A prototipagem CNC é um processo preciso, e processo preciso. It accommodates a variety of materials providing a great deal of variations. Several CNC machines improve these characteristics making the process more flexible. No entanto, knowing how to apply those techniques to CNC prototyping is quite important. This way, it is possible to know the best process that can be used to produce the prototypes effectively. Prototyping allows manufacturers to quickly create and iterate designs. This guide will help demystify the process and explain how to go about it.
What is CNC Prototyping?
CNC prototyping uses CNC machines to come up with prototypes within the shortest time possible. Ideally, production runs are limited in number and are oriented toward the creation of visual and tangible prototypes of the final product. It’s considered the best process of achieving the actual production from computer-generated designs.
Manufacturers can point out design errors at an earlier stage in the process. Solving such problems during the prototyping stage is beneficial in achieving affordable production.
Importance of CNC Prototyping In Machining
Fresamento CNC is particularly used in prototyping. Primeiramente, this approach has an incredible level of accuracy and precision because of the automatic control of the workpiece and cutting tool position. These advanced systems examine designs in all aspects while the prototype produced appears very close to the actual final product.
Além disso, CNC technology is faster as compared to other processes such as injection molding. With CNC prototyping, the time to finalize tolerances and molds is short as opposed to injection molding which takes relatively a lot of time.
Prototyping begins with a 3D CAD model development of the product that is to be created. These are then translated to CAM files of the model. These CAM files hold the G Code through which the CNC machine operates while making prototypes.
How to Determine the Need for CNC Prototyping
Several considerations assist in determining whether a product part needs CNC prototyping.
- Size: The choice of material block size is important. It also helps to decide which type of CNC machine is appropriate for the specific project after knowing the prototype’s dimensions.
- Material: Cost considerations matter. Cheaper materials such as ABS in most cases cost less than aço inoxidável. Apesar disso, there are added advantages of using CNC prototyping since it is also possible to use cheap materials such as aluminum.
- Finishing Options: There are many finishing methods, each with distinct characteristics. Choices are to leave this part as machined, bead blast, anodize, or plate.
- Complexidade: The complexity of design severely influences CNC machining cycle time. Products that have complicated cross-sectional shapes or other specific features such as threaded through-holes, or engravings of logos, take longer to machine. These may require sophisticated machines with additional axes hence increasing the cost of the machines.
- Tolerância (Precisão): Tight tolerances increase the overall costs of prototyping. Obtaining higher accuracy increases the time spent on the project and the expenses needed for the work.
- Type of CNC Prototyping Machine: Geral, it can be said that CNC turning machines are cheaper than Fresadoras CNC. Apesar disso, turning machines are somewhat restrictive in their use, and these may not suit you depending on your project.
- Quantity: The number of prototypes ordered determines the price that is charged for them. Economies of scale are a concept under which the cost of producing many parts is lower than the cost of producing individual parts. A CNC prototyping firm takes into account the cost of setting up a machine in the total price of the project. To have several parts manufactured simultaneously reduces the time needed for setup and concentrates on machining.
Advantages of CNC Prototype Machining
CNC prototyping has the following benefits:
- Repeatability and Consistency: CNC machining delivers quality products with a high level of accuracy and repeatedly. The process will repeat itself for each of the finished products with those made using the same process.
- Alta Precisão: CNC machining results in small tolerances and high levels of precision. This accuracy is important for prototypes to have the same perfection as the actual designs.
- Time-Saving Process: CNC prototyping does not need molding. The fact that CAM and CAD files can be easily amended is a major boost to the process.
- Econômico: CNC machining reduces long-term costs. Eliminating defects on a small scale is more economical than having to deal with complications resulting from mass production.
- Material Diversity: CNC machining accepts different materials. Selections are available in strong metals and ligas, madeira, and plastics, where precise prototypes can be produced.
Materials Compatible For CNC Prototyping Machining
Common materials suitable for CNC prototyping include:
- Alumínio
- Aço
- Aço inoxidável
- abdômen
- Magnésio
- Titânio
- Zinco
- Latão
- Bronze
- Cobre
- Teflon
- Polycarbonates
- Polipropileno
- Polymethyl Methacrylate
- Poliestireno
- Polyoxymethylene
- PAGE
- PCGF
- Low-Density Polyethylene
- High-Density Polyethylene
Challenges of CNC Prototyping Processes
Despite its advantages, CNC prototyping has some limitations:
- Subtractive Process: CNC machining is a process that cuts material from a workpiece. This may lead to more material usage than additive processes and that is why it is preferred.
- Geometrical Restrictions: Several internal geometries cannot be produced. CNC machining works from the outside in, which limits certain shapes.
