Micro CNC Machining Services
Micro CNC machining at FIRMFG produces miniature precision parts with feature sizes down to 0.1mm and tolerances to ±5µm. Our capabilities include micro milling, micro turning, 5-axis micro machining, and micro drilling for medical, aerospace, electronics, and optics applications. ISO 9001 certified. Get a quote in 24 hours.
Micro CNC Machining Services: Miniature Precision Parts from 0.1mm Features
Micro CNC machining at FIRMFG bridges the gap between conventional CNC precision and the microscopic world. Using miniature cutting tools as small as 0.1 mm in diameter on high-speed, high-resolution machines, we produce functional parts with feature sizes below 1 mm and dimensional tolerances down to ±5 µm (±0.005 mm). Our micro machining capabilities span micro milling, micro turning, 5-axis micro machining, and micro drilling — covering the full range of micro manufacturing needs from prototype to production.
At the micro scale, conventional machining rules break down. Material behavior changes due to size effects — grain size becomes comparable to feature size, cutting forces shift, and thermal management becomes critical. Our micro machining facility is equipped with spindles running up to 150,000 RPM, nanometer-class control resolution, and temperature-stable machine structures designed specifically for micro-scale precision. Every micro part is inspected with white light interferometry, optical CMM, or scanning electron microscopy (SEM) to verify features that are invisible to the naked eye.
FIRMFG serves industries where miniaturization drives innovation: medical devices (bone screws, implants, surgical instruments), aerospace (turbine cooling holes, fuel injector nozzles), electronics (micro connectors, heat sinks), optics (micro lens molds, fiber ferrules), and defense (fuse components, micro sensors). Our ISO 9001:2015 certified quality system ensures every micro part meets specification, with 100% inspection on critical features and full dimensional reports included with every order.
This guide covers everything you need to know about micro CNC machining — capabilities, processes, minimum feature sizes, materials, tolerances, applications, challenges, and supplier selection. Use it as a reference when designing your next micro part, or skip ahead and request a quote for an immediate price and lead time.
What Is Micro CNC Machining?
Micro CNC machining removes material at the micrometer scale using miniature tools on ultra-precision machines. It is defined by feature sizes below 1 mm and tolerances measured in single-digit micrometers.
Micro CNC machining is a subtractive manufacturing process that uses cutting tools with diameters between 0.1 mm and 1.0 mm — ten to one hundred times smaller than conventional CNC tools — to machine features measured in micrometers. The process operates on the same fundamental principle as conventional CNC machining (rotating cutting tool removes material from a workpiece), but the scale reduction introduces physics that fundamentally change how material is cut.
At conventional scale, the cutting edge removes material that spans many material grains. At micro scale, the uncut chip thickness approaches the grain size of the material, and the cutting edge radius becomes comparable to the chip thickness. This phenomenon — known as the size effect — causes specific cutting energy to increase dramatically as feature size decreases. Material no longer behaves as a homogeneous continuum; instead, individual grain boundaries, crystallographic orientation, and defects dominate cutting behavior. The result is higher cutting forces per unit volume, accelerated tool wear, and surface finishes influenced by material microstructure rather than tool geometry alone.
The Size Effect
When the uncut chip thickness drops below the material grain size (typically 10–100 µm for metals), cutting enters the micro regime. Specific cutting energy rises 2–5×, tool-edge radius dominates chip formation, and material heterogeneity causes force fluctuations. Understanding the size effect is essential for selecting cutting parameters in micro machining.
Minimum Chip Thickness
Below a critical chip thickness — typically 20–30% of the tool edge radius — the tool plows and rubs rather than cuts. This minimum chip thickness effect limits how small a feature can be machined and drives surface finish in micro machining. Sharper tools (smaller edge radius) reduce the minimum chip thickness and enable finer features.
