Custom CNC Milling Services
CS Rapid MFG provides CNC milling services with competitive pricing. Equipped with advanced 3-, 4-, and 5-axis milling machines, we deliver consistent quality, tight tolerances, and fast turnaround for projects large or small.
Our CNC milling services allow you to create industrial-grade parts and components with automated speed and precision.
ISO 9001:2015 Certificated
50,000 Parts Made Monthly
100+ Materials with Metal and Plastic
20+ CNC Machines
Our CNC Milling Advantages
Support Low Volumes
For our CNC milling service, we produce prototypes, test parts, and low-volume production runs with the speed and accuracy needed for modern product development.
+/- 0.001″ Tolerances
Offers high-precision tolerances ranging from +/-0.001″ – 0.005″, depending on customer specs. We are the experts in making parts that are truly custom and ready to use.
3-Axis, 4-Axis, and 5-Axis Machining
From simple straight cuts to highly complex geometries, our 3-, 4-, and 5-axis CNC milling services are designed for rapid manufacturing. We manufacture everything from custom prototypes to final production components, with turnaround times as quick as 1 day.
20+ Materials Selection
We stock more than 20 plastic and metal materials suitable for various part applications across industries. Include ABS, CPVC, HDPE, Nylon, PMMA, PTFE, PVC, Aluminum, Brass, Copper, Stainless Steel, Titanium, etc.
ISO 9001:2015
CS Rapid MFG is an ISO 9001:2015 certified CNC machining service provider, offering high-precision custom machining services for prototypes, low-volume production, and full-scale manufacturing.
Custom CNC Milling Services by CS Rapid MFG
CNC milling is a high-precision, computer-controlled machining process that utilizes rotating cutting tools to remove material from a solid workpiece, enabling the engineering of complex geometries, intricate pockets, and exceptional surface finishes. This versatile manufacturing process enables the production of custom parts with tight tolerances, making it indispensable for demanding industries such as aerospace, automotive, medical devices, and consumer electronics.
Backed by our advanced in-house CNC machine shop, CS Rapid MFG delivers fast lead times, professional DFM feedback, and competitive pricing. From rapid prototyping to low-volume production, we help global businesses bring their precision-milled parts to life with uncompromised quality.
Design Guidelines for CNC Milling
Good CNC milling design improves machinability, lowers costs, and ensures quality. When milling, avoid deep pockets, thin walls, and sharp inside corners; use generous radii to reduce stress and tool wear. Chamfers enhance appearance and safety. Limit complex multi-axis curves to simplify fixturing. CS Rapid MFG’s basic guidelines for CNC milling include important design considerations to help improve part manufacturability, enhance cosmetic appearance, and reduce overall production time.
Part Size
Machined parts are limited in size by the machine envelope. 3-axis machines typically have a larger build size than multi-axis machines.
Fillets
Internal fillets should be as large as possible to allow the use of a large-diameter tool. The radius of the internal fillet should be greater than 1/3 the cavity depth to prevent tool damage.
Wall Thickness
Metal parts typically require a minimum wall thickness of 0.8 mm, while plastic parts require 1.5 mm. Thinner walls are vulnerable to vibration and deformation.
Cavity Depth
To minimize chatter, tool deflection, and other issues, the depth of machined cavities should be no more than 4 times their width.
Holes and Threads
Hole and thread diameters should correspond to standard drill bits and threading tools. Hole depth should generally be no more than 10x the diameter.
Feature Alignment
For 3-axis machining, adding features to multiple faces is more expensive. It can therefore help to design parts with holes and other features aligned on a single face.
Undercuts
T-slot undercuts can be around 3–40 mm wide. Dovetail undercuts work best at a standard angle of 45 or 60 degrees.
CAVITY DEPTH
To minimize chatter, tool deflection, and other issues, the depth of machined cavities should be no more than 4 times their width.
Flexible CNC Milling Solutions by CS Rapid MFG
From 3-axis and 4-axis to 5-axis machining, CS Rapid MFG produces prototypes, test parts, and low-volume production runs with accuracy and speed. Our CNC milling services maximize the flexibility to meet customers’ needs. Integrating both vertical and horizontal milling allows us to efficiently handle diverse geometries and part sizes, ensuring tight tolerances and rapid turnaround times.
3-Axis CNC Milling Services
4-Axis CNC Milling Services
CS Rapid MFG Precision CNC Milling
Prototype CNC Milling
Low-Volume CNC Milling
At CS Rapid MFG, we source and machine an extensive selection of engineering materials—including high-strength metal alloys, performance plastics, woods, and advanced composites—optimized for durability and cost-efficiency. Our engineering team provides expert DFM (Design for Manufacturability) analysis to streamline and optimize your part designs. Ready to start?
- ABS
- Acrylic
- Acetal (POM)
- Delrin 100 (AF)
- Delrin 150
- HDPE
- Nylon 6/6
- Polycarbonate
- PEEK / USP Cass VI TECAPEEK / PEEK GF30
- Polypropylene
- PVC
- UHMW PE
- ULTEM 1000
- ULTEM 2300
- Aluminum Alloy (2024, 6061, 6063, 7050, 7075-T6, MIC-6)
- Steel (Mild Steel & Hardened Steel)
- Brass (C360, C260)
- Titanium
- Copper (C110, C101)
- Stainless Steel (303, 304, 316, 17-4)
- Magnesium (AZ31)
- Wood
- Stone
- Glass
- Garolite
CNC Milling Surface Finishes
As part of our turnkey CNC machining capabilities, CS Rapid MFG provides expert surface finishing services that significantly enhance the durability, corrosion resistance, and cosmetic appearance of your milled parts.
