What is Precision Machining?
Machining is a subtractive manufacturing process used in the production of parts. It entails removing material from a workpiece with a cutting tool until it takes the shape of the final design.
In a nutshell, precision Machining covers the design, fabrication, and measurement of high-accuracy components. It is machining done while maintaining close, tight, well-controlled tolerances.
Materials Used in Precision Machining
Precision Machining is suitable for a wide range of materials. These materials include metals like bronze, aluminum, steel, etc. It can also be used on materials like plastics, foam, polystyrene, crystals, etc.
Types of Precise Machining Processes at RapidDone
Depending on the level of precision needed, there are different types of machining processes we use in our shop. To finish high-precision parts, we will use one of them or several of them at one time.
√ CNC Milling
CNC Milling is a machining process that removes the metal by advancing a rotary cutter into the workpiece. The axis of the workpiece and the milling machine are moveable to create 3D patterns.
√ CNC Turning
CNC Turning involves using a lathe to rotate the workpiece against a stationary cutting tool. As the workpiece moves against the cutting tool, it removes the excess material. The machine’s controller can move the cutting tool along the workpiece’s axis to create the required patterns.
√ CNC Grinding
CNC Grinding involves removing small amounts of materials via a high-speed abrasive wheel or flat board. It can get a very tight tolerance for cylindrical features or flat features. It is a very popular process for high-precision shaft parts.
√ Swiss Machining
It involves using a high-precision lathe called a Swiss-type Lathe to create small parts accurately. In Swiss machining, the component is held firmly in the headstock while various tools cut away the metal. This gives it more precision and stability than a regular lathe.
√ Single Point Diamond Turning
It is just like CNC turning, only that a diamond-tipped tool replaces the cutting tool. The diamond-tipped tool provides a better surface finish and accuracy than the lathe cutting tool.
√ Electro-Discharge Machining
In Electro-discharge machining, the metal is removed using an electric spark. It involves applying a high-frequency current to the workpiece. The current erodes the workpiece’s surface little by little, forming the desired shape.
√ Ion Beam Machining
Ion beam machining finds most of its applications in nanomanufacturing. It entails bombarding the material’s surface using an accelerated ion stream to remove materials at the atomic level. It produces precise and highly accurate parts.
Precision Machining Tolerance
Based on our manufacturing experience, there are different Precision Machining operations available, and they all produce different levels of accuracy.
| Process | Tolerance |
| √ CNC Turning | 0.005” |
| √ CNC Machining | 0.005” |
| √ Swiss turning | 0.0006” |
| √ Electro-Discharge Machining | 0.0001” |
| √ Ion Beam Machining | 0.0000002” |
Applications
Tight tolerance machining is employed in applications where tight tolerances and low surface roughness are key. For machines that comprise several small mating components, these factors are important for a proper fit. Also, precision machining finds applications in the restoration or repair of tools. For example, when cleaning the rust or oxidation build-up off a tool or component’s surface. Many industries currently use precision machining.
- Aerospace Industry
- Energy Industry
- Electronic Industry
- Defense Industry
- Medical Industry
Advantages
Precise Machining has many advantages over other manufacturing methods.
It unlocks so many capabilities for your product.
√ It Eliminates “Fitting” and Provides Automatic Assembly:
Often, mating parts need to be filed, heated, or even forced onto each other during assembly. Fitting activities like this can have adverse effects on the components. Precision Machining eliminates all these by ensuring a smooth, seamless fit at all times.
√ It Improves the Interchangeability Of Parts:
Precision machined parts are highly interchangeable. They can replace an existing component in an assembly seamlessly without the need for any custom fitting.
√ Greater Miniaturization and Complexity is Achieved:
As technology becomes more advanced, interest in microtechnology is increasing. Parts required for applications like this must adhere to the highest of standards. Only Precision Machining processes can produce parts that can match up to these standards.
FAQs
Q1: Which Precision Machining Process is the Best?
A: Technically, the most accurate precision machining method is Ion Beam Machining. But that is too expensive and technical for most commercial applications.
At RapidDone, we recommend the best Precision Machining method to our customers based on their precision needs and budget. In this way, we can balance cost and quality.
Q2: What Finishes Can Be Applied To Precision Machined Parts?
A: When it comes to finishes, product designers have to be cautious. Most commercially available surface finishes can ruin the accuracy and tolerances of precision parts.
However, some finishes are still compatible with precision parts. They include Electropolishing, Laser engraving, Honing and Lapping, Vibratory finish, etc.
Q3: What is the Relationship Between Tolerance and Cost?
There are different levels of accuracy attainable in Precision Machining. The precision the customer requires influences a whole lot in the cost department. It determines the machining process used, the sort of labor employed, and even the consumables’ cost. All these factors cost differently for different precision Machining processes. As you can imagine, the more precision you require, the higher the price.
Q4: How to Choose the Best Precision Machining Vendor
Choosing a vendor or a machine shop can be difficult due to the number of options available, we can compile the below metrics:
√ Cost: Precision machining can be a very costly activity bearing in mind the quality it delivers. Sometimes, it might be tempting to get the job done at cut-rate prices, but this can have adverse consequences.
To get the best cost estimate, try to get multiple quotes and confer with their engineering teams. Getting the best information around will help you figure out how to balance cost with quality.
√ Staff: The quality of the personnel matters a lot. A machine shop that employs high-quality professionals can be counted upon to deliver the best results.
So when selecting a vendor, look for one that emphasizes hiring the best talent. Not only that, but look for firms that engage in continuous worker education to keep up with advancements in the field.
√ Machines: Machinist is only as good as the equipment they have at their disposal. A shop floor stocked with great machines will enhance the abilities of the machinist. This synergy will enable the vendor to churn out top-quality results.
√ Precision Requirement: The precision requirements of the project should also affect the type of vendor selected. As we mentioned earlier, different grades of precision require separate processes and infrastructures. So, before you choose a vendor, be sure that they can handle the project.