For example, Rosti utilizes mold flow simulation software by
SOLIDWORKS®. As an up-front design validation tool for plastic injection molders, it provides
predictive insight into plastic component design. Some key benefits of using the SOLIDWORKS
software technology include:
• A shorter product development cycle and a reduced overall time to market through predictive
insight into the component design in the early stages.
• Greater insight into plastic part geometry that would otherwise be too difficult or expensive
to predict.
• The ability to identify potential problem areas upfront relating to sink marks, weld lines, short
shots, along with other part defects and blemishes.
In short, SOLIDWORKS helps injection manufacturers get the part design right the very first time.
In doing so, they’re able to eliminate costly mold rework, improve part quality, and reduce time to market.

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 Injection Molding: Complete Guide To Scientific Molding

The role of RJG in scientific molding

RJG Inc. is a training, consulting, and
technology company specializing in the
injection molding industry. A recognized
pioneer and worldwide leader in scientific
molding, RJG offers courses in decoupled
molding, high-performance molding, and
Master Molder 1 & II certification training,
to name a few.

In addition to their training and consulting

work, RJG produces the eDart process control system technology for injection molding
manufacturers. This system helps molders monitor critical information while reducing scrap, stabilizing
the process, and creating repeatable, high-quality outputs.

Rosti targets very high press utilization rates. High utilization requires flexibility from an agile fleet
of presses and a solid foundation in scientific molding. The RJG eDart system brings additional
control and flexibility to map and control highly-tuned processes with in-mold pressure sensors.

In 2009, Rosti introduced the RJG eDart system to two of our presses. As Rosti continued to convert
presses with eDart systems and molds with pressure sensors, we quickly reached a critical mass where
a plant-wide conversion became inevitable. Closed-loop process control was now ingrained into
our operating culture. In 2010, we embarked on a two-year plan to incorporate the process control
technology on all presses. The eDart system with in-mold pressure sensors has helped Rosti reach a
critical mass of technology to enhance our decoupled molding operation.

As we discussed here, “Implementing the RJG eDart system has led to transformational change in
managing part consistency across different material lots with reduced scrap and processing time.”
eDart helps produce remarkably consistent products every time by monitoring and controlling
in-mold plastic pressure variations.

Finally, some of the advantages of scientific molding with the RJG eDart system include:

The role of technology with mold flow simulation software and process control systems help enable
automation for the scientific molding operation. We’ll discuss automation support in more detail next.

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 Injection Molding: Complete Guide To Scientific Molding

How automation supports scientific molding

We’ve talked about the science of molding in
terms of the laws of physics, steps in the process
and the role technology plays in the areas of
design, engineering, and process control. But
scientific molding doesn’t end there. Not by
a long shot. It also involves and benefits from
automation and a highly-skilled workforce.

In this section, we’ll discuss the impact of

automation on scientific molding and in the
next, the importance of specialty-trained
engineers and technicians.

The invention and deployment of automated tools and robotics have positively impacted virtually
every industry. And the injection molding industry is no different. Make no mistake, the degree to
which a plastic injection molder can automate its operations, the greater it will be able to grow its
business and gain a globally competitive advantage.

The ultimate mark of a scientific molding operation is a fully-automatic production facility, like the
one Rosti pioneered beginning in 2011 at its Bunsen Drive facility. A fully-automatic facility is at
times, also called a “lights out” facility. The manufacturing process at Rosti’s Bunsen Drive facility is
so unique that the company was awarded U.S. Patent No. 8,827,674 B1 for the process: A specialized
injection molding factory system and associated facility comprising machines on the first floor with
the resin supply placed on a mezzanine level.

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 Injection Molding: Complete Guide To Scientific Molding

What does it mean to operate lights-out?

Four years ago, we published how a lights-out manufacturing facility has transformed injection
molding. In it we described the lights-out process as follows:

“Lights-out manufacturing describes the process in which factories and production

facilities are equipped with innovative and automated machinery to conduct tasks
that would normally need a human [to be] present. Essentially, the production
facility can run “lights-out” – or without substantial assistance from human labor,
lights, heat, and other costly factors for a business. Lights-out manufacturing
processes also allow companies to keep facilities running 24 hours a day, 7 days a
week without the need of multiple workforce shifts.”

