Choosing the Right Finish for Your Injection Molded Parts
With the wide variety of surface finishes and treatments offered by Xometry, we've got your injection molded parts covered.
Injection Molding Service
Custom molded prototypes and production parts with fast lead times
High Quality Custom Plastic Injection Molding
Xometry delivers high-quality, on-demand injection molded parts. Injection molding is the most cost-effective way to make a plastic part at scale and offers consistent quality for low-to-high volume manufacturing. Molding also has the highest variety of materials, colors, and configurations when compared to CNC machining or even 3D printing. Beyond materials, injection molded parts can have custom cosmetics, polishes, or surface textures.
Xometry takes a “have it your way” approach to molding. We specialize in complex projects, including those requiring side action or hand loaded inserts. Our goal is to provide a long-term solution, moving beyond rapid prototyping, with dedicated project managers and engineering experts to communicate through all project stages from design to production.
Xometry’s injection molding services include:
- Free online file upload and quote submission
- 24-hour quoting with design for manufacturing (DFM) feedback
- Large domestic partner network as well as international options
- Single point of contact per customer
- Expert consultation
- Single, multi-cavity, and family mold options
- Insert molding and overmolding
- Most plastic materials, including custom sourcing and matching
- Press availability from 50 to 1,100+ tons
- Part inspection, including FAI and PPAP options
- Customer-owned tooling
- Learn about our Injection Molding capabilities for the Medical Devices industry
Is your project ready for injection molding? Upload your 3D model for a free quote.
Advantages of Injection Molding
Scalability
Molding can be the ideal process for custom production runs of 250-25,000+ parts.
Rapid Turnaround
Using our vetted Partner Network, Xometry is able to produce top quality Molded parts in as little as 10 business days.
Efficiency
In higher volumes, custom molding with Xometry produces significantly less waste than other manufacturing processes.
Part Production
Piece price is significantly lower with Molding vs other processes, particularly as production quantities increase into the thousands.
Strength
Molded parts will generally perform better than the same part CNC Machined from the same material. Careful selection of the resins allow for a wide range of corrosion resistance and chemical and solvent compatibility.
Precision
Molds are CNC machined to high precision, high tolerances and are able to produce thousands of identical parts with very small and intricate details.
Injection Molding Processes
Thermoplastic Injection Molding
Xometry delivers top quality plastic injection molded parts in as little as 10 business days. Our Manufacturing Partner Network can help you design and manufacture tools, dies, and molds for rapid tooling for prototyping to advanced mold making for production runs. Full injection molding capabilities including insert molding, overmolding, unlimited undercuts, and internal/external threads are available.
Mold Making
Our vetted network of partners allow us to quickly convert your 3D part data into a high-quality injection mold at top speed. We offer services from design and manufacturing for tools, dies, and molds for prototyping and production runs. Plastic blow molds, aluminum and steel tooling, 2-shot and 3-shot molding are also available. And with Xometry, you own your own tools, so our partner network also offers mold maintenance services.
Overmolding
Our network is skilled at overmolding. With overmolding, one material, usually a thermoplastic elastomer (TPE/TPV), is molded onto a second material, which is often a rigid plastic. Think about your toothbrush handle where the single piece has both rigid and rubbery components. It’s a great way to make plastic parts perform and look better.
Insert Molding
Xometry now also offers insert molding as part of its injection molding capabilities. We can even use our CNC machining services to produce custom metal and plastic inserts to integrate into the part. For a free insert molding design review and quote, upload your CAD files. Our expert team of injection molders will get back to you within 24 hours.
