Key Considerations for Prototype Machining: Ensure Quality and Meet Design Verification Needs

Prototyping is a crucial step in the product development process. A well-made prototype can effectively verify the feasibility of a product design, detect potential problems in advance, and lay a solid foundation for the subsequent mass production. No entanto, prototype machining is a complex process that requires attention to multiple details. This article will elaborate on the key considerations for prototype machining from various angles to help you successfully complete the prototype production.

1. Seleção de material: Lay the Foundation for Prototype Quality

The choice of materials directly affects the performance, aparência, and cost of the prototype. When selecting materials, you need to fully consider the characteristics and application scenarios of the final product.

It is important to note that different materials have different processing difficulties and costs. You should balance performance, custo, and processing difficulty to select the most suitable material.

2. Design Review: Avoid Errors Before Machining

Before starting the prototype machining, a detailed design review is essential. This step can help detect and correct errors in the design document in a timely manner, avoiding unnecessary losses caused by design problems during the machining process.

Key Points of Design Review

• Dimensions: Check whether all dimensional data in the design document are accurate, incluindo comprimento, largura, altura, and various hole positions. Ensure that the dimensions are consistent with the design requirements and there is no ambiguity.
• Accessory Interfaces: Verify the compatibility of accessory interfaces, such as the interface between the shell and internal components, and the connection between different parts. Ensure that the interfaces can be accurately matched and assembled smoothly.
• Moving Parts: For prototypes with moving parts, such as hinges and sliding mechanisms, check whether the movement path, range, and force of the moving parts are reasonable. Ensure that the moving parts can operate flexibly without jamming.
• Marking: Confirm that all necessary marks in the design document are complete and clear, such as dimension marks, material marks, and assembly marks. These marks are crucial for the machining and assembly of the prototype.

3. Precision Requirements: Clarify Standards for Machining

Clarifying the precision requirements of the prototype is the basis for selecting the appropriate machining method and ensuring the prototype meets the design verification needs. Precision requirements mainly include dimensional tolerance and geometric tolerance.

Common Precision Indicators and Their Requirements

• Dimensional Tolerance: It refers to the allowable variation range of the actual size of the prototype relative to the design size. Por exemplo, if the design size of a part is 50mm and the dimensional tolerance is ±0.1mm, the actual size of the part should be between 49.9mm and 50.1mm. The dimensional tolerance should be determined according to the functional requirements of the prototype. For precision parts such as gears and bearings, the dimensional tolerance is usually required to be within ±0.01mm; for general structural parts, the dimensional tolerance can be relaxed to ±0.1mm or ±0.2mm.
• Geometric Tolerance: It includes form tolerance and position tolerance. Form tolerance refers to the allowable variation of the shape of the prototype, such as flatness, straightness, and roundness. Position tolerance refers to the allowable variation of the position of the prototype relative to the reference, such as parallelism, perpendicularity, and coaxiality. Por exemplo, the flatness of a precision platform prototype may be required to be within 0.005mm/m, and the perpendicularity of two mutually perpendicular surfaces may be required to be within 0.01mm.

4. Surface Treatment: Improve the Appearance and Performance of the Prototype

Surface treatment can not only improve the appearance of the prototype but also enhance its performance, such as corrosion resistance, resistência ao desgaste, and electrical conductivity. The choice of surface treatment method should be based on the material of the prototype, the application scenario, and the design requirements.

