Productive Ideas Blog

Part Size Has a Big Impact When Choosing Between Injection Molding and Plastic Thermoforming

Part Dimesion Impact on Plastic Thermoforming vs Injection Molding

When comparing a part manufactured with the heavy gauge plastic thermoforming process and the injection molding process, next to production volume, the largest factor that can impact the cost and even process feasibility is the size of the part.

Essentially, the larger the part is, the more expensive it becomes to produce with injection molding. Comparatively, part size has a very minimal cost effect on plastic thermoformed parts. The breakeven point on cost between the two manufacturing processes, with respect to annual production volume (Deciding Between Plastic Thermoforming and Injection Molding – The Choice is Not Always Obvious), increases as part size increases to approximately 5,000 parts or higher depending greatly on how large the part is.

Why Does Part Size Affect Cost and Manufacturing Process Selection?


The injection molding process requires a very large initial capital investment in the tooling and equipment needed to produce a part. This is because the nature of the process involves a very highly engineered 2-sided mold to create a part by feeding thermoplastic resin into a heated barrel with a rotating screw. The screw delivers the raw material forward collecting under pressure the amount required to fill the mold cavity and then injecting into the mold at high pressure and velocity. This action requires highly structured molds and equipment capable of withstanding very high clamping pressure.

As part size and dimensions increase, the complexity of design, engineering, and calibration required to construct, install, and process this 2-sided mold results in a significant increase in the cost of equipment, tooling and setup. The per-part production cost and lead time may also see an appreciable increase as the part size increases requiring much more robust molds and equipment. These increased capital expenditures will result in greater investment and overhead costs calculated in the piece price. Injection molding machines have a limited total mold size capability but can often accommodate multiple parts within the construction of a mold. Smaller part sizes equate to a higher number of parts manufactured per mold and machinery cycle. Larger part sizes decrease the number of parts that can be manufactured per mold and cycle.

Think of a muffin tray with 3-inch diameter muffin molds. Now take that same size tray but with 6 or even 10-inch diameter muffin molds and you imagine the impact on production and cost. In fact, most standard injection molding machines can only accommodate a maximum part size of 4’ x 4’. Larger machinery is available but is also drastically more expensive.

The heavy gauge plastic thermoforming process, on the other hand, involves considerably less pressure and most applications only require a single one-sided tool to produce a part. Additionally, only one part is formed per cycle in heavy gauge thermoforming applications. Consequently, the initial tooling investment is drastically reduced. While an increase in part size will still increase the tooling investment, the impact on cost is substantially less when compared to injection molding. Heavy gauge thermoforming equipment has oven zoning and variable sheet size capabilities which allow for a wide range of part sizes to be efficiently formed from the same equipment investment. The nature of the thermoforming process and flexible capacity capabilities makes scaling production for larger part sizes a relatively easy process. Since most heavy gauge thermoforming operations utilize cell-based manufacturing and CNC part trimming, a larger part can be produced with little impact, other than increased material, on per part cost, cycle time, and lead time. Thermoforming machinery can also manufacture part sizes as large as 10’ x 18’ providing a much larger part size capacity than injection molding.

Large part size infographic


Deciding Between Plastic Thermoforming and Injection Molding – The Choice is Not Always Obvious


Injection Molding vs Plastic Thermoforming - Deciding when the choice is not obvious

Both injection molding and plastic thermoforming have widespread uses in a long list of industries. Each process has some unique features and benefits that are often advantageous for a specific application. In these instances, the choice to manufacture with plastic thermoforming or injection molding may be very obvious. This is most apparent in production volume. Low to mid volume tends to favor thermoforming, while high volume is usually more cost effective with injection molding.

However, a product’s needs and the capabilities of these two processes sometimes overlap. A part’s geometry may seem better suited for injection molding, but in a limited production run, but it may be drastically more cost effective to manufacture it with plastic thermoforming. This is just one example of an application where deciding between injection molding and plastic thermoforming may not be a clear choice. Selecting the right method in these situations requires a deeper appraisal of the features, benefits, and costs associated with each process.

The Clear Choice

As mentioned above, there are some instances when the type and specifications of an application drastically favor one or the other plastic manufacturing process when the choice is between injection molding or plastic thermoforming.