| Parameter | Micro CNC Machining | Conventional CNC |
|---|---|---|
| Spindle Speed | 20,000 – 150,000 RPM | 8,000 – 24,000 RPM |
| Tool Diameter | 0.1 – 1.0 mm | 3 – 25 mm |
| Tolerance | ±0.002 – ±0.005 mm | ±0.02 – ±0.05 mm |
| Control Resolution | 0.1 µm (nanometer-class) | 1 – 5 µm |
| Typical Workpiece Size | < 50 × 50 × 50 mm | Up to 1000 × 600 × 500 mm |
| Chip Load per Tooth | 0.5 – 5 µm | 0.02 – 0.5 mm |
| Surface Finish | Ra 0.05 – 0.2 µm | Ra 0.4 – 1.6 µm |
The order-of-magnitude differences in every parameter explain why micro CNC machining requires dedicated equipment. A conventional CNC mill retrofit with small tools cannot achieve micro precision — the spindle speed, control resolution, and structural rigidity are all insufficient.
Micro CNC Machining Capabilities
FIRMFG's micro machining facility combines high-speed spindles, nanometer-class control resolution, and specialized tooling to achieve feature sizes and tolerances impossible on conventional CNC equipment.
| Capability | Specification |
|---|---|
| Minimum Feature Size | 0.05 mm (50 µm) |
| Tightest Tolerance | ±0.002 mm (±2 µm) |
| Standard Micro Tolerance | ±0.005 mm (±5 µm) |
| Surface Finish (Best) | Ra 0.05 µm (mirror finish) |
| Maximum Spindle Speed | 150,000 RPM |
| Positioning Accuracy | ±0.5 µm (full travel) |
| Repeatability | ±0.3 µm |
| Minimum Tool Diameter | 0.1 mm (micro end mill) |
| Minimum Hole Diameter | 0.05 mm (micro drilling) |
| Minimum Internal Radius | 0.025 mm (25 µm) |
| Max Depth-to-Diameter Ratio | 10:1 (drilling) / 5:1 (milling) |
| Quality Standard | ISO 9001:2015 Certified |
±0.5 µm Positioning
Nanometer-class linear scales and hydrostatic guideways deliver positioning accuracy of ±0.5 µm over full machine travel, enabling feature placement to single-digit micrometer precision.
150,000 RPM Spindle
High-speed air-bearing spindles reach 150,000 RPM, providing the cutting speed needed for 0.1 mm tools while maintaining sub-micron runout for clean micro features.
Ra 0.05 µm Finish
Mirror-quality surface finishes down to Ra 0.05 µm are achievable with diamond tooling on non-ferrous materials, eliminating secondary polishing for optical and fluidic applications.
0.05 mm Min Feature
Micro drilling produces holes as small as 0.05 mm (50 µm) in diameter, while micro milling creates slots and walls down to 0.1 mm — features invisible without magnification.
Micro Machining Processes
FIRMFG offers four core micro machining processes, each optimized for specific feature types, geometries, and materials. Selecting the right process is critical for achieving required precision at optimal cost.
Micro Milling
Tool diameter: 0.1 – 1.0 mm
Micro milling uses ultra-fine end mills — as small as 0.1 mm in diameter — to create micro channels, micro cavities, thin walls, and intricate 3D contours. Running at spindle speeds up to 150,000 RPM, micro milling achieves surface finishes down to Ra 0.05 µm while maintaining dimensional accuracy to ±5 µm. The process is ideal for producing microfluidic devices, micro molds, and miniature mechanical components.
Typical Applications
Micro channels, micro cavities, thin-wall structures, micro gears, mold inserts
Micro Turning
Tool diameter: 0.1 – 0.5 mm insert
Micro turning produces cylindrical micro components such as micro shafts, micro pins, and micro optical elements on precision Swiss-type lathes. With diamond inserts and sub-micron positioning resolution, micro turning achieves diametrical accuracy to ±2 µm and surface finishes suitable for optical applications. The process excels at producing long, slender parts with high aspect ratios that would deflect under conventional cutting forces.
Typical Applications
Micro shafts, micro pins, micro threads, optical lens housings, medical guide wires
5-Axis Micro Machining
Tool diameter: 0.1 – 1.0 mm
5-axis micro machining combines simultaneous multi-axis movement with micro-scale tooling to produce complex micro geometries in a single setup. By eliminating re-fixturing between operations, 5-axis micro machining preserves positioning accuracy across intersecting features and undercuts. It is the process of choice for micro impellers, micro turbine blades, and complex medical implants requiring multi-directional micro features.