Common Surface Treatment Methods and Their Applications

• Grinding and Polishing: This method can remove burrs and scratches on the surface of the prototype, making the surface smooth and flat. It is suitable for most materials, such as metal, plástico, and wood. After grinding and polishing, the surface roughness of the prototype can be reduced to Ra 0.8μm or lower.
• Pulverização: Spraying can form a uniform coating on the surface of the prototype, which can improve the appearance and corrosion resistance. Common spraying materials include paint, powder, and coating. Por exemplo, automotive prototype shells often use spraying to achieve the desired color and gloss.
• Eletroplatação: Electroplating can form a metal coating on the surface of the prototype, such as chrome, níquel, and copper. It can improve the wear resistance, Resistência à corrosão, and electrical conductivity of the prototype. It is widely used in metal prototypes, such as hardware accessories and electronic connectors.
• Anodizing: Anodizing is mainly used for aluminum and its alloys. It can form a dense oxide film on the surface of the prototype, which has good corrosion resistance and decorative properties. The color of the oxide film can be adjusted according to the needs, such as black, prata, and red.

5. Manufacturing Process Selection: Choose the Most Suitable Method

There are many manufacturing processes for prototypes, each with its own advantages and limitations. The selection of the manufacturing process should be based on the material of the prototype, the complexity of the structure, the precision requirements, the production cycle, and the cost.

Comparison of Common Manufacturing Processes

6. Assembly and Functional Testing: Ensure the Prototype Works Normally

If the prototype consists of multiple parts, assembly and functional testing are crucial steps. Assembly quality directly affects the performance and stability of the prototype, and functional testing can verify whether the prototype meets the design requirements.

Assembly Considerations

• Assembly Convenience: When designing the prototype, consider the assembly sequence and method to ensure that the parts can be easily assembled. Avoid designing overly complex assembly structures that increase assembly difficulty and time.
• Fit Precision: Check the fit precision between the parts during assembly, such as the clearance and interference between the shaft and hole. Ensure that the fit precision meets the design requirements to avoid problems such as loose or tight assembly.
• Fastener Selection: Choose appropriate fasteners, such as screws, nuts, and bolts, according to the needs of the prototype. Ensure that the fasteners have sufficient strength and reliability to prevent the prototype from loosening or falling apart during use.

Functional Testing Content

• Performance Testing: Test the performance indicators of the prototype, como força, dureza, elasticity, and heat resistance. Por exemplo, test the bearing capacity of a mechanical prototype and the high-temperature resistance of an electronic product prototype.
• Operation Testing: For prototypes with operating functions, such as buttons, switches, and knobs, test their operation sensitivity and reliability. Ensure that the operating parts can work normally and respond quickly.
• Compatibility Testing: If the prototype needs to be used with other equipment or components, conduct compatibility testing to ensure that the prototype can work normally with them.

7. Quality Control: Ensure the Prototype Meets the Standards

Quality control should run through the entire prototype machining process, including pre-machining, in-machining, and post-machining. Only by implementing strict quality control can the quality of the prototype be ensured.

Quality Control Measures at Different Stages

• Pre-Machining Quality Control: Check the quality of raw materials, such as the material composition, mechanical properties, and surface quality. Verify the accuracy of the design document and the machining process plan.
• In-Machining Quality Control: Conduct intermediate inspections during the machining process, such as checking the dimensions, forma, and surface quality of the parts. Monitor the machining parameters, such as cutting speed, feed rate, and depth of cut, to ensure that they are within the specified range.
• Post-Machining Quality Control: Perform a final inspection of the prototype, including a comprehensive check of dimensions, geometric tolerance, tratamento de superfície, and assembly quality. Conduct functional testing to ensure that the prototype meets the design requirements. For prototypes with high precision requirements, use professional testing equipment, such as coordinate measuring machines and surface roughness meters, for testing.

8. Communication and Feedback: Promote the Smooth Progress of the Project

Close communication between the prototype machining party, designers, and engineers is essential. Timely feedback on problems and challenges encountered during the machining process can help adjust the design and process in a timely manner, ensuring the smooth progress of the project.

Communication Points and Feedback Methods

• Communication Points: During the prototype machining process, the machining party should communicate with designers and engineers on the following points: material selection, design document understanding, machining process selection, surface treatment methods, and assembly problems. Designers and engineers should provide timely feedback on the machining party’s questions and suggestions.
• Feedback Methods: Establish an effective feedback mechanism, such as regular meetings, email communication, and online messaging. The machining party should promptly feedback the progress of the prototype machining, problems encountered, and solutions to designers and engineers. Designers and engineers should timely review and approve the feedback content and put forward adjustment opinions if necessary.

