Professional 3D Printing Services in China

Bruce Lee Style Molds/Injection Molding

Bruce Lee is a globally celebrated cultural icon and martial arts master who profoundly promoted traditional Chinese martial arts across the world. He made history by introducing “Kung Fu” to Western countries and earned numerous prestigious honors, including induction into the Black Belt Hall of Fame, Time Magazine’s list of the 100 Most Influential People of the 20th Century, and the Hong Kong Film Awards Lifetime Achievement Award. As an eternal symbol of diligence, precision and perseverance, Bruce Lee has always been the spiritual idol of Mr. Ding, founder of Gold Chain Trading Company.

The company strictly inherits and practices Bruce Lee’s spirit in daily operation and quality management.

Rapid Response: Decisive and efficient like Bruce Lee, we respond quickly to customer needs without procrastination.
High Precision: We pursue rigorous craftsmanship, ensuring all product testing data fully meets international standards.
Steady Attitude: We maintain a professional, confident and down-to-earth mindset, constantly pursuing excellence in mold design and injection molding manufacturing for global clients.

What is the principle behind 3D printing?

3D printing (additive manufacturing) is a technology that creates three-dimensional objects by adding materials layer by layer.

Its basic principle is as follows: First, a three-dimensional digital model is designed using computer software. Then, the model is horizontally “sliced” into a series of extremely thin two-dimensional planar layers. The printer reads this slice data and precisely deposits material (such as plastic, metal, resin, etc.) layer by layer on the printing platform. After each layer of material is deposited or solidified, the platform slightly lowers or the print head rises, and then the next layer is deposited, with the new layer firmly bonded to the previous one. This process is repeated, layer by layer, until a complete three-dimensional object is built from bottom to top.

The entire process is similar to laying bricks layer by layer when building a house, but it is fully automated by a computer, enabling the creation of complex shapes that are difficult to manufacture using traditional methods.

Which fields can 3D printing be applied to?

3D printing technology is extending from industrial manufacturing to everyday life. Its core value lies in its ability to quickly and cost-effectively manufacture complex structures and personalize them. Currently, its main applications are concentrated in the following areas:

Medical and Healthcare (Highly Personalized)

This is one of the most transformative areas of 3D printing. The technology can be directly used to create preoperative planning models, surgical guides, and customized implants (such as bones and dental crowns) and rehabilitation aids that perfectly match the patient’s anatomy, enabling precision medicine. Cutting-edge bio-3D printing is even researching the printing of living tissue or organ scaffolds.

Aerospace (Pursuit of High Performance)
This field has mature applications, primarily utilizing 3D printing to manufacture complex, lightweight parts that are difficult to process using traditional methods. For example, by molding parts with internal cavities or lattice structures in a single piece, the weight of aircraft or satellites can be significantly reduced while ensuring strength and meeting extreme performance requirements.

Automotive and Consumer Electronics (Driving Rapid Innovation)

In the automotive industry, 3D printing is widely used to rapidly produce functional prototypes, tooling fixtures, and even directly manufacture lightweight parts, significantly shortening the R&D cycle. In the consumer electronics sector, with companies like Apple entering the market, 3D printing is expected to be used to manufacture more complex and robust structural components for devices.

Cultural and Creative Industries & Education (Popularization and Creativity)

This is the main market for consumer-grade 3D printing. It allows artists and designers to freely transform complex ideas into physical objects (such as sculptures and jewelry), and has become a common tool in schools and maker spaces for teaching demonstrations, model making, and inspiring innovative practices.

Architecture & Future Fields

In the construction field, concrete 3D printing technology can be used to quickly construct houses or special landscape components. In the future, with technological advancements, 3D printing also has broad potential in areas such as humanoid robot manufacturing and personalized medicine.

Is secondary processing required after 3D printing?

Yes, the vast majority of 3D printed parts require secondary processing after completion. This post-processing stage is crucial to the performance, precision, and appearance of the final product; it can be considered an essential step “from model to finished product.”

The necessity, complexity, and specific steps of post-processing depend primarily on the printing technology used and the intended use of the final product.

1. The most common support removal and surface treatment

For commonly used fused deposition modeling (FDM) (plastic materials) and photopolymerization (PRC) technologies, post-processing is almost mandatory:

• Support removal: Supports created for printing suspended structures must be removed manually or with tools.

• Basic cleaning: Resin prints must be thoroughly cleaned with alcohol to remove uncured, sticky resin from the surface.

• Surface polishing: Layer textures from FDM printing and traces left after support removal typically require polishing to achieve a smooth surface.

• Post-curing: After cleaning, resin prints require secondary curing under UV light to achieve complete curing and final strength.

2. Enhancement Processing for Functionality and Appearance

To meet higher requirements, the following processing methods are often used:

• Precision Machining: For parts requiring assembly, critical dimensions may require drilling, tapping, or CNC milling to meet drawing tolerances.

