A CNC machining quote is not a price list. It is the sum of a few concrete inputs: the material you specify, the machine time the geometry needs, the setup and programming work the part requires, the tolerance and surface finish the drawing calls for, and the quantity you order. Change any one of them and the price moves — which is why two suppliers can quote the same drawing differently, and why the fastest way to a lower price is usually a small change to the drawing rather than a different supplier.
This page explains how we build a price at CNC Machining Hub: which inputs we read from your files, which ones you control before sending the RFQ, and where designers most often pay for precision they do not need. Send a drawing with material, quantity and finish and you get a written quotation with the assumptions stated, so you can compare it with other quotes on equal terms.
Capabilities
- Cost review per drawing: we read geometry, tolerances, material and finish before quoting, and say which features are driving the price.
- Manufacturability feedback (DFM): we flag features that force extra setups, special tooling or hand finishing — and suggest cheaper equivalents where the function allows.
- Volume pricing: unit cost falls as setup and programming are amortised, so we quote the same part at several quantities when you ask.
- Material guidance: we quote common grades from stock (6061, 7075, 304/316, brass, copper, titanium, engineering plastics) and flag when a grade choice is inflating cost or lead time.
- Tolerance advice: standard machining holds ±0.1 mm; only the dimensions that need tighter tolerances should be toleranced tighter, and we say so before quoting.
- Finishing options: anodizing, plating, powder coating, polishing and passivation are quoted as separate line items so you can see what each step adds.
Typical materials
Material is usually the largest single variable. We machine aluminium alloys (6061, 7075, 5052), stainless steels (304, 316, 201), carbon and alloy steels, brass, copper, titanium and engineering plastics (ABS, PC, POM, PA6, PMMA, PEEK). Stock availability, machinability and certification requirements all affect both price and lead time, so tell us the application and we will tell you where a different grade costs less.
| Material / grade | Typical condition | Machinability | Where it fits |
|---|---|---|---|
| Aluminium 6061 | T6 (solution treated and aged) | Easy: free-cutting, good chip control | Brackets, housings, fixtures, prototypes into production |
| Aluminium 7075 | T6 / T651 | Harder: more tool wear, needs rigid setups | High-strength, weight-critical parts; not for welding |
| Stainless 304 / 304L | Annealed | Work-hardens: slower speeds, positive feed | General corrosion resistance, food and process equipment |
| Stainless 316 / 316L | Annealed | Tougher than 304: more tool wear | Chloride, marine, medical and pharmaceutical exposure |
| Carbon steel 1018 / 1045 | As-rolled / normalised | Easy to moderate; needs protection against rust | Shafts, plates, weldments, tooling bodies |
| Brass C360 | H02 half hard | Excellent: high speeds, clean finish | Fittings, bushings, connectors, decorative parts |
| Copper C110 | Annealed / H02 | Gummy: sharp tools and high rake angles | Conductivity, busbars, thermal management |
| Titanium Grade 5 (Ti-6Al-4V) | Mill annealed | Difficult: low speeds, heat control, tool wear | Aerospace, medical and lightweight high-strength parts |
| Engineering plastics (POM, PEEK, PA) | Extruded / annealed | Easy to gummy: soft jaws, sharp tooling | Insulation, low friction, chemical and wear parts |
Finishes
Finishing is quoted per operation: as-machined, anodizing, plating, powder coating, polishing, passivation, bead blasting or a drawing-specified finish. Cosmetic requirements are the usual hidden cost — a decorative surface across a whole part costs far more than a defined functional finish on the faces that need it.
| Finish | What it does | Specify it when |
|---|---|---|
| As machined | Tool marks left visible; Ra typically 1.6-3.2 µm | The part only has to function |
| Bead blast | Uniform matte surface, hides tool marks | Cosmetic parts before anodising |
| Anodising Type II | Builds an oxide layer; colour options | Aluminium appearance plus mild corrosion and wear resistance |
| Hard anodising Type III | Thicker, harder oxide layer | Sliding or wearing aluminium surfaces |
| Chromate conversion | Thin protective film that stays conductive | Electrical bonding or grounding on aluminium |
| Electroless nickel | Uniform, hard, corrosion-resistant layer | Wear plus corrosion, including inside bores |
| Zinc plating | Economical sacrificial corrosion protection | Steel parts in indoor or sheltered service |
| Powder coat | Thick, durable, decorative layer | Appearance is the requirement |
| Passivation | Removes free iron and restores the oxide film | Stainless parts after machining |
| Stress relief / heat treatment | Relieves residual stress before or after cutting | Thin walls and tight tolerances that must survive machining |
Tolerances
Standard CNC tolerances are typically ±0.1–0.2 mm, with precision work to ±0.05 mm or tighter on the features that require it. Tolerance is a cost multiplier: every dimension held tighter than the function needs adds inspection time, slower cutting and a higher scrap risk, so we review the drawing and confirm what is achievable before quoting.