Injection Molding

Injection molding offers the key benefit of cost effectiveness at the mass production scale. When an application requires the production of more than 3,000-5,000 Estimated Annual Usage (EAU) identical parts with uniform wall thicknesses, injection molding often is the clear choice. This can be attributed to a high upfront tooling investment that is gradually offset by a generally low per unit manufacturing cost. The volume range of 3,000 – 5,000 is due to a variation on part cost in respect to part size. Smaller parts are generally cheaper to manufacture than larger.

  • Part production volumes > 3,000- 5,000
  • Uniform part wall thickness required

Plastic Thermoforming

Plastic thermoforming, on the other hand, has a substantially lower tooling investment and a slightly higher per unit Cost comparison for tooling and parts, pressure forming vs. injection moldingmanufacturing cost. This equates to a much lower total part cost at low to moderate part volumes. Plastic thermoforming becomes the clear choice when the volume of manufacturing is less than 3,000 – 5,000 parts per estimated annual usage. This process also has the capability to produce single parts with very large dimensions, whereas the injection molding process is limited to single part sizes of about 4 feet x 4 feet.

  • Single part dimensions > 4’x4’
  • Part production volumes < 3,000 – 5,000 EAU

Considerations When the Process Choice Is Not Clear

If your part or project doesn’t require a uniform wall thickness, large single part dimension, or has a volume requirement that is in the mid thousands, then you have landed in an area where the capabilities of plastic thermoforming and injection molding may overlap, and your process choice is not so obvious.

The good news is that you are now no longer handcuffed to a process that, while cost or size necessary, may not have the most comprehensive scope of benefits that would contribute the greatest to the success of your project.

Here are some points to consider for each process that can be taken advantage of or avoided now that you are free to choose a manufacturing method better suited to your project’s needs.

Plastic Thermoforming:

  • Large single part capability (maximum dimensions approximately 10’ x 18’)
  • Short lead time ( 6-12 weeks )
  • Able to reproduce injection molded level detail
  • Smaller investment in tooling
  • Lower equipment capital investment leads to lower set up and machine time costs
  • Can produce thinner wall parts than injection molding, resulting in weight savings
  • Greater options for part surface finishing (textures, patterns, distortion printing, painting, etc.) that can be accomplished in the mold.
  • Multi material structures for cosmetic and engineering structure options (e.g. Acrylic/ABS)
  • Variable part wall thickness depending on depth of draw
  • Improved cost effectiveness at lower to mid volumes (< 3,000-5,000)
  • Lighter part weight compared to injection molding for most applications
  • Less molded in stress than injection molding
  • Twin sheet capability for hollow parts and added structure

Injection Molding:

  • Longer lead time (22-24 weeks)
  • Large investment in tooling
  • Cost effective at high volumes ( > 3,000 – 5,000)
  • Efficient material use
  • High level of precise part detail
  • Limited single part size capability (maximum dimensions approximately 4’ x 4’)
  • Finished parts often require post processing painting or finishing
  • Greater design freedom on single wall parts

Want More Information?

What you see above is just the tip of the iceberg when it comes to comparing these manufacturing processes. For more information and for assistance in choosing the right process for your project, please contact Productive Plastics and connect with our industry experts and engineers to see how we can put over 62 years of manufacturing experience to work contributing to your project’s success.


Please contact Productive Plastics for more information on the thermoforming process
Please download our complimentary thermoforming design guide for more information on the thermoforming process

Top Plastic Thermoforming Content from 2017

Productive Plastics covered many topics last year on the features, benefits, and capabilities of utilizing the plastic thermoforming process to manufacture custom parts and enclosures for your projects. If you missed any, here is a quick recap, with links to content and data, that we hope you will find informative and useful.


Upgrades at Productive Plastic Enhance Plastic Thermoforming Solutions for Your Project

Your Project's Success is our Goal with Plastic Thermoforming

Productive Plastics has been around for 62 years. In over six decades of heavy gauge plastic thermoforming, one of the many lessons we’ve learned is that helping a customer’s project achieve success means a commitment to the constant evolution of every facet of our business. It’s one of our core values.