- Technical Expertise Required: CNC machines can only be operated with the right skills. CAD file creation knowledge is crucial to the job.
- Higher Costs Than 3D Printing: CNC prototype machining is normally characterized by higher material costs. But it’s more accurate and accommodates a wider range of materials. Most additive processes employ plastics such as PLA only, yet the process has many advantages. No entanto, PLA could be slightly expensive and might not offer the needed prototypes to all the clients.
CNC Prototype Machining vs. 3Impressão D
Professionals frequently compare CNC machining and 3D printing as prototyping methods. Both have unique advantages and applications, making it crucial to understand their differences.
| Fator | Usinagem CNC de Protótipos | 3Impressão D |
| Working Principle | Subtractive method removing material from a workpiece. | Additive method adding material layer by layer. |
| Supported Materials | Versatile options include metals, plásticos, e madeira. | Limited to thermoplastics. |
| Possible Geometry | Limited to external shapes, complex internal geometries are not feasible. | Capable of creating complex internal geometries. |
| Wastage | Higher material wastage, but recyclable waste can offset costs. | Minimal waste due to its additive nature. |
| Manufacturing Time | Geralmente mais rápido, capable of producing multiple parts quickly. | Mais devagar, taking hours for single parts. |
How to Create Quality CAD Models for CNC Prototype Machining
A CNC machined prototype is as good as the CAD file used in developing it. They contain significant visual characteristics and measurements required for the fabrication of parts. It is thus understood that high-quality prototypes require well-crafted CAD models. Here are some guidelines to consider when preparing these models:
Importance of a Checklist in Prototyping
The checklist is a very useful tool for developing and using in practice. Starts with an inventory of all design attributes and functions that you would like to see in your prototypes. Features are better added while designing the file for the first time than when the file has already been created.
Finalize Wall Thickness
It is also worthwhile to take care of suitable wall thickness while drawing the walls. Reducing the thickness of the walls of the custom CNC part compromises the mechanical stability of the part and therefore reduces its strength. It is typical to set a minimum of 0.8mm for the metal wall thickness and a minimum of 1.5mm for the plastic wall for maximum efficiency.
Optimize Design Elements
In the case of cavities and holes, there is another important aspect to be taken into consideration – the possibility of machining them using CNC. Por exemplo, in end milling operations, the depth of cut that is being made is generally limited to three times the tool diameter. Thus it’s necessary to define and restrict the diameter of these features to the appropriate measurements.
Select Suitable CAD Software
Due to the widespread of CAD in the manufacturing industry, many software options are available on the market for creating prototypes across various industries. Even though some software can be extremely helpful. There can be also programs that are too elaborate or limiting. Select the right CAD application that meets the specifications of your industry. Por exemplo, applications used in mechanical engineering especially in sheet metal forming may not be suitable for architectural drawings. Portanto, you must get the right CAD program that will fit the needs of your prototype.
Simplify Drawings
CAD facilitates the possibility of designing prototypes in different configurations. To reduce unnecessary machining operations, your drawings should be simple. For complicated parts, it’s possible to divide the drawing into two parts that can be joined together once it is being machined to enhance the drawing’s clarity.
Final Thoughts
CNC Prototypes are important tools in contemporary manufacturing. They save money and eliminate complications before the final design commencements. For the prototyping stage, the CNC-machined prototypes are more appropriate. These offer quick and precise models for several uses.
By applying the information in this article, you can design high-quality prototypes. One step involves utilizing tips for optimizing CAD design. This applies to, rapid manufacturing, simple CNC machines, and advanced CNC technology.
Are you looking for accurate prototypes at low cost? Tops Precision provides CNC-machined prototypes to your doorstep.
Perguntas frequentes
1º trimestre: What is CNC prototype machining?
CNC prototype machining is a form of subtractive manufacturing wherein the parts are manufactured by the removal of material from a single piece of stock using computer numerically controlled machines, which provide high accuracy and dimensional consistency.
2º trimestre: What type of materials can be applied to CNC prototypes?
CNC machining can work with many different types of material. Por exemplo; metais (aluminum and steel) and plastics (ABS and polycarbonate), making for not only aesthetics but also functionality in the prototypes.
3º trimestre: How does CNC machining enable it to have high precision?
CNC machining is characterized by precise movements of the tools about the workpiece, which is defined by a computer-aided design and can allow small tolerances.
4º trimestre: Why CNC Prototype machining is better than 3D printing in prototype manufacturing?
Compared to 3D printing, CNC machining is faster in production and provides better material selection. Além disso, it’s more accurate for functional and reliable prototype parts.
