Save 35% on Costs Precision Cnc Steering and Milling Services Optimize the Production of Industrial Equipment Parts
Figure 1: Understanding the fundamental differences between CNC Turning and Milling is the first step to selecting the right process for your industrial parts.
Introduction
Industrial equipment companies that are faced with the challenge of low volume manufacturing of Custom Parts are usually caught up in a dilemma. In-house manufacturing could be too expensive and time-consuming, while outsourced manufacturing could lead to quality control issues and delivery times. The challenge associated with low volume manufactured custom parts could lie in a misplaced correlation of part attributes with a suitable precision manufacturing technique and a lack of manufacturing insight at the design level, resulting in downstream processing difficulties and expenses.
In this explanation, an in-depth comparison of Precision CNC Turning with CNC Milling and Turning services would address how Design Optimization at a early stage of design could provide a harmonious blend of quality, expenses, and lead times. In order for a correct choice to be made, an awareness of the basic distinctions between the two mentioned services is a priority.
Precision CNC Turning and CNC Milling – What Are the Fundamental Differences?
Choosing an appropriate CNC process is the beginning of a successful project. Though both processes involve subtraction in manufacturing, they have different concepts.
Basic Principles and Definitions
The CNC turning process is mainly used for making rotational components. The process involves the rotation of the raw material at high speed while the cutting tool moves radially or axially to remove the material, thereby creating components such as cylinders, cones, threads, and so on. The process is useful for manufacturing shafts, pins, bushings, and flanges.
On the other hand, CNC milling machining is used for components that have complicated contours. In this case, the cutting tool is rotated rapidly, and the material is fixed on the moving table. This makes it possible for the mill to produce planes, grooves, complicated surfaces, or irregular holes, and it is often used for machining plates, enclosures, or brackets.
A Helpful Analogy
This contrast may be better understood by a simple example: Precision CNC Turning is like the “use of a potter’s wheel,” where the craftsman turns the wheel with the clay to create a balance shape. CNC Milling is more like the “sculptor,” where the sculptor uses various chisels (rotating mill) to chisel the details on the stationary or moving block of material. The turning is very efficient in circular cuts, while the mill has the flexibility to shape the material in multiple directions.
Technical Comparison: Axes and Toolpaths
The basic differences in axes of motion and tool motion determine their capabilities.
- Axes of Motion: A simple turning center requires motion in 2 axes (X and Z), whereas milling requires at least 3 axes (X, Y, and Z). More advanced machinery for machining might require 4 to 5 axes.
- Movement of the Tool and the Workpiece: The major movement in turning is the rotation of the workpiece, while the tool moves in a linear manner. Additionally, in milling, the major movement is the rotation of the tool, in which the workpiece or tool moves in several directions.
- Resulting Geometries: Turning is suited for making external diameters, internal bores, faces, and threads. Milling is suited for making flat surfaces, pockets, hole arrays (non-round holes), and chamfers.
Based on categories created by respected organizations, such as the Society of Manufacturing Engineers (SME), turning and milling can be considered complementary processes. However, for individuals who find it difficult to make a choice, being able to identify the importance of choosing between precision CNC turning and CNC milling services based on geometric characteristics of the components would be essential.
Figure2: Follow this decision flowchart to quickly identify the most suitable and cost-effective CNC process for your specific part geometry.
How to Choose the Best Process for Your Industrial Equipment Components?
The choice between the appropriate process for the components in Industrial Equipment involves an analysis that requires consideration of certain objective aspects.
Clear decision paths begin with part geometry. For example, if the geometry of the component in question comprises basically a rotational solid, think cylinder and cone, the choice would be high precision CNC turning services, e.g., transmission shafts, pistons, and sleeves. Others, if they feature complex contours, multiple flat areas, and irregular holes, would find CNC milling a better option, e.g., equipment guards, valve bodies, and brackets.
Other factors that need consideration later are material, tolerance, and production batch size. For example, a high-strength alloy steel shaft that demands accurately made bearing seats with high roundness and surface finish is suited to turning operations only. However, when complex components need a combination of rotational and milled components, then CNC Milling and Turning combined within a single machine is most appropriate.
Lastly is the importance of the supplier’s credentials. The choice of a company that has the best certifications in the industry such as IATF 16949 for the automotive industry or AS9100D for aerospace attests that the quality management system can address the high requirements of the industry in terms of overall quality.
How Does Design Optimization Unlock Maximum Value in Precision Manufacturing?
Excellence in manufacturing starts with excellence in design. Where DFSoM focuses on cost-effectiveness, Design for Manufacturability (DFM) essentially translates to cost control, which becomes very important with Low-Volume Production.
A great deal can be accomplished with basic rules with precision CNC turning parts, precision machining, and related machined products.The MEP principles that are most desirable for DFM are the following:
- Avoid sharp corners inside the component.
- Standardize or maximize the inside radii of features with weld fillets to accommodate standardized tools.
- Smoothen the profiles of the component. It is desirable to standardize the sizes for equivalent features to minimize the number of tools to be changed.