As-Milled
The optimal choice for the fastest turnaround. At CS Rapid MFG, as-milled parts feature visible tool marks and undergo standard deburring to ensure all sharp edges are removed. Unless otherwise specified, we adhere to a standard surface roughness of 3.2 μm Ra (125 μin Ra) to meet your baseline precision needs.
Bead Blast
Our bead blasting process utilizes high-pressure, fine glass beads to thoroughly clean, deburr, and remove surface deposits without compromising part integrity. This treatment delivers a uniform, matte, or satin-like finish that effectively masks directional tool marks.
Anodized
CS Rapid MFG provides high-quality anodizing solutions for aluminum components. It is the industry choice for critical CNC applications across aerospace, electronics, medical devices, and heavy industrial equipment. Type II (Standard) creates an excellent corrosion-resistant layer and is available in various colors, including clear, black, red, and gold. Type III (Hardcoat) produces a thicker, exceptionally wear-resistant surface.
Chemical Finishes
These precision chemical treatments enhance surface properties without altering critical part dimensions. CS Rapid MFG offers chromate conversion (alodine), passivation, black oxide, and electropolishing to significantly improve corrosion resistance, surface purity, aesthetics, and specialized properties such as lubricity or electrical conductivity.
Platings
We provide advanced plating options—including electroless nickel, gold, silver, and zinc—to enhance conductivity, wear resistance, and corrosion protection. Our plating processes deliver durable, ultra-uniform coatings that safeguard part precision and surface quality.
Powder Coat & Paint
Powder coating and wet painting add a heavy-duty, protective barrier against corrosion, friction, and UV degradation. These options deliver a flawless, high-quality cosmetic appearance while safeguarding the underlying mechanical performance of your components.
Sanding & Polishing
By meticulously removing tool marks and refining rough surfaces, our hand-sanding and mechanical polishing deliver ultra-smooth, high-gloss finishes while preserving tight dimensional tolerances. This finish is perfect for customer-facing enclosures and high-end aesthetic prototypes.
E-Coating
Utilizing electrostatic deposition, our E-coating ensures complete, highly uniform coverage even across intricate, complex geometries. It serves as an exceptional primer or standalone finish for superior corrosion protection.
Put your parts into production today
Tolerances for CNC Milling by CS Rapid MFG
CS Rapid MFG provides expert CNC milling services with tolerance capabilities as tight as $\pm$0.01 mm to handle your critical, high-precision projects. Every part undergoes rigorous inspection against your 2D blueprints and GD&T specifications for consistent quality and assembly-ready fit. We easily adapt to industry standards, utilizing ISO 2768 for general tolerances and ASME Y14.5 for advanced geometric dimensioning whenever specified.
| 3-Axis CNC Milling (H3) | 4-Axis CNC Milling (H3) | 5-Axis CNC Milling (H3) | |
| Maximum Part Size | 4000 × 1500 × 600 mm | 1000 × 500 × 500 mm | 1000 × 500 × 500 mm |
| Standard Machining Tolerance | ±0.05 mm to ±0.10 mm | ±0.025 mm to ±0.05 mm | ±0.015 mm to ±0.03 mm |
| High Precision Tolerance | Down to ±0.025 mm | Down to ±0.01–0.02 mm | Down to ±0.01 mm achievable under optimal conditions |
| Hole-to-Hole Position Accuracy | ±0.03–0.08 mm | ±0.02–0.05 mm | ±0.01–0.03 mm |
| Perpendicularity (per 100 mm) | 0.04–0.10 mm | 0.02–0.05 mm | 0.01–0.03 mm |
| Flatness (per 200 mm) | 0.03–0.10 mm | 0.02–0.06 mm | 0.01–0.03 mm |
| Surface Roughness (Ra) | Ra 1.6–3.2 µm, down to Ra 0.8 µm | Ra 0.8–1.6 µm, down to Ra 0.4 µm | Ra 0.4–1.6 µm, down to Ra 0.2–0.4 µm (post-process required) |
| Thread Specifications | ISO metric / UNC / UNF threads, standard machining tolerance 6H / 6g | Precision threading per ISO standards | High-precision threading for functional assemblies |
| Lead Time (Simple Parts) | 1–3 days | 1–3 days | 2–5 days |
A Customer’s Words Mean More than Ours
FAQ's about CNC milling service
CNC milling operates by locking raw material onto the machine bed, where a high-velocity spindle rotates the cutting tool to shape the part. Precise dimensions are achieved through coordinated vertical and horizontal movements of the bed and spindle. In advanced production, multi-axis milling machines enable the tool to approach the workpiece from diverse vectors, allowing for the machining of complex geometries with fewer setup configurations.
Fast-track your production with CS Rapid MFG. Every RFQ receives a guaranteed response within 48 hours, paired with a free, comprehensive DFM review from our engineering team. We analyze your CAD drawings to catch potential manufacturing bottlenecks and propose cost-effective optimizations. By refining your designs for seamless CNC machining, we help you maximize part quality while aggressively driving down tooling costs and your final unit price.
From Rapid Prototyping to Production
CNC machining is an ideal manufacturing process whether you need a few parts or 10000+ units as end-used production parts. Contact us for professional CNC services at CS Rapid MFG.