Injection Molding Materials
Rigid and flexible plastic varieties (Custom resin matching available):
- ABS | Acrylonitrile Butadiene Styrene
- ASA | Acrylonitrile Styrene Acrylate
- CA | Cellulose Acetate
- COPO | Copolyester
- HDPE | High-Density Polyethylene
- LCP | Liquid Crystal Polymer
- LDPE | Low-Density Polyethylene
- PA 6 | Polyamide 6, Nylon 6
- PA 6/6 | Polyamide 6/6, Nylon 6/6
- PARA | Polyaryl Amide
- PBT | Polybutylene Terephthalate, Valox
- PBT-PET | Polybutylene Terephthalate-Polyethylene Terephthalate
- PC | Polycarbonate
- PC-ABS | Polycarbonate-Acrylonitrile Butadiene Styrene
- PC-PBT | Polycarbonate-Polybutylene Terephthalate, Xenoy
- PC-PET | Polycarbonate-Polyethylene Terephthalate
- PCT | Polycyclohexylenedimethylene Terephthalate
- PE | Polyethylene
- PE-PP | Polyethylene-Polypropylene
- PE-PS | Polyethylene-Polystyrene
- PEBA | Polyether Block Amide
- PEEK | Polyether Ether Ketone
- PEI | Polyetherimide, Ultem
- PES | Polyether Sulfone
- PET | Polyethylene Terephthalate, Rynite
- PLA | Polylactic Acid
- PMMA | Polymethyl Methacrylate, Acrylic
- POM | Acetal Polyoxymethylene, Delrin
- PP | Polypropylene
- PPA | Polyphthalamide
- PPS | Polyphenylene Sulfide, Ryton
- PS | Polystyrene
- PS-PPE | Polystyrene-Polyphenyl Ethers, Noryl
- PSU | Polysulfone, Udel
- PVC | Polyvinyl Chloride (Shore D)
- PVDF | Polyvinylidene Fluoride
- SAN | Styrene Acrylonitrile
- TPO | Thermoplastic Polyolefin
- TPU | Thermoplastic Polyurethane (Shore D)
- Custom-sourced Resin
- Customer-supplied Resin
Get an instant quote or check out more information about our rigid plastic materials.
Rubber-like varieties (Custom resin matching available):
- EPDM | Ethylene Propylene Diene Monomer Rubber, Viton
- MPR | Melt Processable Rubber
- POE | Polyolefin Elastomer
- PVC | Polyvinyl Chloride (Shore A)
- TPE | Thermoplastic Elastomer, Santoprene
- TPU | Thermoplastic Polyurethane (Shore A)
- TPV | Thermoplastics Elastomer, Vulcanized Rubber
- Custom-sourced Resin
- Customer-Supplied Resin
Get an instant quote or check out more information about our rubber-like plastic materials. Compression molding is available upon request.
Silicone materials:
- LSR | Liquid Silicone Rubber
Get an instant quote or check out more information about our rubber-like plastic materials.
Injection Molding Finishes
Standard Finish
Moldmaker's choice of finish. Typically SPI B-3 to D-3 depending on geometry and drafts. Interior, non-cosmetic faces, are typically as-machined.
SPI A-1
Grade #3 Diamond. Typical Application: High polish parts, optically clear.
SPI A-2
Grade #6 Diamond. Typical Application: High polish parts.
SPI A-3
Grade #15 Diamond. Typical Application: High polish parts.
SPI B-1
600 Grit Paper. Typical Application: Medium polish parts.
SPI B-2
400 Grit Paper. Typical Application: Medium polish parts.
SPI B-3
320 Grit Paper. Typical Application: Medium- Low polish parts.
SPI C-1
600 Stone. Typical Application: Low polish parts.
SPI C-2
400 Stone. Typical Application: Low polish parts.
SPI C-3
320 Stone. Typical Application: Low polish parts.
SPI D-1
Dry Blast Glass Bead. Typical Application: Satin Finish
SPI D-2
Dry Blast #240 Oxide. Typical Application: Dull Finish
SPI D-3
Dry Blast #24 Oxide. Typical Application: Dull Finish
As-Machined
No secondary polishing or grinding. Part will show tooling marks.
MoldTech - MT11010
Matte surface textures that are more coarse than SPI D-3.
MoldTech - MT11020
Matte surface textures that are more coarse than SPI D-3.
MoldTech - MT11030
Matte surface textures that are more coarse than SPI D-3.
MoldTech - MT112XX
A variety of almost leather-like texture options. Common for automotive interiors. Please specify which texture is required before submitting the project.
MoldTech - MT114XX
A variety of textures from lines, to swirls, to wood grain. Please specify which texture is required before submitting the project.
