Surface Finishes for CNC Machining
We offer a variety of surface finishing methods, both in-house and through our supplier network, to improve your part's durability, surface finish, and aesthetic appearance.
Surface Finishing Options for CNC Machined Parts
A machined component's surface finish is crucial when it interacts with other components.
Take a ball bearing for example. They are designed to minimize rotational friction and support loads. As the races rotate, the balls also turn due to their contact. If the surfaces of the balls or races are not finished correctly, friction increases, leading to more wear and a shorter lifespan, even if the components meet geometric tolerances.
It is worth noting, though, that there is a difference between surface finish and surface finishing. The table below describes th various surface finishing methods that we offer both in-house and across our supplier network.
Check out our knowledge base article for more information about the differences between surface finish and surface finishing methods.
| Description | Compatible Materials |
In-House |
Network |
|
| Anodize Type II |
An electrochemical process that forms a moderately thick, corrosion-resistant oxide layer that improves your part’s durability Applied with: media blasting, tumbling, chem film |
Aluminum Titanium |
X | |
| Anodize Type III |
A thick, dense anodic coating, also known as hardcoat anodize, that’s applied to aluminum to improve wear resistance, corrosion protection, and electrical insulation Applied with: media blasting, tumbling, chem film |
Aluminum |
X | |
| As Machined |
A standard finish with edges deburred and visible toolmarks Applied with: -- |
Metals Plastics |
X | |
| Bead Blast |
A mechanical finishing process that uses spherical media (i.e., glass or ceramic) to gently polish a surface, imparting a smoother finish with minimal material removal Applied with: all post processes, except electropolish and powder coat |
Metals Plastics |
X | |
| Conversion Coating |
A chemical surface treatment that transforms the metal substrate into a thin, corrosion-resistant layer without adding significant thickness; common types include chromate, phosphate, and oxide coatings Applied with: media blasting, tumbling, Type II anodize, Type III anodize with PTFE |
Aluminum (chromate) Steel (phosphate) Mild steels (oxide) |
X | |
| Deburring |
A mechanical finishing process used to remove sharp edges, burrs, or residual material from machined parts using tools like files, blades, or abrasive pads Applied with: -- |
Metals Plastics |
X | |
| Dry Ice Blasting |
A non-abrasive cleaning process that uses compressed air to accelerate dry ice pellets that sublimate on impact to lift contaminants off the surface without leaving a residue or damaging the part Applied with: -- |
Metals Plastics |
X | |
| Electroless Nickel Plating |
A chemical process that deposits a uniform layer of nickel-phosphorus alloy onto a substrate without using electricity, offering excellent corrosion resistance, wear protection, and consistent coverage even on complex geometries Applied with: media blasting, tumbling |
Aluminum Steel |
X | |
| Electropolish | An electrochemical process that removes a thin layer of metal from a part’s surface to improve smoothness, brightness, and corrosion resistance |
Stainless Steel |
X | |
| Grit Blast |
A cleaning and texturing process that uses abrasive particles (i.e., aluminum oxide or silicon carbide) to impart a rougher, matte finish that’s ideal for coating adhesion or mechanical bonding Applied with: -- |
Metals |
X | |
| Laser Mark |
Add labeling, logos, and/or other text to your parts Applied with: -- |
Metals Plastics |
X | |
| Passivation |
A non-electrolytic process that uses nitric or citric acid to remove free iron from metal, create a protective oxide layer, and prevent corrosion Applied with: black oxide, electroless nickel plating, zinc plating, tumbling, media blasting |
Metals |
X | |
| Powder Coat |
A dry finishing process where finely ground pigment and resin particles are electrostatically charged and sprayed onto the part’s surface, then cured under heat to form a durable, uniform, and protective coating Applied with: -- |
Metals |
X | |
| Vibratory Deburring |
Parts are placed in a rotating barrel with abrasive media to achieve smooth edges and finish Applied with: all post processes, except electropolish and powder coat |
Metals Plastics |
X |
CNC Machining Materials
CNC Machining FAQs
What industries do you support?
Hirsh has a long history of supporting the industrial, automotive, aerospace, medical device, biotechnology, and scientific instrument sectors.
What tolerances can you hold?
General tolerances on metals can be held to +/- 0.005" (+/- 0.127 mm) in accordance with ISO 2768 unless otherwise specified. Plastics and composites can be +/- 0.010”.
Hirsh can also machine and inspect to tight tolerances, including sub +/- 0.001" tolerances, per your drawing specifications and GD&T callouts.
Can you assist with design optimization for machining complex parts?
Yes, in fact, it’s our team’s preference that we support your part’s production with DFM before moving into production.
Our DFM is most effective when it’s requested before a design is finalized. We can still provide design optimization feedback even after a design has been finalized, though. Contact our team as early in the manufacturing process as possible to achieve the biggest time and cost savings.
How can I request a quote from Hirsh?
Easy! Just submit an RFQ through our website.
What file formats do you accept for part uploads?
We accept STEP, STP, SLDPRT, IGS, X_T, PDF, JPG, and PNG file formats.
For the fastest turnaround time on quotes, please include both a CAD model and a detailed, reviewed technical drawing for each part that you want quoted. This enables our team to build a comprehensive quote and move into production as quickly as possible.
What machining capabilities do you have?
Milling: 3-, 4- and 5-axis CNC milling options for your most complex and intricate components
Turning: Swiss and multi-turret turning centers with live tooling and barfeeders to support lights-out production.
Flexible Manufacturing Solutions: two Fastems systems, seven 5-axis mills and over 100 pallets to support production in the 100s and 1000s; reduced setups and shorter cycle times improve quality and cut down on costs.
Here is a comprehensive list of our CNC machines.
What types of materials do you machine?
We work with a wide variety of metal and plastic materials, including medical-grade plastics.
Explore the Material Index to learn more about the types of metals and plastics we machine.
What finishing options are available for machined components?
Hirsh offers a range of surface finishing methods, both in-house and through our supplier network. These finishing options are designed to improve your part’s durability, finish, and aesthetic appearance.
Here is a full list of our surface finishing options for CNC machined parts.
Can you assemble parts at your facility?
Yes, we offer both mechanical and electro-mechanical assembly services.
What certifications or industry standards do you adhere to?
Hirsh Precision is ISO 13485 and AS9100 certified, and our QMS is compliant with ITAR, EU REACH, EU RoHS, and EU CMRT.
Our approved manufacturing partners also adhere to a variety of industry standards, including: ISO 9001, ISO 13485, ISO 14001, AS9100, IATF 16949, and NADCAP.
Learn more about Hirsh’s approach to quality.
What inspection options do you offer?
We offer several different inspection options, including a standard FAIR, a certified inspection report (CIR), AS9102C FAIR, APQP, PPAP, and SPC.
You can read more on our Quality page.
What metrology equipment do you have?
Hirsh maintains a wide range of inspection technology and equipment, including many CMMs, multiple styles of visual inspection systems, in-house calibration for hand tools and gages, and “Z” class gage pins at every machining center.
Let's connect
Want to learn more about our CNC machining services? Schedule a time to speak with our team.