Uma visão geral completa da usinagem CNC versus usinagem manual

A usinagem é uma operação central na fabricação, pois envolve fixar ou remover material de uma peça de trabalho, ou seja. metais para atingir a geometria necessária. CNC é uma das técnicas de usinagem mais utilizadas enquanto a outra é chamada de usinagem manual. Resumidamente, embora cada um tenha suas vantagens com base na complexidade da tarefa, precisão necessária, ou volume de produção, cada um tem sua proposta de valor única. Neste artigo, você aprenderá o que significa usinagem CNC e manual, como eles operam, e suas vantagens e desvantagens.

O que é usinagem CNC?

CNC is Computer Numerical Control which is a method in which a machine tool is operated with the help of a computer program to produce some parts with very high accuracy. The machine deploys computer program codes. Then they determine the movement of the tools, velocidade, and feed rates of the machine. CNC machining has a wide scope of applications in making complex and repetitive accuracy work. These industries may include automotive, aeroespacial, electronics manufacturing, etc..

O que é usinagem manual?

Manual machining involves an operator feeding and leading the cutting tools on the machining tools, ou seja. lathes, moinhos, and grinders to form the material. Unlike CNC, manual machining mainly depends on the worker’s skills and expertise regarding the tools. It is predominantly applied during single-operation jobs, repair works, or to produce items that do not have close tolerance requirements.

Como funciona a usinagem CNC?

The CNC machining process starts with defining a computer-aided design or a CAD model of the part to be machined. This model is then translated into CNC programming language, ou seja. G-code that directs the working of the machine. After the program is downloaded into the CNC machine by the computer, an operator configures the CNC machine, and then the computer takes over. The operation of cutting or milling takes place through the instructions left in the machine and few corrections are required on the parts.

Como funciona a usinagem manual?

In manual machining, mechanists operate and control the tools manually under his/her direct control. The motion of the tools is synchronized with the machine setting, ou seja. velocidade, profundidade de corte, and feed rate among others. The machinist manipulates the work with his hands by controlling the positions of the cutting tools. He helps form the material appropriately. Manual machining, por outro lado, has frequent interactions with the materials and physical operations, therefore it entails more manual operations and depends greatly on the skill of the worker.

A comparação entre usinagem CNC e usinagem manual

The following are the main differences between CNC and manual machining:

1. Automação

   CNC machining fully automates the machining process while in manual machining the process has to be run all the time.

2. Precisão

   CNC Machining is more accurate than manual machining. No entanto, in CNC machining, the operations are directed by a controlled program.

3. Complexidade

   Complex designs can be conveniently designed for the CNC machining process while manual machining is most suitable for simple ones.

4. Velocidade

   A CNC machine can fabricate a part much faster when compared to a manual machine particularly when it’s a large quantity.

5. Trabalho

   Manual machining needs a lot of concentration from an operator while CNC machines only need a small initial input and then they are set to go on their own.

6. Custo

   CNC machines are initially expensive to purchase while manually operated machining tools may prove to be expensive in terms of manpower during mass production.

The following table will summarize the major comparison between CNC machining and manual machining:

Factors	Usinagem CNC	Manual Machining
Automação	Fully automated.	Manual operation by a machinist.
Precisão & Tolerância	Alto: ±0.001″ (±0.025 mm).	Moderado: ±0.005″ (±0.127 mm).
Velocidade	Fast, ideal for high volumes.	Mais devagar, dependent on operator skill.
Complexidade	Ideal for complex geometries.	Best for simple designs.
Volume de produção	Efficient for large runs.	Suited for low-volume or one-off jobs.
Labor Requirement	Minimal after setup.	Alto, requires skilled labor throughout.
Cost per Part	Lower for large runs.	Higher due to labor costs.
Tempo de configuração	Alto: hours to days.	Baixo: minutes to hours.
Desperdício de Materiais	Baixo, minimal waste.	Higher due to human error.
Machine Cost	Alto: $50,000 para $500,000+.	Mais baixo: $5,000 para $50,000.
Skill Level	Requires CNC programming knowledge.	Hands-on machining expertise.
Repetition Accuracy	Consistent across parts.	Variability due to manual adjustments.
Ideal Use	High precision, complex, large runs.	Simple, custom, one-off jobs.

Quando escolher a usinagem CNC

CNC machining is one of the best methods of making complex parts and shapes and can be preferred in the following situations:

1. When making parts that are supposed to have high levels of accuracy and uniform quality.
2. Após testes e revisões completas do projeto original e provando que ele atendeu a todos os padrões de produção exigidos e está pronto para produção em massa.
3. Especificamente, ao projetar formas com muitos ângulos no ambiente digital seria possível criar em software manualmente.
4. Indústrias de alta precisão se estendem à indústria aeroespacial, automotivo, e setores eletrônicos onde precisão e consistência são fundamentais.
5. Quando a automação e subsequentemente menos mão de obra são desejadas para economizar tempo.