This year we invested in numerous upgrades. We expanded our resources, expertise, technology, and machinery, all designed to move us further down our technology roadmap as we implement industry 4.0 solutions and capabilities. And we continue to bring you dynamic and comprehensive heavy gauge plastic thermoforming solutions of the highest quality.

Investments at Productive Plastics This Year:

  • More engineering expertise in-house
    • The engineering team grew by 75% this year to provide our customers with top tier technical support, aid in implementing emerging plastic thermoforming innovations, and expand the scope of our value-added services. Welcome to our newest members who joined the engineering team.
      • Bob Cardona – Engineering Manager
        • Engineering team leadership and coordinating implementation of new technologies
      • Don Stiger – Applications Engineer
        • Providing plastic thermoforming engineering support to customers for new projects and part conversions
      • Dan Govender – Applications Engineer
        • Providing plastic thermoforming engineering support to customers for new projects and part conversions
      • Skip Grant – Manufacturing Engineer
        • Overseeing advances in process improvements
      • Bryan Alicea – Engineering Intern
        • Supporting the engineering team and customer on thermoforming applications

Left to right: Bryan Alicea, Don Stiger, Skip Grant, Dan Govender, Bob Cardona


  • Additional Sales Support

    John Zerillo

    Yordano Alicea

    • Yordano Alicea has joined John Zerillo, Principal and VP of Sales, in the field as our newest Sales Account Manager. He adds yet another expert resource available to support customers through every step of the product development cycle.
  • New Technology, Machinery, and Process Upgrades on the Manufacturing Floor
    • 4′ x 6′ Advanced Single Station Pressure Forming Machine
      • Advanced controller and sensor system for increased process control
      • Advanced ovens for better consistency in forming
    • 4’ x 6’ Advanced Rotary Pressure Forming Machine
      • Rapid setup time capable
      • Processes plastic material more efficiently
      • Advanced controller and sensor system for increased process control
    • 6 Axis Robotic Arm Cell
      • Automates cell setup for faster operation
      • Removes human errors
  • Process Refinements to In-Facility Painting Operation – Productive Industrial Finishing
  • What are the Benefits for Your Project?
    • Higher Quality and Consistent Parts (tolerances, color, mating points, etc. – whether it’s 2 parts or 2,000)
    • Faster Lead Times
    • Stronger Value at Competitive Investment
    • Comprehensive Solutions
    • A More Flexible and Dynamic Supplier

This year was about laying the foundations for taking our manufacturing processes and value-added capabilities to the next level, to Industry 4.0 and beyond. New machinery, more automation, moving critical processes in-house, advances in technology, and expanded expertise were all added this year to increase our ability to contribute to your project’s success.

We invite you to contact us and schedule a time to tour our facility. We would like the opportunity to show you just how we can contribute to your project’s success and how we can provide much more than a high quality plastic part.

Please contact Productive Plastics for more information on the thermoforming process



Thermoplastics in Transit Interiors – Weighing the Advantages

Advantages of plastic thermoforming for transportation interiors

Requirements for greater fuel efficiency, the desire of riders for high-quality riding experiences, and the need for enhanced safety have altered mass transportation (mass transit buses, railcars and aerospace) design and manufacturing processes.  Using buses as an example, design teams and OEMs have replaced steel and aluminum components with thermoplastics and thermoplastic composite materials.  Upgrading to thermoplastic components typically results in a 55% weight savings and meets the static loading requirements of the American Public Transportation Association.  With material options that are industry compliant, rigid, and durable, and a manufacturing process that enhances design capability and lead time, thermoplastics are being used more and more in transportation.

Why Reduce Weight?

Because the mass of any vehicle has a direct relationship to fuel consumption, designers continually seek materials that reduce the overall weight of the passenger buses, railcars, aircraft, and other transportation units.  Reducing vehicle weight leads to decreased energy consumption, less brake and tire wear, and lowered emissions.  For example, cutting vehicle weight by 110 pounds reduces 5 g of carbon dioxide emissions per kilometer and increases fuel economy by two percent. (Source: “Vehicle Weight Reduction for Optimal Performance” – DuPont

Modern transportation vehicles are becoming lightweight and fuel-efficient because of the use of thermoplastics for many interior components. Door, wall, and ceiling panels, dashboard surrounds, window masks or shrouds, seatback shells, armrest shells, bulkhead components, luggage racks, and display housings are just a few of the interior components that can be manufactured with the heavy gauge thermoforming process.  While the materials industry as a whole has focused on lightweight solutions, thermoplastics offer a complete answer through a combination of strength, rigidity, and low density.  For example, thermoforming produces components that weigh 30% less than comparable components made from fiberglass and 250%  less than aluminum components. Interior components made from thermoplastics may make up nearly half of the volume of an automobile.  However, those same, now lightweight components, contribute less than 10 percent to the weight of the vehicle. (Source: “A Lighter Future with Thermoplastic Solutions”, Lightweighting World.)

