Is A Milling Machine The Same As A CNC Machine?

Walking into any metal processing workshop, you are likely to see two scenes at the same time: a seasoned machinist looking over at some old mill’s dial, handwheeling it manually. In another corner, a CNC mill, safety door clamped shut, tooling itself up internally automatically, spindle whirring at high RPM, cutting delicate parts on its own—a textbook CNC milling situation.

Both machines perform “milling,” but are they identical? What is the relationship between sentences “milling machine” and “CNC machine”? In this article, we will clarify this concept in detail and help you make the most educated decision.

Key Answer Summary

Why Is CNC Experience Of The JS Team Important?

Confronting the machining dilemma of intricate CNC milling parts and having no notion if it’s worthwhile to employ manual milling machines or CNC machines, JS’s practical experience could lead you away from potential pitfalls.

JS has received tens of thousands of cases of CNC milling projects in agriculture machine, vehicle parts, and industrial hardware. We offer efficient technical solutions for use from plane simple milling to complex multi-faces boring, one-off customization to batch production tens of thousands of production capacity per year.

This guide is a summary of our more than 10 years of practical experience, and each viewpoint has been validated through actual projects,and can help you decide clearly the right machine for your use.

For professional CNC milling parts solutions, the JS team with its extensive experience of custom cnc milling manufacturing offers full services from design to manufacturing. You simply have to call us to start a project evaluation.

Demystifying The Concepts: Compatibility, Not Opposition

People have a common misconception that milling machines and CNC machine tools are two competing categories of equipment. In fact, they’re complementary. Once you know this, you won’t make the incorrect decisions.

“CNC machine tool” is not a manufacturing company of machines but an abbreviation for computer numerical control system. CNC milling employs such a system to gain precise control over milling operation. When you speak about a “milling machine,” you’re typically referring to the mechanical casing itself.

Correct Relationship: The most fundamental difference between various types of milling machines is the manner in which they are controlled.

The following table here below gives a closer comparison:

Thus, CNC milling machines are a high-tech version of a milling machine. Essentially, it is a matter of “manual operation” versus “numerical control.” CNC milling machines actually put a CNC system into an antiquated milling machine.

Multi-station precision machining workpieces, such as automobile engine blocks, are where CNC milling technology shines at, streamlining the machining process and making it quicker and more accurate.

Core Differences: A True Picture Of Manual And CNC Control

Having now established the relationship between the two, let us go ahead to discuss special differences between manual and CNC control in actual machining. The differences really impact the efficiency of the machining, accuracy of part, and size of production.

Operation and Programming

Hand Milling Machines:

The operator’s skill is the key. During machining, the operator continuously revolves a handwheel in order to control tool travel while monitoring dimensions continuously at every stage. For example, when milling a step surface, feed rate and depth must be varied continuously, relying heavily on the experience of the technician.

CNC Machine Tools:

The core is programming (CAM). The programmer first develops the machining path through the use of computer programs. After the program is entered into the machine, the machine tool will automatically perform actions such as milling, drilling, tapping, etc, without the intervention of a human at every step.

Capabilities and Complexity

Hand Milling Machines:

These are well adapted to conventional features such as planes, steps, right-angle grooves, drilling, and tapping. For parts with complex surfaces or multi-faceted hole systems, such as the curved side of a gearbox housing, it is simply impossible to process.

CNC Machine Tools:

They can machine nearly any geometric shape describable with a mathematical model. Whether complex curved surfaces, inclined holes, or multi-step parts, multi-axis linkage can precision finish them, ideal for the complex machining needs of CNC milling parts.

Precision and Consistency

The difference between precision and consistency of the two machines is apparent from the table below:

If you need to process with high efficiency complex and high-precision CNC milling parts, JS’s milling machine with CNC is able to assist. Our equipment ranges from standard to precision, and we can customize it to suit the specific part requirement so that each product is of quality.

Precision Myth: How Milling Machines Get Multi-Sided Machining

Cumulative error in multi-sided part machining is the largest problem in achieving precision. Traditional milling machines and CNC machine tools approach the issue in entirely different manners with contrasting results.

Fundamental Challenge:

Hand flipping, reorienting, and multi-clamping of workpieces inevitably introduce cumulative error.

For example, in gear casing milling of a gearbox housing, the front face is milled first, the back face must be flipped and milled, followed by side faces. Each clamping action introduces an error of 0.01-0.03mm. With three clamping actions, the cumulative error will be greater than 0.08mm and even high-precision requirements cannot be met.

Safeguards of Traditional Milling Machines (Craftsman’s Wisdom)

In traditional milling, the workpiece is clamped into position using special fixtures by the technicians and, with a dial indicator, brought back into position repeatedly to minimize clamping error.

Technicians also measure after every operation and, through experience, adjust cutting parameters. In cutting a bearing hole, for example, multiple feeds may be used to gradually achieve the desired dimension. However, even when using this approach, the cumulative error of multiple clamping still cannot be completely avoided.