• Performance Enhancement: Some plastic parts (such as nylon) undergo infiltration or coating to improve airtightness or strength; almost all metal printed parts require heat treatment (stress-relief annealing, hot isostatic pressing) to eliminate internal stress and improve mechanical properties.

• Aesthetic Finishing: Painting, electroplating, and dyeing significantly improve the appearance to meet the requirements of display or consumer-grade products.

3. The Special Characteristics of Metal Printing: Processing is Crucial

Metal 3D printing, exemplified by Selective Laser Melting (SLM), requires particularly complex and necessary post-processing:

• Separation from the Substrate: Printed parts need to be separated from the building substrate using wire cutting, milling, or other methods.

• Stress Relief: Heat treatment is necessary to eliminate high residual stresses from the printing process and prevent deformation or cracking of the parts. • Surface Finishing: Sintered residual powder from internal flow channels or complex surfaces requires ultrasonic cleaning or sandblasting for removal.

• Precision Assurance: Due to potential microscopic undulations on the printed surface, achieving mirror finish or tight fit tolerances typically necessitates CNC machining. Therefore, “3D printing + CNC finishing” has become the golden combination for manufacturing high-performance metal parts.

What are the raw materials used in 3D printing?

3D printing uses a variety of raw materials, and their selection is strongly tied to specific printing technologies. The main material types, characteristics, and corresponding technologies are as follows:

Three Main Material Types

1. Plastic Filament (Applicable to FDM/FFF technologies)
This is the most common material for consumer-grade printing, used in filament rolls.

* PLA (Polylactic Acid): Environmentally friendly and biodegradable, with low printing temperatures and no odor, suitable for beginners and educational uses, often used for models and figurines. However, its heat resistance is poor, softening easily above 60°C.

* ABS: Good strength and impact resistance, can withstand temperatures up to approximately 100°C, often used for tool fixtures and part prototypes. A heated base plate and ventilation are required during printing.

* PETG: Excellent overall performance, combining the ease of printing PLA with the toughness of ABS, resistant to chemical corrosion and waterproof, suitable for outdoor products and functional components.

* TPU: A flexible material with rubber-like elasticity and abrasion resistance, used for printing phone cases, insoles, and sealing rings. 2. Photosensitive Resins (Specifically for SLA/DLP/LCD Technologies)
These are liquid materials that are cured layer by layer by light of a specific wavelength, known for their high precision and smooth surface finish.

• Standard/Rigid Resins: General-purpose materials with strong detail rendering capabilities, widely used in jewelry casting, dental models, and precision prototyping.

• Flexible Resins: Elastic after curing, simulating the texture of rubber or silicone, used for flexible joints, footwear prototypes, etc.

• High-Temperature Resins: Can withstand temperatures above 150°C, used for functional prototype testing requiring heat resistance, such as lighting components.

• Casting Resins: Designed specifically for investment casting, producing very little ash after combustion, used for creating wax models for precision casting.

3. Metal Powders (Specifically for SLM/SLS Technologies, etc.)
These are industrial-grade materials, formed by laser layer-by-layer melting or sintering of powder, used to manufacture high-strength, highly complex end-use metal parts.

• Stainless steel (e.g., 316L): Excellent corrosion resistance, suitable for medical devices, food industry parts, and aerospace components.

• Titanium alloys (e.g., TC4): High strength, lightweight, and excellent biocompatibility, ideal for lightweight aerospace components and medical implants (e.g., artificial joints).

• Aluminum alloys (e.g., AlSi10Mg): Lightweight and with good thermal conductivity, commonly used in lightweight automotive parts and radiators.

• Other alloys: Includes cobalt-chromium alloys (used in dentistry and orthopedics), copper alloys (used for components requiring high thermal and electrical conductivity), etc.

Other special and cutting-edge materials

• Ceramic materials: Formed using techniques such as binder spraying or photopolymerization, requiring high-temperature sintering, the finished product possesses high-temperature resistance and corrosion resistance, suitable for artistic creations and special parts.

• Composite and special materials: For example, adding carbon fiber or glass fiber to plastics can significantly improve the strength and stiffness of the material, used in drone frames, high-performance fixtures, etc. • Cutting-edge materials: Research areas also include biomaterials (such as cell culture media) and smart materials (such as materials with shape memory or responsiveness required for 4D printing).

How is the price of 3D printing services calculated?

The price of 3D printing services is usually not a fixed price. It is composed of core components such as material costs, labor and machine depreciation, and post-processing fees, and is influenced by factors such as printing technology, materials, model complexity, and quantity.

To help you understand quickly, here is a summary of the main factors affecting the price and common billing methods:

Core Factors Affecting Price

1. Technology and Materials: This is the foundation for price. Printing with ordinary PLA plastic is the most economical; photosensitive resin (used for SLA/LCD technology) offers high precision at a moderate price; while industrial-grade nylon and metal powder printing are the most expensive.

