Custom Plastic Parts – Made Since 1993
We supply injection molded and CNC-machined plastic components to automotive, medical, electronics, and industrial equipment companies in North America, Europe, and Asia — with ISO 9001-certified production and in-house tooling.
Custom made plastic parts
Custom metal-plastic parts are widely used in many industries, such as automotive, electronics, medical, home appliances, aerospace, industrial equipment and other fields. Due to the good combination of metal and plastic, customized metal-plastic parts play an important role in improving product performance, reducing weight and reducing cost. They can be used in a variety of demanding work environments.
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Your Reliable Partner for Industrial Plastic Parts
Prime combines certified quality, deep engineering know-how, and real in-house capacity to deliver custom plastic parts that are consistent, cost-effective, and easy to source.
ISO 9001 Certified Quality
Our entire production process is ISO 9001 certified. Every batch is traced and inspected from raw material to final checks, so each part meets stringent international standards and your drawings.
30+ Years of One-Stop Experience
Since 1993, we have mastered the full chain from mold design and tooling to molding, machining and final packaging – reducing your coordination workload and communication cost.
10+ Production Lines for Speed & Flexibility
Our in-house capacity supports both prototype runs and large-volume orders, with stable lead times that keep your projects and maintenance plans on schedule.
Competitive Pricing Through Efficiency
By optimizing tooling, cycle times and our supply chain, we offer competitive B2B pricing without cutting corners on materials or quality control.
Dedicated Engineering Support
Our engineers work directly with your team on material selection, DFM, and tolerance analysis, helping you achieve reliable, cost-effective designs from the first sample.
Application fields of customized plastic parts
Here are some real-world examples of how Custom plastic Parts can be used in different industries (automotive, medical, electronics, etc.) and how Prime Custom Parts can address customer pain points.
Automotive Industry: Lightweight, Durable Components for Modern Vehicles
A leading automotive manufacturer needed custom-engineered plastic housings for their new electric vehicle platform. Their challenge was to reduce overall vehicle weight while maintaining exceptional durability and heat resistance.
Prime Custom Parts Solution:
We worked closely with their engineering team to select advanced, high-strength polymers and optimized the injection molding process to deliver precision components with tight tolerances. The result: A 20% reduction in part weight, faster assembly times, and components that passed all OEM reliability tests.
Medical Devices: Precision and Biocompatibility in Life-Critical Equipment
A medical device company required complex, biocompatible plastic enclosures for portable diagnostic equipment. Their pain points included strict compliance standards (ISO 13485) and the need for rapid prototyping to accelerate product launch.
Prime Custom Parts Solution:
Our team recommended certified medical-grade plastics and leveraged rapid tooling for fast turnaround. We ensured all parts met cleanroom manufacturing standards and delivered prototypes within two weeks—helping the client bring their device to market ahead of schedule, with full regulatory compliance.
Electronics: High-Performance Plastics for Smart Devices
An electronics OEM was developing a new generation of smart sensors for industrial automation and needed custom plastic enclosures with ESD protection and superior finish. The main challenge: combining complex geometries with EMI shielding requirements.
Prime Custom Parts Solution:
We provided material consulting, recommending conductive plastics, and integrated over-molding technology for EMI shielding. Our precision CNC machining delivered flawless, ready-to-assemble parts that improved the product’s reliability and reduced field failure rates.
Manufacturing process of main plastic parts
Metal-plastic parts can be divided into several main types according to different processes, each process has different characteristics and application fields. The following are some common metal-plastic processes and their characteristics and applications:
Injection Molding
Features:
Injection molding offers high efficiency, excellent consistency, and is ideal for producing complex, high-precision plastic parts in large volumes. It supports a wide range of materials and is widely used in automotive, electronics, medical, and consumer products.
Applications:
Injection molding is perfect for mass-producing complex plastic parts with consistent quality. It’s widely used in automotive, electronics, and medical device manufacturing.
Thermoforming
Technical Parameters:
Thermoforming typically uses plastic sheets heated to 100–200°C, then shaped over molds using vacuum or pressure, allowing for wall thicknesses from 0.25 mm to over 8 mm. It is compatible with a wide range of thermoplastics such as ABS, PET, and polycarbonate for both small and large parts.
Advantages:
Thermoforming offers fast prototyping and lower tooling costs compared to injection molding, making it ideal for moderate production runs. It enables the creation of lightweight, durable, and large-sized components with complex shapes and fine details.