In this article, we also noted that “Not only has it allowed businesses to improve in the areas of cost
and turn-around time, it has also allowed plastic part producers to lower the likelihood of defects
and increase the overall quality of products created.” We noted a number of ways in which a lights-
out facility has transformed injection molding, namely:

1. U.S. manufacturers are able to gain a globally

competitive advantage.

2. Large orders can be completed quickly without

the higher costs of adding more shifts.

3. Quality control, delivery, and cost containment

requirements are able to be reached.

4. It requires a highly-trained and dedicated

workforce to manage and maintain state-of-
the-art automation equipment and processes.
Yes, scientific molding includes the technologies of mold fill simulation software, RJG eDart process
control, state-of-the-art material handling systems, part conveyance systems, robotics, and a fully-
automated, lights-out facility.

Even so, these ever-evolving technologies and lights-out methodology do not allow a business to
run completely hands-free. In fact, without knowledgeable and highly-trained personnel, all of this
simply wouldn’t be possible.

Rosti’s mix of experienced veterans and highly motivated young professionals are vital to its
automation-focused and growth-oriented global business model. Up next, we’ll delve into the
important role specialty-trained engineers and technicians play in scientific molding.

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 Injection Molding: Complete Guide To Scientific Molding

How does scientific molding benefit from specialized

engineers and technicians
One doesn’t need to know the laws of physics or the inner workings of software and machine
technology to appreciate how scientific molding has drastically improved today’s injection molding
process. You do, however, need specially trained engineers and technicians to properly operate
science-based injection molding systems.

Specialized Training in Injection Molding at Rosti

Rosti hires and develops engineers and technicians
following a three-prong approach:

1. Two to four interns are hired each summer,

which creates a solid pipeline when future
staffing needs arise.

2. Engineers are hired from schools that have

received training and certifications in scientific
molding as well as hands-on processing.

3. We receive in-plant training from RJG on

decoupled II and III molding principles,
pressure sensor specification, and interpretation
of eDart output on a regular basis.
Rosti has established a four-level curriculum that can take a molding novice to a level where they are
prepared to take an RJG Master Molder course. The on-site training, coupled with in-house development
from the Master Molders on staff, allows for Rosti to develop future Master Molders in-house.

What is Decoupled II and Decouple III molding?

A Decoupled II process suggests filling to position, then
joins the packing and holding phases together, utilizing
second stage pressure to pack out the mold and hold
until gate seal.

Decoupled III is a process of filling to a position,

utilizing a second stage of fill or machine packing to
pack the mold to a set cavity pressure, and then holding
over time until gate seal is achieved.
Source: RJG, Inc. in PlasticsNet article on decoupled molding

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 Injection Molding: Complete Guide To Scientific Molding

Rosti engineers involved throughout entire

process window
Rosti engineers are intimately involved any variables and the parameters required for
throughout the entire scientific molding process. consistent and optimal production.
It begins early in the design specification phase
With feedback from Rosti’s senior process
with engineers working to design both the part
technicians, our engineers approve the selection
to be molded along with the tool that will be
of decoupled II or decoupled III processes for
used in the process. From there the engineer
each mold and confirm this process template
is able to specify how to incorporate pressure
for PPAP (Production Part Approval Process)
sensors in all of the new molds.
and ongoing production. Once production is
Once the sensors are in place, the tool is ready ramped up, engineers will continue to monitor
for testing under the direction and observation readings and outputs to maintain and optimize
of engineers. Testing is conducted to identify the process for the best possible outcomes.

Where does design for manufacturing fit into the scientific

molding process?
Design for manufacturing is a top consideration for reducing costs in scientific molding. The first
company to commercialize design for manufacture and assembly (DFMA), Boothroyd Dewhurst,
Inc., found that 80% of the cost of a new product is directly related to design.

According to John Gilligan, President of

Boothroyd Dewhurst, Inc., “The use of DFMA
to help choose the right structures, materials,
processes, and labor has become critical given
that companies get few second chances in
today’s global markets.”

