Plastic Injection Molding
Get custom plastic molded prototypes and production parts in as few as 10 business days. We provide expert engineering reviews and $500 off your first mold. Dozens of materials and finishes are available.
What Is Injection Molding?
Injection molding is the most cost-effective way to make a plastic part at scale. The process involves injecting molten plastic into a mold tool, then ejecting the solidified part. This process quickly repeats hundreds or thousands of times, amortizing the cost of the mold tool and driving down the cost of each unit to a few dollars or less. Since injection molding uses the same mold tool for each part, the process offers consistent quality across every part. Injection molding also has the highest variety of materials, colors, cosmetics, polishes, and surface textures when compared to CNC machining or even 3D printing.
Xometry's injection molding service is a highly customized service providing on-demand prototype and production molding. We take a customer-first approach which means we find the right injection molding supplier within our manufacturing supplier network to mold the parts the way you need them—without design compromises—at the right price point. We offer expert consultation on each injection mold quote and project managers on every order to move your parts from design to production. Our team has experience in every industry, especially medical injection molding and liquid silicone rubber molding. First-time buyers receive $500 off their first mold with Xometry. We offer both domestic and China injection molding options, as well as ITAR injection molding.
Injection Molding Capabilities
| Service | Details |
|---|---|
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Service
Lead Time |
Details
Starts at 10 business days, including 24-hour quote responses with design-for-manufacturing (DFM) feedback |
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Service
Production Options |
Details
Domestic and international |
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Service
Materials |
Details
Most plastics, including custom sourcing and matching; see materials list below |
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Service
Machines Available |
Details
Single, multi-cavity, and family molds; 50 to 1,100+ press tonnage; side actions including hand-loaded cores |
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Service
Inspection and Certification Options |
Details
Includes FAI and PPAP. ISO 9001, AS9100, ISO 13485, UL, ITAR, and ISO 7 and 8 Medical Clean Room molding. |
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Service
Tool Ownership |
Details
Customer-owned with mold maintenance |
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Service
Mold Cavity Tolerances |
Details
+/- 0.005" when machining the mold and an additional +/- 0.002" per inch when calculating for shrink rate |
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Service
Part to Part Repeatability |
Details
+/- 0.004" or less |
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Service
Critical Feature Tolerances |
Details
Tighter tolerances can be requested and may increase the cost of tooling because of additional sampling and grooming. Xometry will mill to a steel-safe condition on critical features. |
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Service
Available Mold Types |
Details
Steel and aluminum; Production grades range from Class 105, a prototype mold, to Class 101, an extremely high production mold. Xometry typically produces Class 104, 103, and 102 tools. |
This table depicts the general tolerances for Xometry’s injection molding services and accounts for adequate draft, radii, and coring for manufacturability. Learn more about our injection molding manufacturing standards.
| Class 105 | Class 104 | Class 103 | Class 102 | Class 101 |
|---|---|---|---|---|
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Class 105
Under 500 cycles. Prototype only. This mold will be constructed in the least expensive manner possible to produce a very limited quantity of prototype parts. Also known as a Class V tool. |
Class 104
Under 100,000 cycles. Low production mold. Use only for limited production preferably with non-abrasive materials. Low to moderate price range. Also known as a Class IV tool. |
Class 103
Under 500,000 cycles. Medium production mold. This is a very popular mold for low to medium production needs. Most common price range. Also known as a Class III tool. |
Class 102
Medium to high production, good for abrasive materials and/or parts requiring close tolerance. This is a high-quality, fairly high-priced mold. Also known as a Class II tool. |
Class 101
Over 1,000,000 cycles. Built for extremely high production. This is the highest-priced mold and is made with only the highest quality materials. Also known as a Class I tool. |
Additional Molding Options Available at Xometry
Insert Molding Service
Overmolding Service
Metal Injection Molding (MIM) Service
Medical Injection Molding
Gas Assist Injection Molding
Injection Molding in China
Liquid Silicone Rubber Molding
Large Part Injection Molding Services
How Custom Plastic Injection Molding Works
The process of plastic injection molding requires an injection molding machine, raw plastic material, and a machined mold. The raw plastic material is first melted in the injection unit and is then injected into the mold—most often machined from steel or aluminum—where it cools and solidifies into the final plastic part.
At Xometry, we first review your injection molding online quote, then consult with you to ensure your specifications, lead time, and price fit your project needs. We then use your 3D part data to CNC machine a high-quality injection mold. Once the mold is created, Xometry sends ten part samples (T1) for approval. Once the mold is refined and approved, Xometry begins production. Xometry molds a variety of products and parts from the smallest medical insert up to large automotive, aerospace, and defense parts.
Plastic Injection Molding Materials
| Rigid And Flexible Resins |
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Rigid And Flexible Resins
ABS | Acrylonitrile Butadiene Styrene |
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Rigid And Flexible Resins
ASA | Acrylonitrile Styrene Acrylate |
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Rigid And Flexible Resins
CA | Cellulose Acetate |
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Rigid And Flexible Resins
COPO | Copolyester |
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Rigid And Flexible Resins
HDPE | High-Density Polyethylene |
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Rigid And Flexible Resins
LCP | Liquid Crystal Polymer |
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Rigid And Flexible Resins
LDPE | Low-Density Polyethylene |
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Rigid And Flexible Resins
PA 6 | Polyamide 6, Nylon 6 |
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Rigid And Flexible Resins
PA 6/6 | Polyamide 6/6, Nylon 6/6 |
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Rigid And Flexible Resins
PARA | Polyaryl Amide |
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Rigid And Flexible Resins
PBT | Polybutylene Terephthalate, Valox |
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Rigid And Flexible Resins
PBT-PET | Polybutylene Terephthalate-Polyethylene Terephthalate |
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Rigid And Flexible Resins
PC | Polycarbonate |
Learn more about our molding materials.