Quando escolher a usinagem manual

Aqui estão alguns pontos onde podemos ir com a usinagem manual:

1. No caso de pedidos menores de 1 ou 2 peças ou reparos ocasionais onde será caro configurar a máquina CNC.
2. Ao projetar e codificar peças ou produtos simples com layouts geométricos simples que não exigiriam programação sofisticada.
3. For cases where an element of human interaction or touch is required for adjustments in the product.
4. When the budget is constrained, and the costs cannot be afforded to purchase the CNC machines outright.
5. It is appropriate for small shops that allow manual control to give a fast reaction.

O que é melhor: Usinagem CNC ou Usinagem Manual para Seu Projeto?

Resumidamente, there is no definitive answer as to what method is better. It all depends on the particular situation at hand. CNC has the advantage of accuracy, mass production, and intricate shapes than the traditional method. The latter is more applicable to the contexts where simple operations, repair, and one-time production are required, with less necessity in terms of precise accuracy as in the case of CNC.

Vantagens e desvantagens da usinagem CNC

The following are the major merits and demerits of CNC machining：

Prós:

High precision and accuracy.

Ideal for complex designs.

The same results or at least, similar results across the various parts of the study.

Use where it is necessary to manufacture large quantities of the same product in a short time.

Consumes lesser manpower once established.

Contras:

High initial investment cost.

This is usually time-consuming, particularly during the initial stages of programming and setting.

Firms therefore are not suitable for one-off or simple jobs.

This one needs expert programmers to set it up.

Limited flexibility once programmed.

Vantagens e desvantagens da usinagem manual

Here are some advantages and limitations of manual machining：

Prós:

1. Lower upfront cost.
2. Meant more for one-time uses or projects that would be completed specifically for one party.
3. Flexibility for on-the-fly adjustments.
4. Simpler setup process.
5. It can be driven with fairly basic levels of abilities but, as one gains more experience, more positive outcomes will be produced.

Contras:

1. Less accuracy in comparison with CNC machining.
2. Less efficiency especially when it is being used for big production runs.
3. Labor-intensive, requiring skilled operators.
4. Lack of uniformity exhibited through various parts of the section.
5. As a fabrication technique, it is not suitable for geometries that are difficult to develop.

Aplicações de usinagem CNC

Então, let’s discuss some of the important applications of CNC machining：

1. Aerospace component manufacturing.
2. Automotive parts production.
3. Printing industry Electronic industry for example production of printed circuit boards.
4. Medical devices and prosthetics.
5. Manufacturing of industrial tools through computer-accurate cuts.

Aplicações de Usinagem Manual

Here are some of the important applications of manual machining：

1. Custom one-off parts.
2. Repair and maintenance jobs.
3. It can also be additional activities, ou atividades realizadas para seu próprio prazer por um ou vários funcionários, como pequenos workshops freelance em casa, ou projetos de hobby.
4. Elementos com pouca complexidade, e portanto, pouca sofisticação na forma de seus contornos ou superfícies.
5. Criação e desenvolvimento dos protótipos antes de iniciar a produção em massa.

Conclusão

Para concluir, na comparação entre usinagem CNC e usinagem manual, ambos os processos de usinagem têm seus usos no mundo da manufatura atual. O que diferencia a usinagem CNC é sua capacidade de precisão, automação rápida, e adequação para grandes produções com designs complexos. No entanto, ainda existem várias indústrias e pequenos trabalhos em que a usinagem manual é benéfica para peças novas, consertar itens quebrados, e outras tarefas semelhantes. The two options in selection depend on the need of the project in terms of complexity, volume, budget, and the level of precision required. When it comes to the balancing of these factors, you will be in a position to select the most appropriate machining method.

perguntas frequentes

1º trimestre. When should I choose manual machining?

Manual machining is best suited for one-off work, small relatively uncomplicated shapes, making repairs, and where frequent changes in dimensions are likely to be required.

3º trimestre. Can I use both CNC and manual machining in a single project?

Sim, it is usual to apply both methods just in case the part to be produced involves a complicated design or is based on the production phases.

4º trimestre. Is CNC machining more expensive than manual machining?

One disadvantage of CNC machines is they are initially expensive. But for massive production, they are cheaper than conventional machines as they reduce labor expenses and speed up operations.

Q5. Can manual machining achieve the same precision as CNC?
While done by hand, manual machining is also accurate as compared to CNC machining but it lacks precision and repeatability.