Choosing Between CNC Milling and Die Casting for Large Production Runs

For big production jobs, die casting often costs less and works faster than CNC milling. Die casting gives cheaper parts and does the job quickly, especially for tricky shapes. Waltay Electronic Hardware & Plastic Co., Ltd specializes in high volume CNC milled parts, creating exact, custom aluminum pieces for industries that need things to be accurate and flexible.

Key Takeaways

• Die casting works well for making many parts. It costs less and makes the same part quickly.
• CNC milling lets you change designs easily. It is very exact. This makes it good for testing ideas and making small or medium amounts.
• Think about what your project needs. Pick die casting if you need lots of parts and want to save money. Choose CNC milling if you need fast changes or tricky shapes.

Process Overview

High Volume CNC Milled Part Basics

When you pick a high volume cnc milled part, you want accuracy and the same results every time. Cnc machining starts with a digital plan. You turn this plan into steps for the cnc machine to follow. Here is how you make a high volume cnc milled part:

1. First, you use CAM programming and make a cnc program. This step uses software to turn your plan into commands for the cnc machine.
2. Next, you get the machine ready and set up the workholding. You put the material in place, add the cutting tools, and set the coordinates.
3. The cnc machine then does the cutting work. It controls how fast the spindle spins and how the tool moves to shape the high volume cnc milled part.
4. Last, you check the finished part for quality. You use measuring tools to make sure each high volume cnc milled part is correct.

Waltay Electronic Hardware & Plastic Co., Ltd uses advanced cnc machining to make high volume cnc milled part solutions for industries that need things done fast and right.

Die Casting Fundamentals

Die casting is a common way to make lots of parts. You use this process when you need many of the same part quickly. The die casting process has several main steps:

1. First, you make a mould. This mould shapes the melted metal.
2. You get the mould ready for casting.
3. You push hot liquid metal into the mould using high pressure.
4. The metal cools down and gets hard inside the mould.
5. You take the finished part out of the mould.
6. You clean and finish the part to make it look better.

Die casting is good for making tricky shapes and big groups of parts. You get the same results every time and the process is fast, so many companies like to use die casting.

Cost Comparison

Tooling and Setup Costs

When you start a large production run, you need to think about tooling and setup costs. Die casting requires you to make precision molds. These molds can be expensive at first, but you spread the cost over thousands of parts. This makes die casting a smart choice for mass production. CNC milling has lower setup costs. You do not need molds, but you spend more time programming machines and setting up fixtures. If you choose CNC milling for small batches, you save money. For big runs, the cost can rise because you use more material and spend more time on each part.

Several factors affect tooling and setup costs for both processes:

• Equipment and machinery costs can change based on what you need.
• Material selection matters. Harder materials cost more.
• Design complexity can make the process longer and more expensive.
• Production setup includes programming and fixtures.
• Labor costs depend on how skilled your workers are.

Per-Part Cost at Scale

As you increase production, the cost per part drops. Die casting shines when you need many parts. For runs over 10,000 units, you can see per-part costs as low as $0.10. CNC milling also gets cheaper with bigger orders, but die casting usually wins for very large batches. The more parts you make, the less each one costs because you spread the fixed costs.

Here is a quick look at how production volume affects cost:

If you order more than 1,000 parts, you can see the unit price drop five to ten times. This is called economies of scale. Die casting is the best choice when you want to make many parts quickly and at a low cost.

Production Speed

Die Casting Efficiency

You want fast results when you choose die casting for large production runs. This process stands out for its speed and efficiency. Die casting uses high pressure to fill molds with molten metal. The metal cools and hardens quickly, so you get finished parts in a short time. Here are some facts about die casting cycle times:

• Die casting cycles can take only a few seconds or several minutes.
• Zinc parts may finish in as little as 4 seconds.
• High-pressure die casting usually takes between 15 and 60 seconds per part.
• Fast cycles help you produce thousands of parts every day.