Typical Applications
Micro impellers, micro turbines, complex medical implants, micro housings, optical mounts
Micro Drilling
Tool diameter: 0.05 – 0.5 mm
Micro drilling produces holes as small as 0.05 mm (50 µm) in diameter using specialized micro drills and high-speed spindles. Depth-to-diameter ratios up to 10:1 are achievable with peck-drilling cycles and through-tool coolant delivery. Micro drilling is critical for fuel injector nozzles, medical catheter holes, printed circuit board vias, and micro-mold cooling channels.
Typical Applications
Fuel injector nozzles, catheter side holes, PCB vias, micro cooling channels, filter plates
Process Selection Guide
| Feature Type | Recommended Process | Achievable Precision | Relative Cost |
|---|---|---|---|
| Micro channels & cavities | Micro Milling | ±5 µm | Medium |
| Micro shafts & pins | Micro Turning | ±2 µm | Medium |
| Complex 3D micro geometry | 5-Axis Micro Machining | ±5 µm | High |
| Micro holes (≤ 0.1 mm) | Micro Drilling | ±3 µm | Low-Medium |
| Micro threads | Micro Turning | ±5 µm | Medium |
| Micro molds & dies | 5-Axis Micro Machining | ±2 µm | High |
| Flat optical surfaces | Micro Turning (Diamond) | ±1 µm | High |
| Micro slots & grooves | Micro Milling | ±5 µm | Low-Medium |
Process selection depends on feature geometry, material, tolerance, and volume. Many micro parts require multiple processes — for example, a micro valve body may use micro milling for the cavity and micro drilling for the flow holes. FIRMFG engineers recommend the optimal process combination based on your CAD model.
Minimum Feature Sizes
Understanding the limits of micro CNC machining is essential for designing manufacturable micro parts. Below is a comprehensive reference for minimum feature dimensions, categorized by feature type and limiting factor.
| Feature | Recommended Min | Absolute Min | Limiting Factor |
|---|---|---|---|
| Min Hole Diameter (Drilling) | 0.10 mm | 0.05 mm | Drill bit strength & flute chip evacuation |
| Min Hole Diameter (Milling) | 0.15 mm | 0.10 mm | End mill diameter & tool deflection |
| Min Slot Width | 0.15 mm | 0.10 mm | Tool diameter & chip clearance |
| Min Wall Thickness (Aluminum) | 0.08 mm | 0.05 mm | Material rigidity & vibration |
| Min Wall Thickness (Steel) | 0.15 mm | 0.10 mm | Cutting force & tool pressure |
| Min Internal Radius | 0.050 mm | 0.025 mm | Tool tip radius & wear |
| Max Depth-to-Diameter (Drilling) | 5:1 | 10:1 | Chip evacuation & drill alignment |
| Max Depth-to-Diameter (Milling) | 3:1 | 5:1 | Tool deflection & runout |
| Min Feature Size (General) | 0.10 mm | 0.05 mm | Tool availability & machine resolution |
Recommended vs. Absolute Minimums
Recommended minimums represent dimensions achievable with standard tooling and process parameters at normal cost. Absolute minimums push the boundary of manufacturability — they require specialized tooling, extended cycle times, and may have lower yield rates. Designing to recommended minimums balances precision with cost and reliability.
Material-Dependent Limits
Minimum feature sizes vary by material. Softer materials like aluminum and PEEK support thinner walls and smaller features because cutting forces are lower. Harder materials like steel and titanium require larger minimum features due to increased tool deflection and cutting forces. Always specify material when evaluating design feasibility.
Materials for Micro CNC Machining
Material selection profoundly impacts micro machining feasibility, precision, and cost. Below are the five most common micro machining materials with machinability ratings and recommended parameters.
Aluminum (6061, 7075)
Machinability: Excellent
Aluminum is the most micro-machinable metal due to low cutting forces and excellent thermal conductivity. 6061 is preferred for general micro parts; 7075 offers higher strength for micro structural components. Built-up edge (BUE) is the primary challenge — resolved with polished tools and minimum quantity lubrication (MQL).