Therefore, the best time for a tool-maker/

injection molder to get involved in the design
process is early in the development cycle.
Doing so will help to best understand customer
objectives and avoid unexpected surprises.

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 Injection Molding: Complete Guide To Scientific Molding

In Rosti’s comprehensive guide to design for manufacturing in plastic injection molding, we’ve laid
out a four-part approach to design optimization. They are as follows:

Design for Manufacturing

Design for Manufacturing (DFM) describes the process of designing or engineering a product to
reduce its manufacturing costs, allowing potential problems to be fixed in the design phase, which is
the least expensive place to address them.

Design for Functionality

Throughout the plastic part design process, it is imperative to keep focus on the functional
requirements of the part. Experienced design engineers should make recommendations about
modifications that will help ensure the part meets its functional requirements including what
elements the part will be exposed to, chemical or corrosive materials the part will need to withstand,
functional cosmetic attributes, and more.

Design for Assembly

Design for assembly (DFA) is a process by which products are designed with ease of assembly in
mind with the ultimate goal of reducing assembly time and costs. The reduction of the number of
parts in an assembly is usually where the major cost benefits of DFA occurs.

Design for Sustainability

Design for sustainability focuses on designing parts with print measurement intent in mind -
sustaining tolerances with proper measurement on an ongoing basis.

The scientific molding process is all about manufacturing parts

as efficiently as possible with fewer defects while reducing
costs and increasing production. Design for manufacturing
cannot be overlooked as an essential element for customers
and manufacturers alike.

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 Injection Molding: Complete Guide To Scientific Molding

Why does material selection play such an integral role in

scientific molding?
According to Kip Doyle, author of an article
on the Top 10 Reasons Why Molders Fail at
Scientific Molding, many molders can’t get
past a “machine-focused” approach and mold
from the plastic’s “point of view.” He cites that
many articles have been written on the four
primary plastic variables (plastic temperature,
plastic flow, plastic pressure, and plastic cooling
rate and time), and a scientific molder must
understand this approach and the process
optimized from the perspective of the plastic.

Aligning with your injection molding partner to choose the best resin early in the design for
manufacturability process, is crucial to a part’s production success. A good place to start is to have a
general understanding of the two main types of resins – amorphous and semi-crystalline.

Polymers are made up of structures that are defined in terms of crystallinity – or how the molecules
of the polymer are packed together.

Crystalline structures are, in most cases, very ordered, which gives the material strength and
rigidity. Amorphous polymers are the opposite. Sometimes the distinction between the two is not
clear cut. With most polymers, there is a mix of both crystalline and amorphous structures. How
the polymer is processed determines the exact proportion of each.

In our post on Preparing for Injection Molding Resin Selection, we break down the differences in
polymers further.

When considering the intended end use for your injection molded part, understanding these key
characteristics is essential to selecting the best resin.

Part Appearance and Geometry

A part’s overall appearance and geometry have a significant impact on the molding capability and the
type of resin that should be used. Part design, including size, shape, and wall thickness, can make a
part prone to defects, while features like snaps, undercuts, bosses, ribs, and more can complicate the
molding process.

It’s critical that injection molders use the latest technology to run simulations to optimize mold
design specifications and resin choice before a project is finalized for production - this is where
SolidWorks Premium plastics flow simulation provides predictive insight in the early stages.

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 Injection Molding: Complete Guide To Scientific Molding

Part Strength and Flexibility

Material selection also plays a critical role in the strength and flexibility of your molded part.
Addressing specific needs early in the design process can help you avoid costly changes later.
Balancing characteristics like stiffness, durability, toughness, and others are key in achieving optimal
part functionality.

Using Additives
When material performance cannot be achieved with available resins, custom blends of materials can
be created to boost the properties of multiple resins. Reinforcing materials with additives can build
strength into parts and add stiffness that may reduce warping and shrink. Additives like glass or
carbon fibers can be used to enhance part performance and improve flow, ejection, and dispersion.

High Heat Materials

We mentioned the important role of design
in the injection molding process, and this is
of particular concern when high-temperature
materials are used to heighten a part’s strength,
stability, and other features that are imperative
to its unique application. Conventional molding
techniques are not always effective with high-
temperature and exotic resins.

