Have you ever seen a CNC machined part and wondered how they get it to look so perfect? Achieving a premium finish is no easy feat.

Fortunately, with the right technique and tools, anyone can create a stunning surface finish on their CNC machined parts. In this article, we'll cover some of the best surface finishing techniques for CNC machined parts so that you too can create pieces that will be the envy of your peers.

By learning the proper techniques for achieving premium finishes, you'll find yourself one step ahead of other machinists. Not only will you have an impressive looking product to show off, but you'll also be able to take pride in knowing that your work stands out from the rest.

So let's get started and learn more about creating beautiful surface finishes!

Sand Blasting

Sand Blasting

Surface finishing can be a difficult task to complete, especially when it comes to CNC machined parts. It’s like trying to put the final touches on a masterpiece painting; you want to get it just right and make sure that everything looks perfect.

That’s why sand blasting is such an important part of the process. Sand blasting is a media blasting technique which uses small particles, usually made of sand, glass beads or other materials, to create a textured surface finish on the parts being machined. It’s like giving your masterpiece a nice, even coat of paint that will make everything look perfect and shiny.

Sand blasting is an incredibly versatile technique as it can be used for both light and heavy-duty applications. You can use different types of abrasive materials depending on the size and shape of the parts being machined, as well as depending on what kind of surface finish you are looking for.

For instance, if you need a fine finish then you may opt for bead blasting with smaller particles such as glass beads or walnut shells. On the other hand, if you need something more robust then you could use media blasting with larger particles such as sand or grit.



Moving on from sand blasting, polishing is another great option for achieving premium finishes in CNC machined parts.

Polishing has been a popular method since antiquity, used to create intricate finishes and patterns.

While the traditional approach of hand-polishing remains an option, modern technology has allowed us to automate this process to achieve more consistent results.

Micro sanding and vibratory tumbling are two of the most common methods used today.

Micro sanding uses small particles to grind away material and refine surfaces with a high degree of precision.

Vibratory tumbling, meanwhile, uses an abrasive media and a vibratory bowl or barrel to create a smooth finish.

Both these processes can be used on all types of materials, including metals, plastics and composites.

With either technique, you can expect excellent surface finishing results that will last for years.

Painting And Coating

Painting And Coating

Painting and coating are two other popular surface finishing techniques for CNC machined parts. According to a survey, more than 70 percent of manufacturers prefer the use of paint and coating to make their CNC parts look attractive and durable.

Here are some of the most commonly used painting and coating techniques:

  • Powder Coating:
  • This method involves applying a dry powder coating material onto the part using electrostatic methods.
  • The powder is then heated to create a protective, durable finish.
  • Anodizing:
  • Anodizing is an electrolytic passivation process used to increase corrosion resistance, enhance aesthetic appeal, or harden the surface of the part.
  • It involves submerging the part in an acid bath for several minutes to create an oxide layer on its surface.

The choice of painting or coating method depends on factors such as cost, application requirements and desired outcome. It is important to consider these factors carefully before choosing any one method because each offers different benefits for different applications.

Heat Treating

Heat Treatment

After painting and coating, the next step in achieving a premium finish for CNC machined parts is heat treating. This is an essential process that involves controlling the temperature of the metal to create desirable properties.

Heat treating techniques such as tempering and annealing are used to change the physical and chemical properties of the material to make it stronger, more durable, and more resistant to corrosion.

The goal of heat treating is to alter the microstructure of a material, which affects its strength, toughness, and ductility. Depending on the application of the part, different temperatures can be used to achieve various results.

For example, tempering will increase hardness but reduce ductility while annealing may do just the opposite. Knowing what type of treatment should be used for each specific application requires experience and expertise in order to give your parts that premium finish you're looking for.

No matter what type of part you're making or what kind of finish you're trying to achieve, heat treating can play an important role in creating a superior product. It's not something that should be rushed through or overlooked; it's a critical step in delivering a high-quality end result.


When it comes to achieving a premium finish, plating is the gold standard. It's like adding a layer of luxurious jewelry to your already beautiful CNC machined parts.

Plating is the process of covering a product with a thin metal coating, and there are two main types of plating: electroplating and powder coating.

Electroplating is an electrolytic process that involves passing an electric current through a solution containing dissolved metal ions. These ions attach themselves to the surface of the base material and create a thin layer of metal on it.

Powder coating, on the other hand, is a dry finishing technique where powdered particles are applied to the part and then heated up to form an even coat over the entire surface.

Both these processes offer superior protection against corrosion, wear-and-tear, and chemical exposure compared to traditional painting methods.

Both electroplating and powder coating can be used for producing a wide range of finishes from matt black to high-gloss chrome. They also allow for intricate designs as well as smooth surfaces that can be customized according to individual requirements.

And apart from their aesthetic appeal, both these processes have excellent durability and require minimal maintenance over time.

Whether you're looking for an industrial-style look or something more elegant, plating can help you achieve your desired finish with ease and precision.

Laser Etching

Making the jump from plating to laser etching is a big one, but it's worth it. Laser etching involves using a powerful beam of light to engrave an object with intricate details, and it can produce some truly remarkable results. It's also incredibly precise and detailed, making it perfect for achieving premium finishes on CNC machined parts. Plus, its cost-effectiveness makes it ideal for mass production.

But there are other options available too, such as vacuum casting or chemical milling.

Vacuum casting involves creating a mold in a vacuum state using high-grade materials like silicone rubber or polyurethane, which allows you to create precise replicas of complex shapes with incredible detail and accuracy.

Chemical milling is yet another option that uses chemicals to remove material from the surface of a part in order to achieve the desired shape or finish.

Both techniques are ideal for achieving premium finish on CNC machined parts.

No matter what finishing technique you choose, you can be sure that the end result will be stunningly beautiful and highly accurate – perfect for achieving that premium look you're after.


In conclusion, achieving premium finish for CNC machined parts is an art that requires a combination of various techniques.

Sand blasting, polishing, painting and coating, heat treating, plating, and laser etching are some of the best surface finishing techniques.

With these techniques in mind, one can hone their skills to create precision parts with a perfect finish.

It's amazing how far technology has come and how much easier it is now to create high-quality parts with ease!

What a coincidence that we have all these methods available to us today!