In Low-Volume Production, a modular design philosophy is highly advisable. Complex assemblies can be broken down into various standard pieces that require assembly, thereby making custom component designs less expensive and less difficult to accomplish.
For instance, a part that has a non-standard, deep undercut might require a special tool and operations. This particular case could be improved by altering the depth to that of a standard part and accepting higher tolerance values on the surfaces that do not affect functional performance. This might enable an increased machining speed and lower cost by more than 20%. Standards from organizations such as the American Society of Mechanical Engineers (ASME)provide these kinds of best practices.
Role of a High Precision CNC Turning Center on Part Consistency
In the case of critical components such as the shaft of a servo motor or the spools of hydraulic valves, it is as much the goal to have consistency as it is to achieve absolute accuracy. It is precisely this benefit that is offered by the use of a high precision CNC turning center.
Modern CNC machines have achieved micron levels of repeatability using robust machine beds and spindles to damp vibration, intelligent thermal compensation systems to compensate for deformations, and sophisticated CNC controllers with feedback systems to guide precise movement of the tool. The benefit is that variation in important dimensions for the first and hundredth product is negligible.
Such levels of consistency are the basic foundation for the interchangeability of parts as well as the dependable operation over time of industrial equipment. This step addresses the basic requirement for a quality management system such as ISO 9001 for process control and the prevention of variation, and an investment in a technologically advanced partner will certainly pay off for the quality of the products.
How to Effectively Control Cost and Lead Time in Low-Volume Production?
Low-Volume Production Management Economics calls for a specialized approach that recognizes the specific factors influencing costs and techniques to speed up time, different and different from that of high volume production.
Analyze and Optimize the Cost Structure for Low Volumes
The cost of the Custom Parts made at a low volume also has expenses other than the material and the machine time. This includes the fixed costs that are amortized over the entire production. This is crucial to make the costs economic.
- Understanding the Cost Composition:
Key cost drivers include initial CAM programming, custom fixture/jig design, and the cost of setting up each operation. For small batches, the fixed costs are apportioned to a smaller number of units, which results in a substantial increase in the cost per unit compared to large-scale production. - Execution of Smart Saving Strategies:
Some effective strategies to counter this are the use of available standard stock materials, the design of parts for usage with universal or modular fixtures, and cooperation with the supplier to loosen non-critical tolerance specifications. This will enable faster machining speeds.
Leverage Digital Tools to Compress Lead Times
Rapid prototyping or parts production requires speed. One major technique that can be adapted here is digital supply chain engagement. Online direct quoting platforms enable manufacturers to examine their CAD designs directly, pick out areas that impede manufactureability, and produce quotes in mere hours. This can take weeks with conventional methods.
Work with a Competent and Attentive Supplier
Having a direct influence on reliability is the selection of the manufacturer. Whether or not a supplier holds qualifications such as ISO 14001 indicates whether it has organized processes that are efficient and also help ensure reliability. In the end, having a responsive manufacturer with the right capabilities related to CNC turning services is an important step in achieving success.
Conclusion
In closing, where a Low-Volume Production project is concerned specifically with the manufacture of parts for industry-grade equipment, a careful identification and allocation of part characteristics relative to either CNC turning or milling, or even a combination of both machining techniques as part of Design Optimization strategies, is crucial. Adopting this particular approach has a direct correlation with realizing cost savings and shortened market time.
Have the next project for a custom part been considered? Upload your CAD file now and get an instant quote and see the power of precision manufacturing firsthand.
Author Bio
This article was contributed in collaboration with an engineering expert having over a decade of experience in high-precision manufacturing. The expert’s team, with many years of extensive industry expertise with leading suppliers such as JS Precision, aims to provide cutting-edge, reliable, and competitively priced machining solutions for industrial equipment manufacturers across the world.
FAQs
Q1: In what ways do CNC Turning and CNC Milling differ in their applications?
A1: Turning intended for rotational components like shafts and sleeves, focusing on efficient and circular products. Milling suitable for plates and cases requiring intricate shapes and holes.
Q2: Can CNC machining for small-batch orders (less than 100 pieces) be economical?
A2: Yes. In terms of strength, surface finish, and materials available for small production runs without mold cost, CNC machining has an edge over 3D printing technology. The overall cost can become more favorable.
Q3: How to make sure that the precision of the parts made by the CNC machine meets the drawing specifications?
A3: It is crucial to choose a supplier with high-precision machinery and a quality management system. The supplier can conduct first-article inspection and in-process inspection using CMMs and follow quality management systems such as ISO 9001.
Q4: Are there any design principles which can lower the cost of CNC machined parts?
A4: Generally applicable principles include minimizing setup time, avoiding holes that are very deep or unsupported spans, standardized tool size, relaxed tolerances when not critical, and machineability.
Q5: When is CNC Milling and Turning (combined machining) applicable?
A5: This is ideal where the component involves features that can be turned, for example, outer diameters, and milling features, for example, side holes and keyways. All these can be done in one operation on one machine.