Recommended Parameters
Spindle 60,000–100,000 RPM · Feed 0.5–2 µm/tooth · Coolant: flood or MQL
Typical Micro Part Applications
Micro heat sinks, microfluidic chips, electronic housings, prototype micro structures
Stainless Steel (303, 304, 316)
Machinability: Good
Stainless steel micro machining requires sharp carbide or diamond-coated tools and rigid workholding. 303 is the most machinable due to its sulfur content. 316 is preferred for medical and marine micro parts due to superior corrosion resistance. Work hardening during micro cutting demands consistent chip load control.
Recommended Parameters
Spindle 30,000–60,000 RPM · Feed 0.3–1 µm/tooth · Coolant: high-pressure flood
Typical Micro Part Applications
Medical bone screws, surgical instruments, micro valves, chemical-resistant micro parts
Titanium (Grade 5 / Ti-6Al-4V)
Machinability: Fair
Titanium Grade 5 is challenging in micro machining due to its low thermal conductivity and chemical reactivity with tool materials. Sharp, fresh tools and high-pressure coolant are essential. Despite difficulties, titanium is widely used for medical micro implants because of its biocompatibility and strength-to-weight ratio.
Recommended Parameters
Spindle 20,000–40,000 RPM · Feed 0.2–0.8 µm/tooth · Coolant: high-pressure through-tool
Typical Micro Part Applications
Medical implants, aerospace micro fasteners, micro optical mounts, dental components
PEEK
Machinability: Excellent
PEEK is the preferred engineering plastic for micro CNC machining. Its excellent machinability allows crisp micro features without burring. Medical-grade PEEK (ASTM F2026) is used for implantable micro components. Thermal expansion must be accounted for in tolerance stack-up — PEEK expands 4–5× more than metals per degree.
Recommended Parameters
Spindle 40,000–80,000 RPM · Feed 1–5 µm/tooth · Coolant: air blast or MQL
Typical Micro Part Applications
Medical implants, micro insulators, chemical-resistant micro housings, micro gears
Brass (C360, C260)
Machinability: Excellent
Free-machining brass (C360) offers the highest micro-machinability of any metal. Its chip-breaking characteristics produce clean micro features with minimal burr formation. Brass is ideal for micro electrical and electronic components requiring both conductivity and precision. Dry machining is often possible, simplifying process setup.
Recommended Parameters
Spindle 60,000–120,000 RPM · Feed 1–3 µm/tooth · Coolant: MQL or dry
Typical Micro Part Applications
Micro electrical contacts, micro connectors, watch components, micro valves
Tolerances and Accuracy
Micro CNC machining tolerances are measured in micrometers. Understanding tolerance grades, the factors that affect precision, and how accuracy is verified is essential for specifying micro parts correctly.
| Tolerance Grade | Tolerance | Typical Application | Equipment & Verification |
|---|---|---|---|
| General Micro | ±0.010 mm (±10 µm) | General micro components, non-critical features, prototypes | Standard micro CNC, optical comparator verification |
| Precision Micro | ±0.005 mm (±5 µm) | Functional micro parts, mating components, medical devices | Precision micro CNC, CMM verification |
| Ultra-Precision | ±0.002 mm (±2 µm) | Optical components, micro molds, aerospace micro parts | Ultra-precision micro CNC, interferometer verification |
Factors Affecting Precision
Thermal Expansion
Impact: A 1°C temperature change causes 2.3 µm expansion per 100 mm of aluminum. At micro scale, this exceeds the tolerance band.
Solution: Temperature-controlled environment (±0.5°C), in-process thermal compensation, adequate warm-up cycles.
Tool Deflection
Impact: A 0.1 mm end mill deflects significantly under even small cutting forces, causing dimensional errors and poor surface finish.
Solution: Minimize tool overhang, use ultra-rigid tool holders, optimize cutting parameters for minimum cutting force.
Vibration & Chatter
Impact: Micro tools are extremely sensitive to vibration. Chatter causes edge chipping, poor surface finish, and catastrophic tool failure.