Industry-Compliant Thermoplastics with Emphasis on the Environment

The benefits of thermoplastics go beyond lightweighting.  Interiors for aircraft, coach and city buses, trucks, and passenger rail cars require the use of flame retardant materials that meet smoke and toxicity standards.  More specifically, all coach and city buses in the United States must meet the U.S. Department of Transportation Docket 90 safety specification for flame spread and smoke emissions. Motor Vehicle Safety Standard 302 Fire Test requirements apply to interior trim parts used for trucks.  One example of a material now commonly used for interior aircraft components and interior rail applications is amorphous polyetherimide (PEI). This superior thermoplastic material complies with flame, smoke, and toxicity standards while providing strength and aesthetic appeal Along with meeting compliance standards, PEI thermoplastics also resist damage caused by exposure to halogenated hydrocarbons, alcohols, and aqueous solutions.  In addition, PEI thermoplastics resist warpage when exposed to heat for long durations because of a heat distortion temperature rating of 350o F.

The manufacturing process for fiberglass emits high levels of volatile organic compounds (VOCs).  In contrast, the use of very long fiber-reinforced polypropylene (PP VLF) thermoplastic compounds reduces levels of VOCs to compliance with the open air and enclosed application specifications set by international legislation and automotive OEMs. In addition,  the PP VLF thermoplastics meet or surpass standards for odor and fogging.

Parts manufactured from fiberglass cannot be recycled.  However, parts made from PP VLF thermoplastics can be recycled, have a lower life-cycle energy footprint and a lower life-cycle greenhouse gas emissions. Manufacturers of mass transportation components use PP VLF thermoplastics for instrument panels, overhead and center consoles, seating, and storage bins.

Achieve Aesthetic Appeal On Time and Within Budget

Thermoplastics can improve the aesthetic design features of interior components used for mass transportation vehicles at a fraction of the cost required to obtain the same level of complex designs with other manufacturing processes. Low or high gloss surface finishes, custom surface texturing, complex geometric part design, and coloration are all capable, cost feasible, and can be manufactured quickly with the thermoforming process.

In-mold design and decorating enables the manufacturing of these high-level design features, resulting in part construction with consistency, precision, and a negligible impact on part cycle time. While in-mold texturing and pre-textured plastic may require a slightly higher initial investment than a simple design, the process ensures consistent part-to-part aesthetic detailing and minimizes cost by eliminating additional labor or processing.  As a result, in-mold design can produce complex designs and custom surface finishes with a minimal impact on cost and lead time.

The use of thermoplastics in component production also provides the option of producing plastics with coloration.  Thermoplastic providers can produce integral colored materials that resist stains, graffiti, and chemicals and that do not chip or vary in tone or color.  Moreover, using integral colored plastic eliminates the added cost and lead time of post-production painting. Coloration allows manufacturers to achieve a desired color finish and precise color matching along with durability.  The technique also allows providers to offer thermoplastic components that have specialty finishes, such as wood grain or metallic patterns and overlays, for a greater range of design capability.

Aesthetic appeal also is achieved through geometry and a seamless appearance.  Thermoformed materials respond to the desire for design freedom through the versatility in the fabrication process, pliability, and the capability to transfer imaginative design to a usable product. Manufacturers can take advantage of the thermoforming process to build complex geometric designs with precise part mating and give the appearance of nearly seamless multi-part assemblies.  Again, these complex designs are accounted for within the part’s tooling, with minimal impact on cost or lead time.

Productive Plastics is a heavy gauge thermoforming custom components manufacturer, with vast experience with thermoplastic manufacturing for transportation applications. Contact us for more information.