MoldTech - MT116XX
Pattern-style textures such as diamond, circular, or square grids. Please specify which texture is required before submitting the project.
Other Mold Texturing
Xometry can match other mold textures upon request.
Applications for Injection Molding
Rapid Prototyping
Although molding is best suited for medium to high volumes, the use of low cost tooling allows molded parts to be produced very rapidly and cost effectively. In almost every case, a molded part will outperform the same 3D printed or machined part from the same material. And depending on the part geometries and the material selected, low cost tooling can last for many tens of thousands of parts.
End-Use Production
Molding is best known for producing production parts in the many thousands or even millions. With the advent of newer higher strength materials and fillers such as glass and carbon fiber, parts previously made out of metal are being replaced wit molded parts to save weight and fight corrosion.
Certifications
ISO 9001, ISO 13485, UL, ITAR, ISO 7 & 8 Medical Clean Room (contact us)
Overview: What is Injection Molding?
The Basics of Injection Molding
Injection molding is one of the most often-used manufacturing processes for creating plastic parts. Thanks to its high-precision, repeatability, and cost efficiency at scale, injection molding is used to make a variety of products and parts from the smallest medical insert up to large automotive & Aerospace and Defense parts.
How Injection Molding Works
The injection molding process 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.
The key steps in the injection molding process are:
- Clamping: The two sides of the mold are closed and clamped shut.
- Injection: The material is fed into the machine and pushed towards the mold. While this is happening, the material is melted by heat and pressure. The plastic is then injected into the mold — this is called the “shot.”
- Cooling: The plastic in the mold cools and solidifies into the shape of the part.
- Ejection: After the part cools, it is ejected from the mold.
Benefits of Injection Molding
Custom injection molding offers a number of benefits not found in other manufacturing processes. Due to the high-pressure nature of the injection molding process, it is much easier to manufacture parts with detailed features or complex geometries that would be too costly for typical CNC machining processes. The ability to use your mold over and over again for a long period of time leads to an extremely high production output rate which is more cost effective and efficient than other manufacturing processes. Lastly, different injection molding processes, such as overmolding and insert molding, allow you to create plastic parts with unique characteristics such as enhanced strength, soft-grip surfaces, or added flexibility. Also beneficial is the ability to combine multiple assembly processes into one injection molding process.
Mold Class Glossary
The injection molding industry often defines molds by their class. This goes from Class 105, a prototype mold (e.g., a 100 piece one-and-done market test), to Class 101, which is built for extremely high production (e.g., making tens-of-millions contact lens cases). Xometry typically produces Class 104, 103, and 102 tools.
Name | Cycles | Description |
Class 105 | Under 500 | 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. Example: a one-and-done market test of 100 molded units. |
Class 104 | Under 100,000 | 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. Example: Aluminum or MUD tooling, SPI B-3 finish, hand-loaded cores and limited re-runs. |
Class 103 | Under 500,000 | 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. Example: Aluminum or steel tooling, automated lifts or slides, multiple re-runs with batches between 1,000-5,000 units. |
Class 102 | Under 1,000,000 | 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. Example: Steel tooling with an SPI A-2 finish, automated slides, scheduled produciton cycles. |
Class 101 | Over 1,000,000 | 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. Example: Multiple-cavity steel tooling with full automation and overnight production workcenters for dedicated part manufacturing. |
Industries that use Injection Molding
Injection Molding is used in rapid prototyping and producing pilot and high-volume production parts in a wide range of industries. It is frequently used in industries such as medical, packaging, automotive, consumer electronics, building/construction, and robotics.
Featured Injection Molding Resources
Injection Molding Design Guide
Injection molding is one of the most cost effective ways to build functional prototypes and end use parts. Learn how to design your parts for Injection Molding to ensure high quality and cost-effective results. Download your free guide today.
5 Common Mistakes For Injection Molding Part Design
Make sure you avoid these five common mistakes when designing for injection molding.
Video: 7 Ways to Save on Injection Molding
Save thousands of dollars on Injection Molding tooling using these 7 simple steps from expert Travis Minyard!
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