TPI
Two-Shot Injection Molding for Tier 1 Automotive & High-Volume Manufacturers
Our two-shot injection molding company is IATF 16949-certified with 38 presses from 85T to 1,630T, specializing in two-shot, insert, and overmolding for automotive OEMs, Tier 1 suppliers, and other high-volume manufacturers across North America. We engage at the design stage, not just the quoting stage.
Engineered Plastics
Two-Shot Injection Molding
TPI
Two-Shot Expertise
For Engineering Teams
Our engineers engage at the concept stage to help prevent rework and the launch delays that go with it. We provide DFM input, flag material compatibility concerns, and conduct Moldflow analysis to validate gate locations and predict weld line behavior.
For Purchasing / Sourcing Teams
We bring the program management structure you need: milestone-driven PPAP planning, transparent capacity commitments, IATF 16949 certification, and a track record with Tier 1 customers including Magna, L&L Products, Lear, and Aisin.
Above and Beyond Two-Shot
RAPID PROTOTYPING
Make informed decisions before full-scale production with our rapid prototyping capabilities. We evaluate the design and identify potential issues quickly and cost-effectively to speed up the product development process.
INSERT & OVERMOLDING
Our specialized press-to-press transfer technique allows us to mold 360-degrees. It’s ideal when your application requires molding over metal inserts such as fasteners and magnets or other substrates such as structural reinforcements.
COLOR MATCHING
We’ve worked with hundreds of materials and additives, so we can accurately predict how processing will affect appearance. This expertise allows for precise color-matching and replication of design intent, enhancing visual appeal and brand identity.
APPLICATIONS
MANUFACTURING CAPABILITIES
Our expertise lies in two-shot overmolding and insert molding. We also design and build trim tooling, end-of-arm tooling (EOAT), assembly fixtures, and quality gauges in-house. All of this is complemented with high levels of automation.
DESIGN & ENGINEERING
Our design and engineering team has the experience to take full design responsibility or serve as a design partner. Our product development services include design for manufacturability (DFM), material compatibility analysis, Moldflow simulation, mold design, and rapid prototyping.
MATERIALS
There are hundreds of materials suitable for two-shot and thousands of ways to fine-tune them. Our material experts have validated combinations across PP, nylon, TPO, TPE, TPV, and TPR, and our in-house testing lab confirms material compatibility before production commitment.
Trusted by Tier 1 Automotive Suppliers and Industrial OEMs
9 out of 10 of our largest customers purchase from two or more of our processes.
Trusted by Tier 1 Automotive Suppliers and Industrial OEMs
9 out of 10 of our largest customers purchase from two or more of our processes.
Ready to run a part?
For Engineering Teams
Start with a DFM conversation. Share your part design or concept — our engineers will give you an honest assessment of moldability, material options, and what tooling approach makes sense. No RFQ required to have that conversation.
For Purchasing / Sourcing Teams
We’re ready to respond to your RFQ with total program cost (piece price + tooling + logistics), a milestone-driven PPAP schedule, and capacity confirmation. We can also provide certification documents, customer references, and a completed supplier questionnaire.
TWO-SHOT INJECTION MOLDING FAQS
About Two-Shot Injection Molding
What is two-shot injection molding?
Two-shot injection molding (also called 2K molding or multi-shot molding) is a process that molds two different plastic materials or two colors of the same material in a single production cycle. The result is a single, bonded part that would otherwise require secondary assembly.
Benefits include lower total program cost, improved dimensional consistency, and the ability to integrate multiple functions (sealing, soft-touch, structural) into one component.
When does two-shot make sense versus single-shot plus assembly?
Two-shot is most cost-effective for high-volume programs where the tooling investment is amortized across large quantities, and where the part design genuinely benefits from integrating two materials such as a rigid structural substrate with a soft-touch or sealing overmold.
Our engineers can model the total cost comparison (piece price + tooling + assembly labor eliminated) for your specific program.
Request a DFM conversation.
What is the difference between robotic transfer two-shot and robotic platen (integrated) two-shot?
Robotic transfer two-shot uses a robot to move the substrate between two separate presses. Integrated two-shot uses a rotary platen inside a single machine to index the substrate into position for the second injection.
The right approach depends on part geometry, required tonnage, and cycle time targets. We run both and will recommend the appropriate process for your design.
What materials are best for two-shot injection molding?