You see high efficiency with die casting because the process repeats quickly. You spend less time waiting for each part. This makes die casting a top choice for companies that need speed and consistency. The efficiency of die casting helps you meet tight deadlines and keep costs low.

CNC Milling Turnaround

CNC milling gives you flexibility and precision, but the turnaround time differs from die casting. You do not need special molds, so you start production faster. You can get prototypes in just a few days. Batch production takes a bit longer, but you still see quick results. The table below shows how CNC milling compares to die casting for turnaround times:

CNC milling works well for urgent jobs and design changes. You do not wait for long tooling setup. You get your parts faster, especially for small batches or custom orders. For large runs, die casting offers greater efficiency, but CNC milling gives you speed when you need flexibility.

Precision and Tolerance

CNC Milling Accuracy

CNC machining gives you very accurate parts. CNC machines use computer instructions to shape each part. You can get tight tolerances with advanced CNC systems. If you need small details, CNC machining meets strict rules. The table below shows what tolerances you get with different CNC processes:

CNC machining is good for parts that need exact sizes. It works well for electronics, cars, and machines where details matter.

Tip: Choose CNC machining if you want to control every measurement and need high precision.

Die Casting Consistency

Die casting makes many parts that look the same. The process uses strong steel molds and machines. Here are some facts about die casting consistency:

• Aluminum die casting makes precise parts very fast.
• You can get tight tolerances if you watch the process closely.
• Precision molds copy each part with great detail.
• Alloys like A380 and ADC12 help keep tolerances tight for big jobs.
• Die casting saves time and money because you do not need extra CNC machining or finishing.

Die casting is great for making thousands of matching parts. Careful control of materials, mold design, and process keeps every part within your tolerance limits.

Material Waste

Waste in CNC Milling

CNC milling starts with a solid block of material. The machine cuts away parts that are not needed. This cutting makes a lot of leftover scraps. In big jobs, you might waste between 2% and 5% of the material. Sometimes, if the part is tricky, you can lose up to 95%.

• You have to recycle or throw away the extra pieces.
• Recycling takes more time and work.
• Wasting material can make your costs go up.

To use less material, you should plan your part design well. Picking the best cutting paths helps too. CNC milling is very exact, but you should think about how much material you will lose.

Waste in Die Casting

Die casting uses melted metal poured into a mold. The mold is shaped like your part. This way, you only use the metal you need. There is very little waste. Small extra bits, like the gate and runner, are easy to collect and recycle.

Die casting is good at saving material. You do not have to cut away big pieces. This means you keep more of your metal. Die casting is better than CNC milling for making less waste. You can make thousands of parts with almost no leftover metal. This makes die casting a smart pick if you want to save material and waste less.

Tip: If you want to use less material and make less waste, die casting is better than CNC milling.

Design Flexibility

Complex Geometries

You may need parts with special shapes or features. CNC milling and die casting both help you create complex geometries, but they work in different ways. CNC milling uses cutting tools to shape metal. You can make detailed surfaces, sharp corners, and custom features. Sometimes, you need to run the machine several times to finish a very complex part. Die casting uses molds to form metal. You can create air pockets and cavities in one step. This process works well for parts with hollow sections or thin walls.

Here is a table that shows what each process can do:

Tip: If you want a part with many internal spaces or thin walls, die casting may be the best choice. If you need sharp details or custom surfaces, CNC milling gives you more control.

Design Changes

You may need to change your design after you start production. CNC milling gives you more freedom. You can update your digital plan and start making new parts right away. You do not need to wait for new molds. This saves you time and money.

• CNC milling allows for immediate processing after design updates without the need for molds, making it more flexible for design changes.
• Die casting requires molds, and any design changes lead to increased costs and delays in production.
• Machining can deliver prototypes in weeks, while die casting tooling requires 20-25 weeks.
• Individual machined parts may be more expensive than cast parts, but die casting involves a significant upfront tooling investment.