Extrusion Molding
Technical Parameters:
Extrusion molding applies high pressure to force heated plastic or metal material through a shaped die, enabling continuous production of profiles with complex cross-sections. The process supports a wide range of thermoplastics, thermosets, and aluminum alloys, with output rates and tolerances determined by material type and die design.
Advantages:
Extrusion molding delivers high efficiency, low material waste, and is ideal for producing long, uniform parts with consistent cross-sections. It offers great flexibility for customizing shapes and can integrate additional features such as grooves or internal cavities.
Metal Injection Molding (MIM)
Technical parameters:
Metal Injection Molding (MIM) combines Powder metallurgy and injection molding techniques and is suitable for complex three-dimensional shapes, high precision and mass production with typical tolerances up to ± 0.3% . The process can handle iron-based, titanium alloy, stainless steel and other metal materials, commonly used in the wall thickness of 0.5 mm, the density of more than 97% of precision parts manufacturing.
Scenario:
Metal Injection Molding (MIM) is widely used in the manufacture of high-precision small structural parts in automobile, medical equipment, electronic products and aerospace industries. It is especially suitable for producing metal parts with complex shape, large batch and high requirement for mechanical properties.
Thermal Riveting
Technical Parameters:
Hot riveting typically operates at temperatures ranging from 150°C to 350°C, using controlled pressure and dwell time to securely deform and fasten thermoplastic or metal rivets. The process offers high repeatability and is suitable for a variety of part geometries and joint strengths.
Application Scenarios:
Hot riveting is widely used in automotive components, electronic housings, and household appliances for creating strong, permanent joints without adhesives or screws. It is especially suitable for mass production environments requiring rapid, automated assembly of plastic and metal parts.
Ultrasonic Welding
Technical Parameters:
Ultrasonic welding operates at frequencies typically between 20 kHz and 40 kHz, using high-frequency vibrations to generate localized heat and bond thermoplastics or metals without the need for adhesives or additional heat sources. Key parameters include amplitude, welding time, pressure, and energy, which are precisely controlled to ensure strong, clean welds with minimal material deformation.
Application Scenarios:
It is widely used for joining plastic parts in the automotive, electronics, and medical device industries, such as bonding housings, filters, and electrical connectors. Ultrasonic welding is also ideal for applications requiring clean, particle-free joints and fast, repeatable production cycles.
Compression Molding
Technical Parameters：
Compression molding involves placing preheated plastic material into a heated mold cavity, then applying pressure (typically 5–50 MPa) and temperature (usually 120–200°C) to shape and cure the part. Key parameters include mold temperature, compression pressure, dwell time, and material viscosity, all of which affect the part’s dimensional accuracy and mechanical properties.
Application Scenarios:
This process is commonly used for producing large, complex, or high-strength plastic components such as automotive bumpers, electrical housings, and appliance panels. It is especially suitable for thermosetting plastics and composite materials that require precise molding and superior structural integrity.
These metal-plastic processes have different characteristics and application fields. Selecting the appropriate process can not only meet the design requirements, but also effectively control the cost and improve the performance and quality of the products. In the actual production, according to the demand and industry standards to select the appropriate process is crucial.
Common materials for custom plastic parts
Use this quick-reference table to compare popular engineering plastics by properties, typical applications, and notes for manufacturing. (Injection molding / CNC machining / surface finishing considerations.)