Please contact Productive Plastics for more information on the thermoforming process
Please download our complimentary thermoforming design guide for more information on the thermoforming process

Plastic Thermoforming for Transportation Interiors

Plastic Thermoforming Applications for Transportation InteriorsIf you have traveled within North America on mass transportation in the last 3 to 4 decades, specifically on rail or bus, then you are familiar with the typical outdated interior layout and design of most transportation vehicles in the USA.

Often you will see off-white or beige-colored fiberglass wall paneling, seating, and window masking, likely chipped or cracked at many corners or high traffic areas. Some of these components may be constructed from scratched and dented sheet metal with exposed fasteners and attachment points. The design features are lacking aesthetic appeal or any integrated technology. Boxy, straight-lined components cover the interior with large gaps between mated parts. This is all standard fare for commuter mass transit, railcar, or passenger bus interiors and has been for the past 30 years or more.

Most of the transportation interiors in the USA, except for aerospace, were designed and manufactured in the mid to later part of the last century. These interior components were most commonly manufactured from materials such as fiberglass and sheet metal. The old parts are heavy, require frequent maintenance due to durability issues, and lack modern design aesthetics. In short, the time has arrived for major updates and upgrades in this market.

In fact, over the past few years, the upgrade trend has already started as industry and environmental compliance standards have evolved and the demand has increased for more efficient, lightweight, and modern passenger transportation vehicles and interior designs. Rail, bus, and other mass transit manufacturers are now looking to take advantage of available new processes and innovations to develop the next generation of transportation interiors.

Thermoplastic materials and the plastic thermoforming process are uniquely suited to the emerging needs of the transportation interiors industry, offering extremely lightweight and durable materials that meet industry standards such as FST, Doc 90, and FMVSS 302. The thermoforming process also enables a much higher design flexibility for interior components at a very attainable cost. Features such as undercuts, advanced tooling, and tooling imbedded surface finish options make benefits like complex geometric parts, closely mated component assemblies, surface texturing, and a wide variety of paint free pre-colored material options available to designers and engineers. Such benefits are not achievable or cost prohibitive with many other manufacturing processes.

This blog and our email newsletters will take a deeper look into plastic thermoforming and its applications for the transportation interiors industry over the next few months.

Also, if you haven’t already done so, please download our Fiberglass to Plastic Thermoforming Comparison and Conversion Guide, Metal to Plastic Thermoforming Comparison and Conversion Guide, or Heavy Gauge Plastic Thermoforming Process and Design Guide for more comprehensive information on plastic thermoforming capabilities and solutions.

Download Fiberglass Guide Icon

Download Metal vs. Plastic Thermoforming - Comparision and Conversion Guide from Productive Plastics

Download our NEW Metal vs Plastic Thermoforming Comparison and Conversion Guide


Download Productive Plastics Metal vs Plastic Thermoforming Comparison and Conversion Guide

The team at Productive Plastics has put together a comparison guide for converting parts and components from metal to plastic thermoforming. The guide is full of useful information from basic overviews to technical comparison data on materials and processing.

What you will find inside the guide:

  • Metal and Plastic Thermoforming Process Overviews
  • Material Weight Comparison
  • Process and Material Performance Comparisons
  • Materials and other Considerations
  • Upgrading your Metal Application to Plastic Thermoforming

Follow the link below to instantly download a PDF copy of the Metal vs Plastic Thermoforming – Comparison and Conversion Guide

Download Metal vs. Plastic Thermoforming - Comparision and Conversion Guide from Productive Plastics

Metal vs. Plastic: 5 Key Comparisons

Metal vs. Plastic - 5 Key Comparisons

Metal versus plastic is an old argument and it’s likely that you or your company have previously compared them for past projects. However, innovations in both plastic materials and process capabilities, coupled with changes in industry demands have closed many of the physical and cost performance gaps that once existed between metal and plastic.

Many industries, such as aerospace, medical devices, and mass transit, are realizing the potential of the updated advantages of replacing large scale, interior, or enclosure metal parts with plastic materials and manufacturing processes, such as thermoplastic materials and the plastic thermoforming process.