The Problem of CNC Machine Tools (Power of Technology)

CNC machine tools address the accumulated error problem through the “one-clamping, multi-faceted machining” method. For example, in multi-faceted part machining, JS Precision Manufacturing produces special fixtures where all the faces can be machined by the machine through multi-axis linkage after one clamping operation.

Take a vertical machining center for example. It can travel around the X, Y, and Z axes and hence mill front, back, and sides without turning workpieces. Errors are only based on the accuracy of the machine, completely eliminating cumulative errors.

JS offers professional online CNC milling online services. No matter how many sides you need to machine, we can achieve multi-sided machining through single-clamping technology, minimizing cumulative errors and ensuring part precision, saving you from worrying about the quality of machining.

Cost Analysis: Initial Investment Vs. Long-Term Benefits

In choosing equipment, the majority of people take into account only the initial cost of acquisition, not the true costs including labor and efficiency. Cost analysis will help you arrive at a more cost-saving choice.

Purchase Cost

The purchase price of different milling machines is relatively different:

• The purchase price of traditional milling machines (manual milling machines) is $5,000 to $15,000, which is more suitable for individual hobbyists, small workshops, and small batch and simple processing users.
• The purchase price range of CNC milling machines is over $20,000 to $100,000, which is more suitable for users with bulk complex parts processing needs such as enterprises and factories.

Hidden Costs and Return on Investment (ROI)

Labor Costs:

Traditional milling machines require skilled technicians to operate them, who earn approximately $3,000-5,000 per month. A CNC machine programmer is able to program two to three machines, earning around $4,000-6,000 per month, with lower labor costs per machine.

Cost of Efficiency:

Two months are utilized by 500 gearbox housing units using a manual milling machine but just two weeks using a CNC machine. This is five times more efficient, and businesses can do that to acquire additional orders.

Cost of Material and Trial-and-Error:

The wastage of material for manual milling machines is approximately 5%-8%, while that of the CNC is only 1%-2%, conserving loads of material and cash.

Comparison Table of Core Cost Dimensions between Traditional Milling Machines and CNC Machine Tools:

If you are interested in knowing the precise CNC milling price, JS will provide you a detailed cost breakdown. We will determine the cost of manual machining and CNC machining based on part quantities and levels of precision in order to allow you to decide on the most effective form of CNC milling.

Evolution Vs. Replacement: Can I “Upgrade” My Milling Machine?

The majority of companies have traditional milling machines installed and wonder whether to replace them with new ones or to upgrade them. In fact, there are definite answers regarding the replacement relationship between traditional milling machines and CNC machine tools, and the upgradeability.

Can they be replaced by each other?

CNC machine tools can replace traditional milling machines in all their operations, and do them better, faster, and more accurately. For example, in the machining of simple flat parts, CNC machine tools are 3-4 times faster than manual milling machines, and even more precisely.

However, traditional milling machines cannot replace CNC machine tools.For example,CNC milling parts with complex surfaces is out of the range of conventional milling machines.

Can they be upgraded?

Yes! It is a cost-effective and popular solution. By adding numerical control systems, servo motors, and ball screws to traditional milling machines through “numerical control transformation”, they can be upgraded to milling machines with CNC.

JS has retrofitted over 20 companies at a low fraction of 1/3 to 1/2 the cost of a new CNC machine. These retrofitted machines can perform 80% of CNC milling needs, which makes them ideal for cash-starved companies with CNC milling needs.

If you need to upgrade a standard milling machine, JS offers professional CNC retrofitting services, which convert your machine to a productive milling machine with CNC. We also provide custom CNC milling manufacturing services to match your diverse machining needs.

Case Study: Machining Alternatives For JS Power Transmission Housing Components

Background

One small farm equipment manufacturer needed an annual production run of 500 pieces of cast iron transmission housing. The part consisted of three flat surfaces, four bearing holes, and 12 threaded holes. The bearing hole positional accuracy was to be ±0.05mm, and the dimensional consistency deviation was to be <0.03mm.

The customer had been making simple components on a manual milling machine previously. For this particular order, the current solution simply could not provide the levels of efficiency and accuracy and also involved the risk of late delivery.

The customer’s initial solution (Solution A – Drilling Machine + Solely Manual Milling Machine):

Process: Fitter marking -> Milling of big surface -> Flipping, gauging up, milling the second side -> Flipping, gauging up, milling the side -> Drilling holes individually using a jig on drill press -> Tapping.

Pain Points:

• Very low efficiency, 3-4 machine changes per piece of work with a total of 4-5 setups.
• The accuracy in positioning was dependent upon the precision of the jig and the expertise of the technician, which made mass production quite poor in consistency. 2 among 10 pieces were rejected because there was a trial run since accuracy was below par.
• Producing 500 pieces requires 2 manual milling machines, 1 drilling machine, and 2 technicians, taking 2 months and making it impossible to deliver on time.