| Material | Common Grades | Key Properties | Typical Applications | Selection Notes |
|---|---|---|---|---|
| ABS | General / Flame-retardant | Tough, easy to mold, good surface finish | Housings, brackets, consumer & industrial covers | Accepts painting, plating, and textured finishes; moderate heat resistance |
| PC (Polycarbonate) | Optical / UV-stabilized | High impact, transparent options, good heat | Guards, lenses, transparent covers | Watch stress cracking; consider radius & proper gating |
| PC/ABS | Impact / FR blends | Balanced toughness + processability | Electrical enclosures, automotive interiors | Great all-rounder for tight cosmetic requirements |
| PA6 / PA66 (Nylon) | GF15–GF30 / heat-stabilized | Strong, wear-resistant, good fatigue | Gears, levers, clips, structural parts | Moisture absorption affects dimensions; define conditioning |
| PA12 | Low-moisture / flexible | Better dimensional stability vs PA6/66 | Fluid fittings, housings, functional prototypes | Often chosen when tight tolerance matters in nylon family |
| POM (Acetal) | Copolymer / Homopolymer | Low friction, excellent wear, stable | Precision gears, bushings, sliding components | Great for tight tolerance; avoid strong acids/oxidizers |
| PP | Copolymer / filled | Lightweight, chemical resistant, fatigue hinge | Containers, covers, chemical handling parts | Lower stiffness; add ribs; check shrink & warpage |
| HDPE | High-density | Excellent chemical resistance, tough | Linings, tanks, wear strips | Soft for precision features; consider inserts for threads |
| PMMA (Acrylic) | Optical | High clarity, good UV resistance | Light covers, display parts, windows | Brittle vs PC; avoid sharp corners; polish-friendly |
| TPU | Shore 70A–95A | Elastic, abrasion resistant | Seals, gaskets, protective covers | Define hardness & compression set requirements |
| PBT | GF / FR | Dimensional stability, electrical performance | Connectors, sensor housings, electrical parts | Often used for electrical; check creepage/CTI needs |
| PPS | GF40 / mineral filled | High heat, chemical resistance, rigid | Automotive under-hood, pump parts | Premium option; stable at temperature, but more brittle |
| PEEK | Virgin / GF / CF | High temperature, high strength, chemical resistant | Aerospace, medical (spec-dependent), high-load parts | High cost; define annealing & machining allowances if CNC |
| PTFE (Teflon) | Virgin / filled | Ultra-low friction, chemical inert | Seals, liners, sliding bearings | Soft material; consider backing/support design |
Tip: For faster quoting, provide material, color, finishing, tolerance, and annual volume (prototype vs mass production).
Notes: Properties vary by grade, filler, and processing method. For critical applications, confirm datasheets, service temperature, chemical exposure, and compliance requirements (e.g., ROHS/REACH/UL/food-contact as applicable).
The Common Pitfalls When Purchasing
Please note that the final cost depends on the customized service you require, the specifications of the raw materials used, the relevant national laws, and the distance of transportation. Take the example of booking a tall container of products:
- Improper material selection: improper material selection may lead to plastic parts can not reach the strength, corrosion resistance and other performance requirements, affecting the service life.
- Poor design: premature design can lead to difficulties in the production of plastic parts, increased costs and delays in delivery.
- Unreliable suppliers: some unprofessional suppliers may not be strict in quality control, resulting in nonconforming products or untimely delivery.
Our Work: A Glimpse into Our Capabilities
- Project Name:Automotive Sensor Housing
- Material: ABS+PC (enhanced heat resistance and impact strength)
- Process: High-Precision Injection Molding
- Key Tolerance: ±0.05mm
- Industry: Automotive Electronics
- Challenge & Solution: The customer needed a lightweight housing that could operate stably in high-temperature environments. Through material selection and mold optimization, we achieved the optimal balance between product performance and cost.
- Project Name: Heavy-Duty Sensor Connector Housing
- Material: PA66-GF30 (30% glass fiber reinforced nylon, high temperature resistance, oil resistance, and impact resistance)
- Process: High-Precision Injection Molding, with automated insert molding and online dimensional monitoring
- Key Tolerance: Key locking clips and sealing groove tolerances controlled within ±0.05 mm
- Industry: Construction & Off-Highway Machinery
- Challenge & Solution: By selecting PA66-GF30 material, adding reinforcing ribs and guide surfaces to the structure, and optimizing the clip position and wall thickness design, we controlled mold and unit costs while ensuring strength and dimensional stability.
The Process Flow & Duration Estimation
Please note that the final cost depends on the customized service you require, the specifications of the raw materials used, the relevant national laws, and the distance of transportation. Take the example of booking a tall container of products:
Step 1: Design and development
- Customer requirement analysis: According to customer requirement, designer and engineering team analyze and confirm the specification, function and material requirement of parts.
- 3D modeling and design optimization: Use CAD (computer-aided design software) to build 3D models of parts to ensure that the design meets engineering requirements and make necessary design optimizations.
- Sample confirmation and modification: After the design is completed, the prototype sample is usually made for verification to ensure that the design meets the actual use requirements. Make necessary adjustments based on feedback.
Step 2: Design and manufacture of die and mould
- Mold design: According to the complexity of the parts, design the appropriate mold. For metal-plastic composite parts, the combination of metal part and plastic part should be taken into account in mold design.