2. The Model Itself

· Volume and Weight: The more material consumed, the higher the price.

· Printing Time: The taller or more complex the model, the longer the printing time and the higher the machine cost.

· Precision and Complexity: The more detailed the required features and the more suspended structures (requiring more support), the higher the printing and post-processing costs.

3. Post-Processing: Additional services such as sanding, painting, and assembly will increase costs. 4. Print Quantity: Batch printing usually spreads out the setup and debugging costs, resulting in a more affordable average price per piece compared to printing only one item.

Common Billing Methods

* “Materials Cost + Setup/Service Fee”: This is the most common model. Total price = Material volume consumed by the model × Material unit price + a fixed setup/service fee.

* “Modeling Fee + Printing Fee”: For cases requiring the creation of a 3D model from scratch (such as custom portraits), a separate modeling and design fee will be charged, and the printing cost will be calculated based on the model.

* Time-Based Billing: Some platforms or shared services charge based on machine printing hours, usually including material wastage.

* Package Pricing for Complex Projects: For demanding and complex projects, service providers typically offer a comprehensive package price after evaluation.

What are the differences in strength between products manufactured using the same raw materials through 3D printing, injection molding, and CNC machining?

Products manufactured using the same raw materials through 3D printing, injection molding, and CNC machining exhibit fundamental differences in strength. This primarily stems from the fundamental impact of manufacturing processes on material continuity, internal structural consistency, and mechanical anisotropy.

To help you quickly understand these core differences, please refer to the following comparison:

1. Interlayer Bonding in 3D Printing

Core Weakness: 3D printing does not “weld” materials together. Layers are bonded together through the surface of a hot-melt plastic. This results in interlayer bond strength being much lower than the intermolecular forces within the material. Therefore, when subjected to tensile forces or impacts perpendicular to the layer direction, the product is most prone to cracking between layers.

Internal Uncertainty:Even with 100% infill, micropores or incompletely fused gaps may still exist internally, becoming stress concentration points.

2. Injection Molding: Seamless Bond – Homogeneous Monolith

High Strength Foundation: Molten plastic is injected into a mold under high pressure (typically tens to hundreds of megapascals). The molecular chains intertwine and tightly arrange themselves, forming a continuous, dense, isotropic monolith upon cooling. Its strength is closest to the material’s theoretical value.

Major Weakness: If the product structure is complex, the molten plastic may flow in different directions within the mold, forming weld lines that significantly reduce the strength at these points.

3. CNC Machining: Preserving Raw Material Properties

Performance Limits: CNC machining, cutting from solid sheet or bar stock, can fully inherit the dense structure and excellent properties of the original raw material (assuming the blank is defect-free). Generally, it is the strongest and most reliable of the three methods.

Cost and Limitations: Machining generates a significant amount of waste and is limited by the cutting tools, thus preventing the creation of overly complex internal structures.

Summary and Selection Recommendations

For the highest strength and reliability: CNC machining should be the first choice, followed by injection molding. They can provide “solid” parts that are closest to the ideal material properties. The core advantage of 3D printing lies in its ability to freely create complex geometries, rapid prototyping, and small-batch customization, rather than ultimate mechanical performance. For load-bearing structural components, the anisotropic weakness must be compensated for by optimizing the printing direction (making the principal stress direction parallel to the printed layer) and design.

Therefore, for parts that need to withstand high loads, impacts, or have stringent long-term reliability requirements, unless specially designed and optimized (e.g., using continuous fiber-reinforced industrial-grade 3D printing), the “strength” of 3D-printed parts is generally lower than that of injection-molded parts, and even significantly lower than that of CNC-machined parts, even when using the same materials.

If you can specify the raw materials (e.g., ABS, nylon, or metal) and the specific stress conditions of the product, I can provide a more detailed analysis.

What formats are supported for 3D printing modeling data?

3D printing modeling data is mainly divided into two categories: general-purpose 3D model formats (for design and exchange) and printer-specific formats (for final slicing and control). Their core differences and selection suggestions are as follows:

Format Type | Common Formats | Main Features and Uses | Advantages | Disadvantages

OBJ | Supports multiple colors and texture maps in addition to geometry. | Richer information than STL. | Files are usually larger than STL, compatibility is slightly lower than STL.

3MF | Next-generation format, designed to replace STL. | Packages and encapsulates all information (geometry, color, material, configuration, etc.). | Comprehensive functionality, high file efficiency, the future trend. | Newer, some older software may not fully support it.

STEP / IGES | Contains precise CAD data (surfaces, curves), used for high-precision exchange in engineering fields. Extremely high precision, non-destructive modification possible. Large file size, requires conversion to STL or other mesh formats for printing.

G-code, a printer-specific format: The final instruction set executed by the printer, generated by slicing software based on the 3D model. Directly controls all printer actions. The model cannot be reverse-modified; specific to certain machines.