Solution: Tuned spindle speeds, rigid workholding, vibration-damping tool holders, high-damping machine structure.
Tool Wear
Impact: At micro scale, even 5 µm of tool wear significantly changes feature dimensions. Micro tools wear faster due to high surface-speed-to-volume ratio.
Solution: Tool wear monitoring systems, frequent tool changes, diamond-coated or single-crystal diamond tools for hard materials.
Runout
Impact: Spindle runout of 2 µm on a 0.1 mm tool means 4% diameter error — enough to break the tool or oversize the feature.
Solution: Precision collets and shrink-fit holders with runout < 1 µm, regular spindle runout verification.
Verification Methods
Micro parts require specialized metrology. Conventional tactile CMM probes (2–3 mm ruby tip) are too large to access micro features. FIRMFG uses non-contact and high-magnification measurement systems to verify every critical dimension:
White Light Interferometer
Provides 3D surface topography maps with sub-nanometer vertical resolution. Measures surface roughness, step height, and micro-feature dimensions non-contact. Essential for verifying optical-grade surfaces and micro cavity depths.
Laser Measurement System
Laser-based dimensional measurement with 0.1 µm resolution. Verifies micro hole diameters, slot widths, and positional accuracy on features too small for tactile probing. Fast, non-contact, and suitable for inline inspection.
Scanning Electron Microscope (SEM)
SEM inspection provides 10,000× magnification for visual verification of micro features, edge quality, burr formation, and surface defects. Used for first article inspection of critical micro components and failure analysis.
Optical CMM
Non-contact coordinate measuring machine with video probing for micro features. Measures 2D and 3D geometry on parts too delicate or too small for conventional tactile CMM probes. Accuracy to ±1 µm.
Micro CNC Machining Applications
Micro CNC machining enables innovation across industries where miniaturization, precision, and reliability converge. Here are five sectors where micro machined components are mission-critical.
Medical Devices
Micro CNC machining is indispensable for medical device manufacturing, where part dimensions shrink while precision requirements intensify. Biocompatible materials like titanium, stainless steel, and PEEK are machined into implantable and surgical components with features invisible to the naked eye.
Specific Examples
Bone screws with micro threads, dental implants, surgical staple cartridges, micro catheter holes, cochlear implant components, micro surgical forceps
Aerospace
Aerospace micro machining produces fuel system components, sensor housings, and micro actuators where weight reduction drives miniaturization. Turbine engine cooling holes and micro fuel injector nozzles demand hole diameters under 0.1 mm with tight positional accuracy.
Specific Examples
Turbine blade cooling holes, fuel injector micro nozzles, micro pressure sensors, satellite micro actuators, gyroscope components
Electronics
The electronics industry relies on micro CNC machining for connectors, heat dissipation structures, and packaging components. As devices shrink, micro machined heat sinks, connector pins, and RF shield housings replace stamped and molded alternatives for prototype and low-volume production.
Specific Examples
Micro connectors, RF shield housings, micro heat sinks, semiconductor test sockets, micro antenna mounts
Optics
Micro optics manufacturing demands the highest precision in CNC machining. Micro lens molds, optical fiber connectors, and laser collimation housings require surface finishes measured in nanometers and feature positioning to single-digit micrometers.
Specific Examples
Micro lens injection molds, optical fiber ferrules, laser diode housings, micro prism mounts, diffractive optical element molds
Defense
Defense applications require micro machined components for guidance systems, fuzing mechanisms, and miniature sensors. These components must perform reliably in extreme environments, driving demand for micro machining in hardened steels, titanium, and exotic alloys.