Below are 5 key comparisons to consider for METAL VS PLASTIC:

1. Weight

Heavy weight equals heavier costs. Fuel efficiency, maintenance costs, logistics, installation – all see significant cost reductions in tandem with a decreased part weight. Referencing the chart below, you can see that this is a major advantage that plastic has over metal.

If you were to take a part made from steel and compare it to the same part made from thermoplastic, the plastic part could be more than 6 times lighter.

Take that same part, now manufactured with aluminum, and the plastic version would be approximately half the weight.

Plastics / CompositesSpecific Gravity
Acetal copolymer1.41
Acetal, 20% glass composite1.55
High-impact ABS1.03
MetalsSpecific Gravity
Aluminum2.55 – 2.80
Carbon Steel7.8
Cast Iron7.03 – 7.13
Cast Rolled Brass8.4 – 8.7
Stainless Steel7.7
Tool Steel7.70 – 7.73
Tungsten Carbide14.29

The Specific Gravity – SG – is a dimensionless unit defined as the ratio of density of the material to the density of water at a specified temperature.

(There are a multitude of grade and alloy variations of steel and aluminum, and there are just as many diverse formulations of plastic material. For more accurate weight comparisons, reference the specific material manufacturer’s data sheets for the applicable materials for your project – view plastic material datasheets.)

2. Strength-to-Weight Ratio

In the past, one of the biggest roadblocks to replacing metal parts with plastic was that plastic, while much lighter, could not compete with the strength characteristics of metal. Now, with advances in plastic composites and the addition of carbon fiber or other glass fibers to plastic material formulations, thermoplastic products can perform as well as and in some cases even outperform metal in ratios such as strength-to-weight and strength-to-stiffness.

Strength-to-Weight Ratio, also known as Specific Strength, is a material’s strength (force per unit area at failure) divided by its density.

When referencing the chart below note that examples of thermoplastic reside in the composite and polymer categories and that this data may not include all thermoplastic material products, many of which are specially formulated to compete with metal and alloys in strength and stiffness. Data for these materials can be found on thermoplastic material manufacture websites.

Source – By Nicoguaro – Own work, CC BY 4.0

3. Strength-to-Stiffness Ratio

Strength-to-Stiffness Ratio, also called Specific Modulus, is a material’s property consisting of the elastic modulus per mass density of a material.

4. Production/Lead Time

Whether you’re trying to meet a deadline or fill orders for an increase in demand, time to market can be an essential factor to the success of any project. With a dramatically less labor intensive process, plastic thermoforming can save production time, energy, labor, and cost compared to manufacturing components from metal processes.


Plastic Thermoforming ProcessMetal Fabrication Process
Plastic Thermoforming Processmetal vs plastic thermoforming process
• Programing

• Tooling construction

• Automated part forming

• Robotic part trimming

• Part finishing (bonding attachment points)

• Fixture/die construction

• Programing

• Cutting, bending, welding

•Cleaning welds, finishing

• Paint preparation

• Painting

5. Design Capability and Cost

You don’t have to watch the sheet metal fabrication process for very long to take away the fact that metal can difficult to work with and shape. Even with today’s technology, metal’s inherent characteristics prohibit complex part designs or shapes, such as compound curves or fluid designs from either a material capability or cost limitation.part complexity cost comparison chart metal vs plastic

Shaping a metal part can require die work, welding, grinding, rework, or bending on each individual part produced to achieve design specifications and desired look. In addition to greatly increasing production and lead times as mentioned above, as part design complexity increases, part cost increases at an exponential rate.

The same increase in part design complexity has a relatively minimal impact on the cost of a part manufactured with the plastic thermoforming process.  This is because complex designs, shapes, branding, and surface textures can be incorporated directly into a part’s tooling. While this may add a slight increase in the upfront tooling cost of the part’s production, it will not add any additional secondary or shaping labor operations that would affect part cost or production time. This method and the nature of thermoplastic also offer a much larger scope of design complexity capabilities and options that are unavailable to metal manufactured parts (see Thermoforming Material Selection: 5 Ways Thermoplastic Materials Can Influence Product Appearance).

Productive Plastics is a heavy gauge thermoforming custom component manufacturer, including vacuum forming and pressure forming processes. Contact us or request our complimentary thermoforming design guide for more information.

