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Injection Molding Service | Stratasys Direct

Injection Molding Service

Expert Injection Molding for High-Quality, Durable Parts – Every Time

ISO9001 & AS9100 QMS | DDTC/ITAR Registered

Injection Molding

Injection Molding (IM) Manufacturing Service

Injection molded part exploded view Stratasys Direct

What Is Injection Molding?

Injection molding is the most commonly used method for producing higher volumes of plastic parts. Simply put, it is the process by which plastic or rubber materials are heated above their melting point and injected into a mold to create the desired shape. The part is cooled, then ejected from the mold, and secondary operations are performed such as the removal of flashing (excess material on the part). 

Injection molding takes place when a thermoplastic or thermoset plastic material is fed into a heated barrel, mixed, and forced into the metal mold cavity where it cools and hardens before being removed.

Mold and die are used interchangeably to describe the tooling applied to produce plastic parts. They are typically constructed from pre-hardened steel, hardened steel, aluminum, and/or beryllium-copper alloy. Of these materials, hardened steel molds are the most expensive to make, but offer the user a long lifespan, which offsets the cost per part by spreading it over a larger quantity.

For low volumes or large components, pre-hardened steel molds provide a less wear-resistant and less expensive option. The most economical molds are produced out of aluminum. When designed and built using CNC machines or Electrical Discharge Machining processes, these molds can economically produce tens of thousands to hundreds of thousands of parts. Note that beryllium copper is often used in areas of the mold that require fast heat removal or places that see the most shear heat generated.

The injection molding process uses a granular plastic that is gravity fed from a hopper. A screw-type plunger forces the material into a heated chamber, called a barrel, where it is melted. The plunger continues to advance, pushing the polymer through a nozzle at the end of the barrel that is pressed against the mold. The plastic enters the mold cavity through a gate and runner system. After the cavity is filled, a holding pressure is maintained to compensate for material shrinkage as it cools.

At this same time, the screw turns so that the next shot is moved into a ready position, and the barrel retracts as the next shot is heated. Because the mold is kept cold, the plastic solidifies soon after the mold is filled. Once the part inside the mold cools completely, the mold opens, and the part is ejected. The next injection molding cycle starts the moment the mold closes and the polymer is injected into the mold cavity.

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Handpiece Injection mold

Injection Molding Solutions Across Product Development

3D printing is commonly used for quick iterations, design verification, and even for end-use part production when going into preproduction, early market introduction, and supply chain.

At our state-of-the-art facilities, we are able to provide end-to-end product development life cycle solutions in a wide range of technologies and materials but after a certain point Injection molding is an ideal alternative to 3D printing for parts at a better cost per piece and in materials not available in 3D printing.


Domestic & Offshore Production 

At Stratasys Direct we employ both domestic and offshore production with US-based project management and quality assurance for efficient, cost-effective tooling and injection molding operations.

Whether you need low-volume parts quickly or high-volume production our experienced team is dedicated to delivering your parts on your timeline. 

Our U.S.-based injection molding project management team provides a mold-build schedule, regular project updates, and timely production with globally competitive pricing.

Injection Molding Benefits

Large Volumes

Large volumes

Produce high volumes of consistent production parts with near-limitless plastic material options.

Rapid Delivery

Rapid delivery

Our proprietary tooling methods allow us to deliver low-volumes of parts two weeks.

Quality Production Parts

Quality production parts

Get precise, repeatable parts throughout large production at the quality you expect.

Injection Molding Materials

SDM Material


Common thermoplastic with good impact resistance and toughness.

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SDM Material


Thermoplastic polymer used for a wide number of applications.

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SDM Material

Polyoxymethylene (POM)

Dimensionally stable thermoplastic with high stiffness and low friction.

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SDM Material


Thermoplastic material with good temperature resistance and impact strength.

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SDM Material

Polycarbonate / ABS

Blend of PC and ABS that creates strong parts for a variety of applications.

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SDM Material


PVC is a polymer with good insulation properties, high hardness, and good mechanical properties.

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SDM Material


Polymer material that is durable with high elongation and good abrasion resistance.

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SDM Material

Nylon 32% Glass Fiber

Polymer with excellent mechanical stiffness and elevated temperature resistance.

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SDM Material

Acrylic (PMMA)

Material with resistance to breakage often used for transparent applications.

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SDM Material


Light weight material popular for its high impact strength and toughness.

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SDM Material

Polyetherimide (PEI)

Thermoplastic with high heat resistance and excellent mechanical properties.

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injection molded skis

Injection Molding Quality Assurance

Injection molding precise parts takes a team of experts, ensuring well-built tooling and smooth processes offshore and onshore.

Working with customers across a variety of industries, we’ve developed thorough methods to provide solutions for tooling and complementary post-processing in order to serve your versatile needs.

With ISO 9001 quality certifications, our team of experts won’t rest until your requirements for precise parts are met.

General questions? Engineering questions? Need help with your design?

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injection molded plastic part

Frequently Asked Questions About Injection Molding


Is injection molding expensive?  

The creation of the mold tool and tool verification is likely to be the most expensive part of the process, but IM is cost-effective for large part runs. The cost of injection molding is influenced by the size, material used, the intricacy of the design, and the number of parts being produced. 

Injection Mold tolerance?

We can meet industry standard tolerances of +/- 0.005”. We can achieve tighter tolerances in some instances depending on part geometry and material.

Where is the project management team located?

Our experienced Tooling and Injection Molding management team is based out of Phoenix, Arizona. They have a deep understanding of all phases of tooling, including part design, tool design, and material sciences.

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