Specific Examples
Fuse components, micro guidance gyroscope parts, sensor housings, micro actuators, initiator components
Key Challenges in Micro CNC Machining
Micro machining introduces challenges absent at conventional scale. Understanding these challenges — and their solutions — is essential for producing reliable micro parts and selecting a capable supplier.
| Challenge | Root Cause | Solution |
|---|---|---|
| Tool Breakage | Micro tools (0.1 mm diameter) have minimal bending strength. Inconsistent chip load, runout, or sudden force spikes snap the tool instantly. | Minimum chip load control via adaptive feed rate, runout verification before each run, vibration monitoring, and tool path optimization to maintain constant chip thickness. |
| Built-Up Edge (BUE) | Material adheres to the micro tool cutting edge, altering geometry and degrading surface finish. Prevalent in aluminum and stainless steel micro machining. | Optimize coolant supply (MQL or high-pressure flood), use polished or diamond-coated tools, increase cutting speed to elevate cutting temperature beyond the BUE formation zone. |
| Thermal Deformation | Cutting heat concentrates in the tiny tool and workpiece. At micro scale, even small thermal inputs cause dimensional drift exceeding the tolerance band. | Temperature-controlled machining environment (±0.5°C), low heat input parameters, through-tool coolant delivery, and in-process thermal compensation algorithms. |
| Tool Wear Monitoring | Micro tools wear rapidly due to high surface-speed-to-volume ratio. Wear of 5 µm on a 0.1 mm tool changes the effective diameter by 10%. | Online tool monitoring systems using acoustic emission or spindle power sensing, scheduled tool changes based on cutting time, and post-cut inspection of witness features. |
| Workholding Deformation | Conventional clamping forces deform micro parts. A 0.1 mm wall cannot withstand standard vise pressure without bending. | Micro specialized fixtures: vacuum chucking, wax potting, magnetic fixtures for ferrous materials, low-force mechanical clamps, and custom soft jaws conforming to part geometry. |
| Burrs & Edge Quality | Micro machining produces burrs that are difficult to remove. At micro scale, a 10 µm burr is 10% of a 0.1 mm feature size. | Optimize cutting parameters for minimal burr formation, use sharp fresh tools, employ cryogenic deburring or electropolishing for burr removal, and design parts to direct burrs to non-critical edges. |
Each of these challenges is manageable with the right equipment, process parameters, and experience. FIRMFG's micro machining team has developed optimized processes for every common material and feature type, ensuring consistent results even at the limits of micro manufacturability.
How to Choose a Micro CNC Machining Supplier
Not every CNC shop can machine micro parts. Use this evaluation checklist and RFQ guide to identify a partner with genuine micro machining capability.
Supplier Evaluation Checklist
- Spindle speed capability: verify the shop operates spindles at 40,000+ RPM for true micro machining. Standard CNC spindles (8,000–24,000 RPM) cannot achieve micro-scale finishes.
- Machine resolution: confirm positioning resolution of 1 µm or better. Ask for the machine specification sheet — control resolution directly determines the smallest achievable feature.
- Tool inventory: check availability of micro tools (0.1–1.0 mm) in carbide, diamond-coated, and single-crystal diamond. Micro tool sourcing is a common bottleneck.
- Inspection equipment: verify access to white light interferometry, optical CMM, or SEM. Tactile CMM probes are too large for micro feature verification.
- Temperature control: confirm the machining environment is temperature-controlled to ±1°C or better. Thermal drift is a leading cause of micro part rejection.
- Material experience: ask for examples of micro machined parts in your specific material. Micro machining behavior varies dramatically between aluminum, steel, titanium, and plastics.
- Quality system: verify ISO 9001:2015 certification and ask about inspection reporting. Micro parts require 100% inspection, not sampling.
- Engineering support: confirm the shop provides DFM feedback on micro features before machining. A knowledgeable partner will flag features at the limit of manufacturability.
RFQ Preparation Guide
To receive an accurate quote for micro CNC machined parts, provide the following information with your request:
Complete 3D CAD model (STEP or IGES) with all micro features fully defined — 2D drawings alone are insufficient for micro parts.
2D drawing with explicit tolerance callouts on all critical micro features. Specify ±µm values, not generic title block tolerances.
Material specification including alloy/grade and heat-treat condition (e.g., Ti-6Al-4V per ASTM F136 for medical).
Surface finish requirements per feature — specify Ra values in µm. Differentiate between functional and non-functional surfaces.
Inspection requirements: specify which features require 100% inspection and what measurement method is acceptable.
Quantity and delivery schedule: micro parts have significant setup cost. Indicate prototype vs. production volumes for accurate pricing.