- Mold Manufacturing: Mold manufacturing is a key step in the production process, usually using high precision machining technology (such as CNC machining, Electrical discharge machining) to manufacture the mold.
- Die testing and optimization: After the completion of the manufacturing die testing, testing the working effect of the die, and according to the need to optimize the adjustment.
Step 3: Raw material preparation
- Material selection: According to the functional requirements of parts, select the appropriate metal materials, such as stainless steel, aluminum alloy or other alloy metal.
- Plastic material selection: Choose suitable plastic materials, such as ABS, polycarbonate (PC) , nylon, etc. , taking into account the heat resistance, corrosion resistance, strength and other needs.
- Material preparation and inspection: Purchase and inspect the quality of materials to ensure that they meet production standards and design requirements.
Step 4: Implementation of production process
- Metalworking: Metal parts are usually shaped by turning, milling, stamping or casting to ensure dimensional accuracy and surface quality.
- Plastic Processing: Plastic parts through injection molding, extrusion molding, hot pressing and other processes. The combination of metal and plastic can be achieved by compression molding, metal injection molding and other processes.
- Synthesis and assembly: Metal and plastic parts are connected, fixed or embedded in a specific process to form a complete metal-plastic composite part.
Step 5: Surface treatment
- Metal surface treatment: According to the requirements of galvanized, spraying, painting, electroplating and other surface treatment, enhance metal corrosion resistance, oxidation resistance and aesthetics.
- Plastic Finish: Plastic parts may need to be painted, printed, or UV coated to improve appearance or durability.
Step 6: Quality Control and inspection
- Dimensional inspection: use high-precision measuring tools (such as calipers, coordinate measuring machines, etc.) to inspect the dimensions and tolerances of the parts to ensure consistency with the design.
- Performance test: carry out strength, corrosion resistance, high temperature resistance and other performance tests to ensure that its performance in the actual working environment meets the requirements.
- Conformity inspection: perform final conformity inspection after all tests are completed to ensure that parts meet production standards and customer requirements.
Step 7: Packaging and delivery
- Parts packaging: According to the characteristics of the product, the use of appropriate packaging materials, such as shockproof packaging, plastic bags, cartons, etc. , to ensure that the parts are not damaged during transportation.
- Delivery and logistics: Arrange the appropriate transportation mode, ensure the delivery of products to customers on time, and provide the necessary transportation tracking services.
Step 8: Delivery of finished product
Upon completion of all inspection and post-processing, the castings will become the final product, ready to be delivered to the customer or used for assembly.
Ready to take your project to the next level?
Contact us today to discuss your manufacturing needs or request a free quote tailored to your specifications.
Custom Plastic Parts Surface Finishing
that Looks Premium and Works Better
From cosmetic textures to functional coatings, we help you choose a finish that matches your part’s purpose: appearance, wear resistance, grip, sealing, printing, bonding, or easy cleaning. Share your drawing + target look, and we’ll recommend the right finishing route.
Finishes You Can Specify (and We Can Repeat)
Pick the look. Tell us the function. We’ll engineer the finish so every batch matches.
Cosmetic Appearance
Make the part look “brand new” and high-end—without over-costing.
- Matte / semi-gloss / high gloss control
- Texture patterns (anti-fingerprint, leather-like, fine sand)
- Color matching with stable batch consistency
Functional Performance
For wear, friction, sealing, chemicals, UV, or easy-clean requirements.
- Deburring + edge smoothing (touch-safe handling)
- Coatings for abrasion / UV / chemical splash resistance
- Surface prep for sealing and long-life mating
Marking, Printing & Bonding
Make your logo/labels stick, and your assemblies hold under stress.
- Surface activation / primer for stronger adhesion
- Logo-ready textures (print-friendly, less smearing)
- Improved bonding for insert-molding or assembly glue
Our Finishing Workflow (Simple, Repeatable, Documented)
We control the details that buyers care about: appearance consistency, measurable function, and stable delivery.
| Finish option | What it’s for | Common materials | Notes |
|---|---|---|---|
| Matte / Gloss Control | Premium look, anti-fingerprint feel | ABS / PC / PA / POM | Appearance criteria can be agreed with samples |
| Texture / Grip Surface | Better handling, reduced glare | ABS / PA / PP | Texture depth can be customized |
| Protective Coating | Wear, UV, splash resistance | PC / PA / POM | Choose coating based on environment & lifespan |
| Print/Label Ready Prep | Stable logo marking, less peeling | ABS / PC / PP | Surface activation / primer available |
| Deburr + Edge Smoothing | Touch-safe edges, better fit | All plastics | Recommended for handheld/medical housings |
PDF/STEP/DWG.