You can test new ideas quickly with CNC milling. Die casting works best when your design is final and you need many identical parts.

Scalability and Suitability

When to Choose High Volume CNC Milled Part

You should choose high volume CNC milled parts when you need flexibility and fast changes. CNC milling works well if your design might change or if you want to test new ideas. You do not need to wait for expensive molds. You can update your digital files and start making new parts right away. Waltay Electronic Hardware & Plastic Co., Ltd can deliver rapid, customized CNC parts for urgent or complex needs. This makes CNC milling a smart choice for prototypes, small-to-medium batches, or when you want to keep your options open.

• CNC milling is adaptable for design changes.
• You get quick updates without extra tooling costs.
• It suits projects where you need high precision or unique features.
• You can scale up for moderate production runs.

Tip: If you expect your design to change or need parts quickly, CNC milling gives you the flexibility you need.

When to Choose Die Casting

Die casting is the best choice when you want to make thousands of identical parts. The process needs a big investment in molds, but you save money on each part as you make more. Die casting works best when your design is final and you want to keep costs low for large production runs. You get fast, repeatable results and very little waste.

• Die casting is cost-effective for stable, high-volume production.
• It is less flexible for design changes but great for making many parts fast.
• You should discuss scalability with your manufacturer early.

Note: If you plan to produce thousands of parts and want the lowest cost per part, die casting is the way to go.

Decision Guide

Checklist for Process Selection

You need to pick the best process for your project. A checklist helps you compare CNC milling and die casting step by step. This guide helps you match your needs with the right method.

Key Criteria to Consider:

Simple Checklist for Your Decision:

• Do you need a small batch or prototype?
  • ✅ Pick CNC milling.
• Do you want to make thousands of parts?
  • ✅ Pick die casting.
• Will your design change during production?
  • ✅ CNC milling lets you change designs fast.
• Do you want the lowest cost per part for big runs?
  • ✅ Die casting saves more money at scale.
• Do you need strict tolerances or a special surface finish?
  • ✅ CNC milling gives better precision and finish.
• Are you using materials like steel or titanium?
  • ✅ CNC milling works with more material types.

Tip: Use this checklist to compare what your project needs. If you are not sure, ask an expert early. Waltay Electronic Hardware & Plastic Co., Ltd can look at your CAD files and help you pick the best process.

Application Matching

You can match your project to the right process by looking at common examples. The table below shows when to use CNC milling or die casting.

Expert Recommendations for Your Project:

• Use both processes if you want your design to stay the same from start to finish.
• Make your workflow simple to avoid using many vendors.
• Pick materials that are easy to cut and shape, like aluminum alloys, for fast machining.
• Choose strong materials, like titanium or high-grade aluminum, if your parts need to be tough.
• Think about your surface finish. Aluminum and brass can look smooth easily.
• Balance your budget with your quality needs. Plastics and alloys can help save money.

Action Steps for a Successful Project:

1. Talk to engineers early. Share your CAD files to see if your design fits CNC milling or die casting.
2. Ask for help picking the best materials and process for your part. Aluminum 6061 and zinc Zamak are good choices.
3. Use in-house finishing services, like bead blasting or anodizing, to get a smooth look.

Note: Every project is different. You get the best results by working with a team that knows CNC milling and die casting. Waltay’s experts can help you from design to delivery.

Die casting saves you money and time when you make many parts. It is the best choice for big jobs with lots of finished pieces. Use the decision guide to help pick what you need for quality, accuracy, and speed. You can ask Waltay for help or get a special price.

FAQ

What is the main benefit of CNC milling for large runs?

You get high precision and flexibility. CNC milling lets you change designs quickly and produce parts with tight tolerances.

How fast can die casting produce parts?

Die casting can make thousands of parts each day. You see cycle times as short as 15 seconds per part.

Which process creates less material waste?

You save more material with die casting.