Please contact Productive Plastics for more information on the thermoforming process
Please download our complimentary thermoforming design guide for more information on the thermoforming process


Should You Upgrade Your Sheet Metal Parts and Enclosures to Plastic Thermoforming?

Plastic Thermoforming vs Metal

The heavy gauge thermoforming process offers key advantages as an upgraded replacement for many parts currently manufactured from metal. Weight reduction is a key advantage – plastic parts are lighter than metal. Further, custom plastic thermoforming can be used to produce complex geometric part shapes that are not possible with sheet metal at a feasible cost, allowing greater design freedom. This versatility gives manufacturers faster design and production cycles, while also providing the opportunity for innovation with structure and design. Additionally, thermoforming can eliminate the need for secondary part finishing. The industrial market demands lightweight and durable products and high levels of customization, with an eye towards environmental concerns about the use of recyclable materials. Custom heavy gauge thermoforming meets these demands better than sheet metal.

The Impact of Thermoplastics on Industries

Thermoforming can present a substantial upgrade over traditional sheet metal fabrication, metal stamping, metal spinning, and metal casting manufacturing processes and materials. Although sheet metal fabrication exists as a low-cost method for producing parts, the use of sheet metal sacrifices flexibility in design, capabilities, and application. Complex parts manufactured with sheet metal require secondary processes that can involve cutting, bending, welding, and bolting. Producing the same part with thermoforming can eliminate these secondary processes by easily incorporating complex 3D part designs, mating points, and various surface finishes and branding directly into the part’s tooling.

Medical Device with Plastic Thermoformed Enclosure

Large medical device with plastic thermoformed enclosure. Complex shape design and continuous design lines spanning over multiple parts.

The same differences become apparent when comparing metal stamping, metal spinning, and metal die-casting with thermoforming. Manufacturers use bending and stamping to produce low-cost parts that have a simple geometry. Any attempt to add complexity to a part requires additional assembly steps and cost. The unique process of metal spinning forms complex shapes from aluminum, steel, alloys, and other metals. Rotating a disc or tube of metal at high speeds produces axially symmetric parts and improves the tensile strength of the metal. Metal die-casting produces parts that have high heat resistance, high strength and stiffness, and low thermal expansion qualities.

In contrast, thermoforming provides higher rates of production with a level of detail and complexity that greatly exceeds the capabilities of metal processes. For example, the application of plastic thermoformed enclosures, housings, and covers for medical diagnostic equipment shortens the development and production cycles. Moreover, the use of thermoformed materials establishes lower cost tooling for applications that must comply with global safety standards.

Weight Considerations – Plastic Thermoforming vs. Metal

Plastic thermoforming allows manufacturers to use materials that have a lower density and thinner walls. Both qualities allow weight-conscious industries such as automotive and aerospace manufacturing to achieve significant weight reduction while retaining strength and durability. The use of thermoplastics improves fuel economy and reduces emissions with decreased weight and lowered friction losses in the powertrain. Reducing the weight of gears causes a reduction in inertia and an increase in automotive efficiency. The use of thermoplastics also reduces noise and vibration levels.

For electrical components, the capability to produce strong, lightweight parts also promotes the production of lightweight, wall-mounted or pole-mounted enclosures. Using thermoformed plastics for the electrical enclosures allows easier lifting than seen with aluminum or steel enclosures. When comparing the weights of thermoformed objects to metal objects, noticeable differences exist. With two same-sized objects constructed from polycarbonate and fiberglass, the polycarbonate object weighs approximately ½ pound less. An aluminum same-sized object will weigh twice the amount, an object made from steel will weigh more than six times as much.

The following chart depicts the differences in specific gravity density for different types of thermoplastic and metal materials. Specific gravity equals the ratio of density of the material to the density of water at 39°F. Because the thermoplastics shown in the chart have superior strength-to-weight ratios than the metals, the lighter thermoplastics have equivalent strength and stiffness.