Application context: sharing the part function helps the supplier recommend process, material, and tolerance optimizations.
Micro CNC Machining FAQ
Answers to the most common questions about micro CNC machining services at FIRMFG.
QWhat is micro CNC machining?
Micro CNC machining is a precision manufacturing process that uses miniature cutting tools — as small as 0.1 mm in diameter — on high-speed, high-resolution CNC machines to produce parts with feature sizes below 1 mm and tolerances to ±5 µm or tighter. It encompasses micro milling, micro turning, 5-axis micro machining, and micro drilling. Unlike conventional CNC machining, micro CNC machining requires specialized equipment with nanometer-class control resolution, spindles operating at 40,000–150,000 RPM, and ultra-rigid machine structures to minimize vibration and thermal drift at the micro scale.
QWhat is the minimum feature size you can machine?
FIRMFG achieves minimum feature sizes of 0.05 mm (50 µm) in micro drilling and 0.1 mm (100 µm) in micro milling. Minimum internal radii of 0.025 mm (25 µm) are possible with appropriately sized micro tools. Minimum wall thickness depends on material: 0.05 mm for aluminum, 0.1 mm for steel. Maximum depth-to-diameter ratios are 10:1 for micro drilling and 5:1 for micro milling. These limits are driven by tool strength, chip evacuation, and machine resolution. Features at the absolute minimum require specialized tooling and may increase cost and lead time.
QWhat tolerances can micro CNC machining achieve?
FIRMFG offers three tolerance grades for micro CNC machining: General Micro at ±0.010 mm (±10 µm) for non-critical features, Precision Micro at ±0.005 mm (±5 µm) for functional and mating components, and Ultra-Precision at ±0.002 mm (±2 µm) for optical and aerospace micro parts. Tolerances are verified using white light interferometry, laser measurement, optical CMM, and SEM inspection. Achieving ±2 µm requires temperature-controlled environments (±0.5°C), precision tool holders with runout below 1 µm, and diamond tooling for certain materials.
QWhat materials can be used for micro CNC machining?
Common micro CNC machining materials include aluminum (6061, 7075) for excellent machinability, stainless steel (303, 304, 316) for medical and corrosion-resistant applications, titanium (Grade 5 / Ti-6Al-4V) for implantable and aerospace components, PEEK for medical-grade plastic micro parts, and brass (C360) for electrical and electronic micro components. Other machinable materials include copper, tool steel, tungsten carbide, ceramics, and engineering plastics. Material choice affects minimum achievable feature size — softer materials like aluminum and PEEK allow finer features, while harder materials like titanium require larger minimum features due to increased cutting forces.
QHow much does micro CNC machining cost?
Micro CNC machining cost is driven by setup time, tool cost, machining time, and inspection requirements. Micro tools ($20–$200 each) are consumed faster than conventional tools. A single micro machined prototype typically costs $200–$800 depending on complexity, material, and tolerance. Ultra-precision parts with ±2 µm tolerances and 100% inspection can exceed $1,000 per part. Production volumes of 100+ units reduce per-part cost significantly through setup amortization. FIRMFG provides free quotes with DFM feedback — upload your CAD files for a detailed price and lead time estimate within 24 hours.
QWhat industries use micro CNC machined parts?
Micro CNC machining serves industries requiring miniature precision components. Medical device manufacturing uses it for bone screws, dental implants, surgical instruments, and catheter components. Aerospace relies on micro machining for turbine cooling holes, fuel injector nozzles, and micro sensors. Electronics manufacturing uses micro machined connectors, heat sinks, and RF housings. Optics requires micro lens molds, fiber ferrules, and laser housings with nanometer surface finishes. Defense applications include fuse components, guidance system parts, and micro actuators. Any industry producing parts with features below 1 mm benefits from micro CNC machining capabilities.
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Learn MoreStart Your Micro CNC Machining Project
Upload your CAD files and get a free micro CNC machining quote within 24 hours. Our engineers provide DFM feedback on micro features, recommend the optimal process and material, and deliver ISO 9001 certified quality with tolerances to ±2 µm. From single prototypes to production volumes, FIRMFG is your micro machining partner.