Some characteristics of high heat and exotic resins are unique and may perform differently from
one application to another. To realize both the design and material’s fullest benefits, experienced
design engineers and injection molders have a number of factors to consider. In this post, outlined
are a few basic and advanced tips that should be taken into account when designing parts for
injection molding with the use of high-heat or exotic resins.

Learn more about Rosti’s design

tips for injection molding
with high heat or exotic resins.

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 Injection Molding: Complete Guide To Scientific Molding

Calculating plastic residence time

Plastic residence time is the time that
plastic or resin is subjected to heat
during fabrication.

Taking the time to calculate the specific

plastic residence time for the relevant
manufacturing process will improve your
material performance and the overall
final product.

Understanding the residence time of material in the first stage of the screw can help you understand
the optimal time and temperature for your manufacturing needs.

What does plastic residence time affect?

If plastic residence time is too long, it can affect Using scientific molding practices, Rosti uses
part quality in several different ways: recorded data to assess quality control and make
any needed tweaks to tooling, thus improving
• General weakness in parts produced
overall part quality and avoiding the negative
• Color variation
effects of poorly calculated plastic residence time.
• Degradation not visible to the eye
• An overall compromised product Plastic variables require understanding the
nature of the material to be molded and
However, it can also impact machine
its preferred molding conditions. When a
performance, resulting in inconsistency in the
material’s key characteristics, behavior, and
melt quality and shot weight, as well as the melt
response to processing is understood, scientific
temperature.
molders can optimize the molding process to
No matter how many shared formulas or produce the most consistent part possible.
calculations, plastic residence time should be
calculated by each individual manufacturer in
order to determine the ratio that works for their
particular product.

Learn more about the importance of

calculating plastic residence time here.

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 Injection Molding: Complete Guide To Scientific Molding

What attributes of scientific molding are used in part

design and tool optimization?
The creation of tools for prototype and
production components represents one of the
most time-consuming and costly phases in the
development of new products. To reduce the
manufacturing lead-times and cost, prototyping
and manufacturing processes have been rapidly
developed through the evolution of scientific
molding practices.

Scientific molding involves using data to develop a process that produces repeatable results with little
to no variation. Through resin expertise and testing, dimensional and mechanical characteristics of
a molded part can be optimized. Often achieved through the use of mold fill simulation and process
control systems, predictive insight, process validation and complete process documentation are vital
to producing demanding parts.

Part Optimization
Design engineers should lean on past learnings and expertise in optimizing part design for unique
applications. Scientific molding elements associated with part design may incorporate using the
latest software and technology, including computer-aided engineering, mold flow, and prototype
development that will validate the part’s end-use.
• Design considerations may include: • Weld line locations
• Radius, draft angle, sink marks, wall • Environmental / end-use factors
thickness, etc.
• Part aesthetics
• Gate location

Injection molders should understand how to avoid designing a part, building the tooling, and
beginning the molding process only to find out that the design does not work in production.
Prototype tooling is an excellent method to validate and optimize critical mold and scientific
molding variables.

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 Injection Molding: Complete Guide To Scientific Molding

Tool Optimization
Scientific molding practices can also be used
to optimize tool design or to optimize poorly
designed tools. It is essential for injection
molds to be evaluated for their performance
in the production of consistent, defect-free
parts. Engineers should examine every aspect
of a mold’s mechanical functionality using the
appropriate material settings.

Testing can then be applied to check for any

imbalances among cavities. When this analysis
is complete, a gate seal study can be performed
to gather data on where the gates seal fully at
what points in the mold cavities. Recording
findings and making recommendations for
adjustments in the process or tooling are
essential to correcting potential defects.

How do quality control resources impact scientific

molding processes?
Recorded data can be used to assess quality As it continues to evolve, scientific molding
control and make any necessary tweaks to has helped optimize injection molding
tooling - improving overall part quality. production processes in a way that now allows
Once all quality parameters have been met, manufacturers to lean on technology that creates
the implementation of scientific injection an even greater global competitive advantage.
molding practices help to greatly streamline
the production process. These actions can be
so effective that less involvement is needed by
both machines and operators. In fact, cutting-
edge injection molders have begun instituting
revolutionary lights-out manufacturing
practices. This is where factories and production
facilities are equipped with innovative and
automated machinery to conduct tasks that
would normally need the presence of a human.