MaterialSpecific Gravity
High-impact ABS1.03
Acetal copolymer1.41
Aluminum2.55 – 2.80
Cast Iron7.03 – 7.13
Cast Rolled Brass8.4 – 8.7
Stainless Steel7.7
Carbon Steel7.8
Tool Steel7.70 – 7.73
Tungsten Carbide14.29


Durability Comparisons – Plastic Thermoforming vs. Metal Manufacturing

Polycarbonate has become a popular alternative for enclosures because of its strength and durability. The durability and impact resistance of polycarbonate allows the use of enclosures in all types of weather and environmental conditions in industries such as oil exploration, agricultural irrigation, wind turbines, and maritime. A polycarbonate enclosure has a tensile strength of 900 pounds per square inch and has a high impact resistance. In addition, polycarbonate enclosures resist damage caused by ultraviolet rays and have high NEMA ratings for dust and moisture protection.

Time and Cost Savings Achieved with Thermoplastics

Medical Device with plastic thermoformed enclosure

Medical device enclosure manufactured and assembled from multiple plastic thermoformed parts

While a stainless steel enclosure offers the same resistance, stainless steel costs three times more than polycarbonate. The cost comparison between thermoplastics and metals goes beyond direct monetary costs and includes indirect costs such as time. Again, using polycarbonate enclosures as an example, thermoplastics offer the advantage of easy modification. Machining a stainless-steel enclosure requires special tools and additional time.

The weight reduction seen with a polycarbonate enclosure also factors into time and cost savings. Rather than requiring two installers for the attachment of an outdoor stainless steel enclosure, the installation of a polycarbonate enclosure requires only one installer. In addition, the shipping costs for lighter weight polycarbonate enclosures are lower than the shipping costs for metal enclosures.

Direct cost savings with thermoplastics occur through repeatable manufacturing processes that produce less scrap. Given the durability of thermoplastic materials, tools and parts have a much longer service life. Manufacturing costs also decrease because of the design flexibility to consolidate parts and to produce complex mechanisms without secondary processes. Because of the numerous thermoplastic options, manufactures can carefully select materials that optimize manufacturing to production ratios and reduce lead times.


Thermoplastics have replaced the use of carbon steel, stainless steel, titanium, aluminum, magnesium, brass, and bronze in many industrial applications. Along with weight reduction, thermoplastics offer enhanced performance, greater design freedom, and decreased total system costs. Enhanced performance occurs through corrosion resistance, lower friction, increased fuel efficiency, and the capability to handle large loads at higher speeds in harsh environments.

Thermoplastics have become standard materials for parts such as medical diagnostics equipment components, enclosures, fender wells, rear bumpers, seating and interior trim components, window masks, wall paneling, decorative signs, and construction cab interiors.  Heavy gauge thermoforming eases the process of manufacturing those components by forming a two-dimensional rigid sheet of thermoplastic into a three-dimensional shape that fits industrial needs and standards.  Intricate designs with molded colors and textures occur at lower costs and with faster production cycles.


Productive Plastics is top contract manufacturer for heavy gauge thermoforming, including vacuum forming and pressure forming. Contact us or request our complimentary thermoforming design guide for more information.

Please contact Productive Plastics for more information on the thermoforming process
Please download our complimentary thermoforming design guide for more information on the thermoforming process


Manufacturing the Right Team to Better Serve You

I am pleased to announce the addition of Carl Foehner Associates to the sales team at Productive Plastics.

Carl has over 40 years of experience in the plastics industry, with the greater part of his career invested in engineering sales and supporting thermoforming technology. His diverse experience in disciplines paramount to our industry enable Carl to provide insight and guidance to customers during the entire development process; from product design to final production.

Carl will be working closely with our VP of Sales, John Zerillo and the rest of the Productive Plastics team to bring our customers the highest level of service, quality manufacturing, product development, and rapid solutions for the production of custom plastic thermoformed components.

I invite you to connect with Carl to discuss how Productive Plastics can contribute to your project’s success.


Evan Gilham

COO | Productive Plastics

Carl Foehner | Carl Foehner Associates

Office 973-506-7091

Mobile 201-220-1207

Productive Plastics

103 West Park Dr. Mt. Laurel, NJ 08054

Office (856) 778-4300

Productive Plastics is top contract manufacturer for heavy gauge thermoforming, including vacuum forming and pressure forming. Contact us or request our complimentary thermoforming design guide for more information.

Please contact Productive Plastics for more information on the thermoforming process
Please download our complimentary thermoforming design guide for more information on the thermoforming process