Elastomers and Synthetic Rubbers for Molding
| Elastomers and Rubber-Like Materials |
|---|
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Elastomers and Rubber-Like Materials
EPDM | Ethylene Propylene Diene Monomer Rubber, Viton |
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Elastomers and Rubber-Like Materials
MPR | Melt Processable Rubber |
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Elastomers and Rubber-Like Materials
POE | Polyolefin Elastomer |
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Elastomers and Rubber-Like Materials
PVC | Polyvinyl Chloride (Shore A) |
Check out more information our materials here.
Custom Sourced Materials
If you do not see the material stock you are looking for, please choose "Custom" under the material drop-down on your online quote page and submit it for an expert engineering review once you have specified features, tolerances, inspection needs, and quantities required. Xometry can also use customer-sourced or customer-supplied resin for production projects.
Moldmaker's choice of finish. Typically SPI B-2, depending on geometry and drafts. Interior, non-cosmetic faces, are typically as-machined.
Range of Society of Plastics Industry (SPI) finishes from Grade 3 diamond / high polish to 320 stone low polish. Finishes include: SPI A-1, SPI A-2, SPI A-3, SPI B-1, SPI B-2, SPI B-3, SPI C-1, SPI C-2, SPI C-3, SPI D-1, SPI D-2, and SPI D-3
Range of finishes including matte, swirls, lines, and patterns. Our most common texture finishes include: MoldTech MT11010, MoldTech MT11020, and MoldTech MT11030. Other textured finishes can be added by request.
VDI 3400 Surface Finish (commonly known as VDI surface finish) refers to the mold texture standard set by Verein Deutscher Ingenieure (VDI), the Society of German Engineers. This is mainly processed by EDM machining, producing fine to coarse matte finishes.
No secondary polishing or grinding. Part will show tooling marks.
We can install most commonly used standard inserts in UNF and metric sizes.
Transfer a 2D image onto a 3D part. All images are subject to review.
Engrave part numbers, logos, and more onto your parts.
Xometry has the ability to assemble and label molded parts. Discuss your needs with your salesperson.
A guide to injection molding finishes
An Overview of Injection Molded Surface Finishes
Video: 7 Ways to Save on Injection Molding
Injection Molding Design Guidelines
| Feature | Tip |
|---|---|
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Feature
Undercuts |
Tip
Reduce undercuts, which will increase the complexity and cost of the tool ejection mechanisms, by adding in pass-thru coring. |
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Feature
Wall Thickness |
Tip
Prevent wall sink and voids by maintaining an even wall thickness. Thinner walls reduce cycle time and reduce costs. |
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Feature
Drafts |
Tip
Ensure parts are designed with a minimum draft angle of 0.5°, or up to 5°, for faces with medium textures. |
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Feature
Ribs/Gussets |
Tip
Ribs should be 40-60% the thickness of outer walls and should still maintain draft. |
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Feature
Bosses |
Tip
Bosses should be designed at a depth of 30% the wall thickness and with a 30% edge groove. Attach them to side walls or ribs for structural integrity. |
To see these design-for-manufacturing recommendations in detail, view our Injection Molding Design Guide.
Ready to Get a Custom Injection Molding Quote?
Applications and Advantages of Injection Molding
Low-cost tooling allows molded parts to be produced in as fast as 10 business days at affordable prices.
Molding can be the ideal process for low-volume production molding of 250 units to mass production molding of over 1,000,000 units. Molded parts will generally perform better than the same part CNC machined or 3D printed using the same material. Careful selection of the resins allow for a wide range of properties and solvent compatibility. Molds are CNC machined to high precision, high tolerances and are able to produce thousands of identical parts with very small and intricate details.
We offer ISO 9001, AS9100, ISO 13485, UL, ITAR, and ISO 7 and 8 Medical Clean Room molding.
Injection molding is used across a wide range of industries including aerospace, medical devices, consumer goods, energy, electronics, automotive, robotics, toys, and more.
With molding, plastic or metal parts are created inside a mold. They are then removed from the mold as fully-formed parts. 3D printing, on the other hand, is an additive manufacturing process, meaning that the part is built layer-by-layer using processes like deposition or sintering.
After receiving the order, the statement of work is reviewed by one of our manufacturing engineers. A case manager is assigned, and an appropriate manufacturing supplier is identified. A comprehensive DFM/PEG report is created and provided for approval. Upon approval, tooling and mold production is commenced. T1 samples are produced and shipped for approval. Upon approval, the remaining parts are made.
At Xometry, our customers own their injection mold tools! After a run is complete, the tool will remain at our facilities. Tools can be shipped to you upon request; however, you will be responsible for any associated shipping and packaging costs. Our engineers will work with you regarding tool compatibility with your equipment if you're unsure.
Yes, multiple colors can be run even on the same order! When running multiple colors on the same order, a purge charge will be added.
Why Use Xometry Injection Molding Services?
Endless Options
Choose from millions of possible combinations of materials, finishes, tolerances, markings, and certifications for your order.
Easy to Use
Get your parts delivered right to your door without the hassle of sourcing, project management, logistics, or shipping.
Vetted Network
We are ISO 9001:2015, ISO 13485, and AS9100D certified. Only the top shops that apply to become Suppliers make it through our qualification process.