The two-shot injection molding process combines two different plastic resins in one machining cycle. To realize the full benefits of this process, you should choose two compatible materials that can form a molecular bond while simultaneously meeting the functional requirements of your part. Learn about the most common two-shot injection molding materials in our Two-Shot Design Guide, or contact us if you need help choosing compatible materials.
What design considerations should be made for the two-shot injection molding process?
Two-shot injection molding is the ideal process for complex parts. As such, part design often requires a high level of refinement and sophistication. That’s why we’ve developed a Two Shot Design Guide. It provides the foundation you’ll need to start designing for the two-shot molding process.
How much does two-shot injection molding cost?
Two-shot injection molding eliminates the need for secondary processes such as welding and assembly. As such, piece prices tend to be lower for two-shot molded parts compared to multi-component single-shot assemblies. The tooling for two-shot, on the other hand, tends to be more complex and costly than single-shot. Therefore, two-shot injection molding is most cost-efficient for high-volume productions. Request a quote today to see if two-shot molding is the right solution for you.
About Working with Us
What size programs do you typically support?
We work primarily with programs producing a minimum of 10,000 parts annually with an annual buy over $100,000. Our press range (85T–1,630T) accommodates a wide range of part sizes and complexity levels.
Who are some of your customers?
Our automotive customer base includes Tier 1 suppliers such as Magna, Lear, Forvia, Adient, and Toyoda Gosei, supporting programs for Ford, GM, Stellantis, Rivian, Honda, Toyota, Nissan, and Volkswagen.
We also supply industrial and lawn & garden manufacturers including John Deere, Stanley Black & Decker, Atlas Copco, and Milwaukee Tool.
What certifications do you hold?
Our two-shot injection molding company is certified to IATF 16949:2016 (automotive quality management system) and ISO 14001:2015 (environmental management system), and is a WBENC-certified Women's Business Enterprise.
What materials do you work with?
Our engineers have validated hundreds of material combinations across the following:
- Polypropylene (PP)
- Nylon (PA)
- Glass Filled
- Talc Filled
- Fiber Reinforced (LFR, SFR)
- Thermal Expanding Resin
- Polyethylene (HDPE, MDPE, LDPE)
- TPO
- TPV (Santoprene)
- PVC (Rigid & Flexible)
- ABS
- Polystyrene (PS)
- Acrylic
- Class A – Color Matched
- Graining
What are your capabilities?
- Two-shot injection molding
- Multi-shot injection molding
- Insert and overmolding
- Secondary operations
- Welding (infrared, hot plate, ultrasonic)
- Riveting and staking
- Hot stamping
- Foam and acoustic pad assembly
- Part identification marking
- Parts kitting
- In-house tooling design and build
- Injection mold
- Trim/fabrication tooling
- Assembly fixtures
- Quality gauges
- Advanced testing laboratory
- PPAP
- Material property analysis
- Mechanical testing
- Rapid prototyping
- Specialized engineers and designers
- Dedicated prototyping presses
- Advanced software and technology
- Prototype molds made from wood, epoxy, aluminum, or steel
Do you offer molding options other than two-shot injection molding?
Two-shot injection molding is just one of our many plastic molding capabilities. We also specialize in:
- Profile extrusion
- Technical blow molding
- Compression molding (including Baypreg and Azdel)
This breadth of experience enables us to evaluate multiple processes and materials and recommend the optimal combination for your unique application.
In fact, 9 out of 10 of our largest customers purchase products from two or more of our processes.
Who manufactures your tooling?
We design and manufacture most trim and fabrication tooling, as well as assembly fixtures, in-house. We’ll occasionally build prototype and production molds in-house, but we’ve found it’s usually more cost-effective to design in-house and partner with a dedicated, US-based moldmaker for the manufacturing.
How do I submit an NDA with my quote request?
You can attach your NDA to our RFQ form or send it directly to plasticsales@geminigroup.net.
How do I contact you? Where are you located?
Our two-shot injection molding company is located in Bad Axe, Michigan, in the heart of the Great Lakes automotive supply region. As part of Gemini Group, we have 17 locations across North America. You can drop us a note online, give us a call at 989-269-9791 or email us at plasticsales@geminigroup.net.
Wherever You’re Located, We’re Here to Help
17 strategic locations in North America to meet the needs of our diverse customer base.
Two-Shot Molding Design Guide
Two-shot design can deliver a competitive advantage far above other molding processes, especially for complex parts. Learn the benefits of the process and explore the special design requirements needed to make it work in this free guide created by engineers, for engineers.
Insights
Get to know us. Get in touch today.
We have the resources to meet any part or production challenge. Let’s talk about what that means for you.
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