Send your part drawing + target look (photo/reference). We’ll reply with a suggested finishing route, key risks (scratches, color shift, adhesion), and a practical inspection checklist.
Surface Finishing FAQs
Quick answers buyers and engineers ask before approving a plastic part finish.
Industry trends in custom plastic parts
The Future of Plastic Parts Manufacturing
The plastics manufacturing industry is rapidly embracing sustainable materials, such as bioplastics and recycled polymers, to reduce environmental impact and meet global eco-standards. At the same time, smart manufacturing and automation—powered by advanced robotics, IoT, and data analytics—are driving greater efficiency, precision, and flexibility across production lines.
By integrating these cutting-edge trends, our company is committed to delivering high-quality, environmentally responsible plastic components while leading the way in intelligent, automated manufacturing solutions for the future.
FAQS
What is your minimum order quantity (MOQ) for custom plastic parts?
Our MOQ varies depending on part complexity and material, but most custom plastic components start from 200–500 pcs. For development projects, we also support small trial batches to help you validate design and performance.
What file formats do you accept for quotes and manufacturing?
We accept all major 2D and 3D engineering formats, including:
STEP (.step / .stp), IGES (.igs), Parasolid (.x_t / .x_b), CAD (.dwg / .dxf), and PDF for drawings.
Providing a 3D model ensures faster and more accurate quoting.
What is the typical lead time for a new injection mold and the first batch of parts?
Lead time depends on mold complexity, but typical timelines are:
Simple molds: 15–20 days
Medium-complexity molds: 20–30 days
High-precision or multi-cavity molds: 30–45 days
After mold approval, the first batch of parts is usually delivered within 5–10 days.
How do you ensure the quality and consistency of your plastic parts?
Quality is controlled through our full ISO 9001 system, including:
IQC – Incoming Material Inspection
IPQC – In-Process Quality Control during molding and machining
FQC / OQC – Final and Outgoing Inspection
Dimensional reports, hardness tests, fitment checks, and optional PPAP elements for OEM programs
Every batch is fully traceable to tooling, material lot, and process parameters.
Can you help with material selection for my application?
Absolutely. Our engineering team can recommend materials based on temperature requirements, impact strength, UV exposure, chemical resistance, insulation properties, and more.
Common options include: ABS, PC, PA66, PA66-GF30, POM, TPU, PP, PE, and high-performance engineering plastics if needed.
Our Certificate
Third-party verification supports supplier approval. Below are our ISO 9001 certificate, SGS test report, and CNIPA utility model patents. If you need a PDF copy for internal review, tell us which document you require.
A Brief Self-Nomination, Why Choose Prime?
Choose Us, you will get reasonable prices, high quality, on time delivery of plastic parts solutions.
Experience: we have more than 30 years of plastic parts production experience, can provide high-quality custom metal plastic parts for the industry.
Professional team: Our engineering team is familiar with plastic parts technology and can provide accurate design and production services.
Quality assurance: We are ISO 9001 certified to ensure that each plastic part meets the highest quality standards.
Rapid Response: We are committed to providing fast sample production and production cycle, to ensure that your needs can be met in a timely manner.
Global Services: No matter where you are, we can provide you with quality services to ensure the smooth progress of your business.
Your Trusted Resource for Metal Parts Sourcing
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Get in touch
Custom Hardware Parts Made Easy
At Prime, we simplify the process of sourcing high-quality, customized hardware parts for your business. Follow these three simple steps to get started:
Tell Us Your Requirements
Share detailed information about your needs, including drawings, reference images, and any specific ideas or specifications you have in mind.
Receive Tailored Solutions & Quote
Based on your requirements and design, we’ll provide a custom solution and send you a detailed quote within 24 hours.
Approve for Production
Once you approve the design and quote, we’ll begin mass production and take care of the shipping, ensuring timely delivery.
Get a Free Quote
Reach out to us for a free quote and expert advice on your custom hardware needs. At Prime, we’ll provide the right solution for your project, ensuring quality and precision every step of the way.