9. Confidentiality Agreement: Protect Intellectual Property

If the prototype project involves commercial secrets or intellectual property, it is necessary to sign a confidentiality agreement with the prototype manufacturing company. The confidentiality agreement should clearly stipulate the scope of confidentiality, the confidentiality period, and the liability for breach of contract to ensure that the intellectual property of the project is protected.

When signing a confidentiality agreement, you should pay attention to the following points:

• Clearly define the scope of confidential information, including design documents, technical data, process parameters, and prototype samples.
• Determine a reasonable confidentiality period, which should be at least until the product is officially launched or the intellectual property is no longer confidential.
• Stipulate strict liability for breach of contract, such as compensation for economic losses and legal liability, to deter the prototype manufacturing company from disclosing confidential information.

10. Delivery Time: Ensure the Project Progress is Not Affected

The delivery time of the prototype is an important factor affecting the project progress. When entrusting the prototype manufacturing company, you should confirm the delivery time and clearly stipulate it in the contract. At the same time, you should track the progress of the prototype machining in a timely manner to ensure that the prototype can be delivered on time.

To ensure the on-time delivery of the prototype, you can take the following measures:

• Choose a prototype manufacturing company with rich experience and a good reputation, which has the ability to complete the prototype machining within the specified time.
• Establish a progress tracking mechanism, require the prototype manufacturing company to report the machining progress regularly, and promptly find and solve problems that may affect the delivery time.
• In the contract, stipulate the penalty clauses for delayed delivery, such as deducting a certain percentage of the payment for each day of delay, to urge the prototype manufacturing company to deliver on time.

Yigu Technology’s View on Prototype Machining

Na tecnologia Yigu, we recognize that prototype machining is a vital link in product development. We always adhere to strict quality standards in prototype production, carefully selecting materials based on customer needs, conducting in-depth design reviews, and choosing the most suitable manufacturing processes. Our professional team pays close attention to every detail from machining to assembly and functional testing, ensuring each prototype meets high precision and performance requirements. We also value communication with customers, timely feedback on progress and issues, and strictly abide by confidentiality agreements to protect customer intellectual property. We believe that high-quality prototypes can help customers accelerate product development and gain a competitive edge in the market.

Perguntas frequentes

Q1: What factors should be considered when choosing a prototype manufacturing process?

A1: When choosing a prototype manufacturing process, you need to consider the material of the prototype, the complexity of the structure, the precision requirements, the production cycle, and the cost. Por exemplo, if you need a high-precision metal prototype with a complex structure, CNC machining may be a suitable choice; if you need a small-batch complex structural prototype quickly, 3D printing is more appropriate.

Q2: How to ensure the surface treatment quality of the prototype?

A2: To ensure the surface treatment quality of the prototype, primeiro, select a suitable surface treatment method according to the material and design requirements. Então, strictly control the surface treatment process parameters, such as temperature, tempo, and chemical concentration. Before surface treatment, thoroughly clean the surface of the prototype to remove oil, rust, and other impurities. After surface treatment, conduct a detailed inspection of the surface quality, such as checking for defects such as bubbles, rachaduras, and uneven coating.

Q3: What should I do if the prototype fails the functional test?

A3: If the prototype fails the functional test, primeiro, analyze the cause of the failure. It may be due to design errors, assembly problems, material defects, or machining errors. Então, according to the cause of the failure, take corresponding measures. If it is a design error, modify the design document; if it is an assembly problem, re-assemble the prototype; if it is a material defect, replace the material; if it is a machining error, re-machine the relevant parts. After taking the measures, re-conduct the functional test until the prototype passes the test.