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 Injection Molding: Complete Guide To Scientific Molding

How has scientific molding transformed injection molding

The advancements in scientific molding practices have impacted the plastics industry at a high level.
Not only has it allowed businesses to improve in the areas of cost and turn-around time, but it has
also allowed plastic part producers to lower the likelihood of defects and increase the overall quality
of products created. Other examples include:

Competitive Advantage
When designing and producing complex injection molded parts, there is a lot of advantage to having
a partner that is implementing state-of-the-art processes but also easily accessible from a geographic
standpoint. Many companies are realizing the benefits to having their manufacturing partners
close. The ability to react quickly and make important changes on a tight timeline is an important
factor that comes up often in selecting a manufacturer. When production facilities adopt advanced
manufacturing processes, including lights out functions, it communicates to their partners that they
are working and producing parts as efficiently as possible.

Quicker Turnaround with Lower Cost

When manufacturing processes are set up and monitored in a smart and data-driven way, companies
see their production capacities increase and orders completed at a much faster rate. While not
appropriate for every job, automated molding is best for jobs that run at medium and high volumes,
about 2,000 hours per year or more.

Additionally, the capacity, speed, and labor efficiencies created by scientific molding practices can be
passed on to the customer – ultimately lowering overall product costs. When managed appropriately,
the process improves OEM production flexibility as well.

Highly Trained Workforce

When we talk about automation, lights out
manufacturing, and other scientific molding
offerings by an injection molder, much of the
emphasis is placed on the positive attributes
associated with reducing human labor. While
the process can create a more streamlined
approach to production and may enable fewer
people to be involved, not all projects can be run
by technology. State of the art technology and
processes require a highly trained and dedicated
workforce that can make smart decisions and
maintain equipment.

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 Injection Molding: Complete Guide To Scientific Molding

Protection for Intellectual Property

When product manufacturers rely on innovation and speed to market to be competitive in their
industry, offshoring various aspects of production can expose designs to patent infringement,
counterfeiting and more. Working with a reputable and knowledgeable partner that keeps
everything from design, development, and production under one roof, will ensure that the
manufacturer protects and retains all intellectual property, as well as learnings that are acquired
throughout the process.

Is it more costly to use an injection molder that

implements scientific molding processes?
You can save money by partnering with a
molder who uses scientific molding processes
to intelligently design molds and validate
parts. When molds are smartly designed, less
material is used, and defects are reduced - both
contributing directly to reduced costs.

Additionally, working with an injection molder

who can identify opportunities for improvement
during a design for manufacturing analysis
will result in significant savings. Identifying
problems in the early stages such as radius, draft
angle, wall thickness, gate location, and other
moldable features will eliminate financial and
cosmetic issues along the way. In fact, as much
as 80-percent of manufacturing costs can be
determined by design decisions.

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Why Rosti for your next scientific molding project?
Scientific molding is a systematic and comprehensive approach to creating the efficiencies, cost
structure, and production capabilities required for a manufacturer to compete on a global scale.

Implementing scientific molding practices has equipped Rosti with the ability to provide both superior
quality and cost savings to our customers. In using highly advanced technology and processes, we are
able to more efficiently produce parts while lowering the frequency of quality checks needed to ensure
good parts. Rosti’s highly-trained and knowledgeable team provides our customers with confidence that
their products will be produced consistently from part one to part 2,000,000 and beyond.

Would you like to learn more about Rosti’s scientific molding practices? To hear about our approach,
or to discuss your next project, contact us today!

CONNECT WITH ROSTI

Are you looking for an injection molder that can provide expert
consultation from the design of your metal to plastic conversion
project - straight through to production completion?

Connect with Rosti’s knowledgeable team members

who will focus on all areas of design, development, and production.

Lilla Nygatan 7, 5 tr, SE-211 38 Malmö, Sweden

+46 40 204 701 • Rosti@Rosti.com
www.Rosti.com