JS’s Intervention and Solution

After understanding the customer requirement,JS went through the part drawings and appreciated the overall idea of “multi-surface machining in one setup.” We proposed Option B (vertical machining center):

Process:

• Design specialized fixtures that utilizes locating pins and a pressure plate to secure the workpiece so that the entire surface except for the bottom can be machined in a single setup.
• Programmers generate machining paths from CAM software, including milling, boring, drilling, and tapping within one program.
• The machine does the machining automatically, monitoring dimensional precision in real time.

Advantages:

• All operations are completed in a single setup, precision assured by the machine, no built-up error. A trial production of 10 pieces satisfied all specifications.
• The machine can be operated unmanned at night and just one operator can operate two units, increasing total efficiency by more than five times.
• While the initial investment in the vertical machining center is approximately $50,000, spread across 500 pieces, the cost of machining per piece reduces by 35%, and delivery can be done a month and half in advance.

Final Choice

The customer fully adopted JS’s complete solution. From equipment selection, fixture design to programming processing,JS provided one-stop service, allowing the customer to begin production in a matter of weeks.

In just one year, the customer’s investment was repaid many times over through labor and material cost savings and revenue from two subsequent orders. This project has become a benchmark case for JS in the field of agricultural machinery and equipment manufacturing,and equipment manufacturing, and this case is just one of our many custom CNC milling manufacturing projects.

FAQs

Q1: How many operators are needed to run a CNC machine?

Ideally, one programmer would be allocated to two or three CNC machines, and responsible for program preparation, tool changing, and first-article inspection. The operators are largely restricted to workpiece loading/unloading, and machine monitoring, e.g., checking cutting fluid and resolving minor alarms. Small workshops, due to low orders and limited equipment, will tend to have the owner do both programming and operation to keep labor costs down.

Q2: Is CNC machine maintenance particularly difficult and expensive?

Yes, it is more complex than traditional milling machines. Pneumatic, cooling, and filtering systems should be checked frequently, and conditions are stringent (temp 18-25°C, humidity 40%-60%). Large levels of dust can cause guide rails to wear away. However, preventive maintenance guidelines are necessary, as it can identify faults in advance, significantly reduce sudden failures, and avoid high repair costs and production downtime losses.

Q3: Should a used machine tool be purchased?

It is worth it, but the risk is high and needs to be carefully evaluated. It is recommended to have experienced technicians conduct on-site inspections: use specialist equipment to measure spindle runout and platform parallelism, and make test cuts on aluminum alloy parts to assess surface roughness and dimensional accuracy. While buying a second-hand manual milling machine may be less risk-some, there still needs to be lead screw play and spindle quietness in order not to buy gear with worn core parts.

Q4: Is there any compromise for small studios or hobbyists?

There are three compromise options: buy a desktop CNC milling machine (or CNC engraving machine) costing $2,000-$5,000; buy an older-than-five-years machine with a complete maintenance record; or pay $1,000-$3,000 to retrofit an existing manual milling machine to one with a stepper motor and open-source controller. All three options can meet minimal CNC milling needs.

Summary

The interplay between milling machines and CNC machine tools best describes the manufacturing industry’s development from the industrial age to the computer age. Choosing a traditional milling machine is a compromise on cost and simple tasks, while choosing a CNC machine tool is a choice of accuracy, efficiency, and infinite possibilities for the future.

Whether you need equipment selection consultancy, CNC milling parts processing, or upgrading of milling machine with CNC, JS can help you with professional online CNC milling services. We give transparent CNC milling price quotation, simplifying and streamlining the process from solution design and consulting to production delivery.

Choosing JS is choosing a reliable manufacturing partner to help you overcome machining problems and improve cost reduction and efficiency.

Disclaimer

The content of this website is for reference only. JS services expressly disclaims any representations or warranties, express or implied, as to the accuracy, completeness or validity of the information provided. Any performance parameters, geometric tolerances, design features, material specifications or processes mentioned should not be considered as any commitment or guarantee by JS for products offered by third-party suppliers or manufacturers on its network or other channels. Buyers seeking quotes for parts are responsible for confirming their specific needs and product suitability. If you have any questions or need further information, please contact JS directly.

JS Team

JS is an industry-leading companyFocus on custom manufacturing solutions. We have over 20 years of experience with over 5,000 customers, and we focus on high precisionCNC machining,Sheet metal manufacturing,3D printing,Injection molding,Metal stamping,and other one-stop manufacturing services.
Our factory is equipped with over 100 state-of-the-art 5-axis machining centers, ISO 9001:2015 certified. We provide fast, efficient and high-quality manufacturing solutions to customers in more than 150 countries around the world. Whether it is small volume production or large-scale customization, we can meet your needs with the fastest delivery within 24 hours. chooseJS TechnologyThis means selection efficiency, quality and professionalism.
To learn more, visit our website:jsmachining.com

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