| Callout | What it needs | Effect on cost and lead time |
|---|---|---|
| General: ±0.25 mm / ±0.010 in | Standard tooling, dimensional check | Baseline: no adder |
| Standard: ±0.13 mm / ±0.005 in | Machine in good condition, first-article check | Small adder; the usual quoting default |
| Tight: ±0.025 mm / ±0.001 in | Ground or diamond tooling, temperature control, CMM | Step change: slower cuts plus full inspection |
| Precision: ±0.013 mm / ±0.0005 in | Finish passes, gauging, controlled environment | Machining dominates the price; often a separate operation |
| Position / angularity (GD&T) | Datum control, one setup where features are related | Depends on how many setups the datum spans |
| Surface finish Ra 0.8 µm or finer | Finer stepovers, polishing or a finishing pass | Adds a process step, not just machining time |
Key Specifications
| Specification | Value |
|---|---|
| tolerance | ISO 2768 (Class M) |
| tolerance | 0.0001 in |
| tolerance | ±0.001" |
Process Options
- CNC machining is a subtractive manufacturing process.
- Finishing Options: Black Oxide, Electropolishing, ENP, Media Blasting, Nickel Plating, Passivation, Powder Coating, Tumble Polishing, Zinc Plating, Vibratory Tumbling
- EPX 82 is processed using Carbon DLS
- MUD is a type of mold that uses a standard injection molding frame.
- Different taper turning methods suit different jobs. Compound slides often handle short tapers, while CNC interpolation and taper attachments improve repeatability on longer parts
- G92 is used by programming one or more G92's right after the G76 threading cycle
- Estimates are provided through an auto-quoted method.
- EDM relies on a voltage and a thin wire
- Advanced machining processes like micro-machining and EDM are used to create small, precise mold cavities and cores
Surface Finish Reference
- The finish of MoldTech MT11010 is a fine matte texture.
- The finish of MoldTech MT11020 is a medium matte texture.
- The finish of MoldTech MT11030 is a coarse matte texture.
- SPI A-1 has a surface roughness of 0.012–0.025 µm.
- SPI B-2 has a finish of Medium semi-gloss.
- SPI B-2 has a surface roughness of 0.10–0.15 µm.
- SPI C-3 has a surface roughness of 0.63–0.70 µm.
- Super high gloss, polished with a Grade #3 (6000-grit) diamond buff to Ra 0.012–0.025 µm.
- Medium semi-gloss, finished with 400-grit paper to Ra 0.10–0.15 µm.
- Normal matte, polished with 320-grit stone to Ra 0.63–0.70 µm.
Tolerance Reference
- The tolerance with drawing for CNC Milling is as low as +/- 0.005 mm.
- FDM 3D printing offers a low-cost component with average accuracy and uses thermoplastics for 3D printing.
- Wire Cut EDM is highly accurate.
- The U6 H.E.A.T machine achieves tight tolerances.
- Die sinker EDM is capable of maintaining tight tolerances
- The shop needs to have CNC machines that can achieve a specific tolerance.
Industries We Serve
- antennas
- automotive
- CNC machined parts
- custom parts
- electronics
- medical diagnostic
- optical displays
- optical_systems
Material Reference
- ABS
- Austenitic Stainless Steel
- Carbon steel
- ceramic
- composites
- Copper - T2
- copper or graphite
- Hardened Materials
- High Impact Polystyrene
- Low-density polyethylene
- MDF
- metal
- Polybutylene Terephthalate
- SUS304
- thermoplastics
- thick metal sheets
- tungsten carbide
Related Processes
Injection Molding
used for
Laser Marking
used for
mass_production
used for
Common Applications
- plastic molded parts
- Aerospace
- Robotics
- consumer goods
- energy
Ordering, Lead Times & MOQ
Custom CNC parts carry no forced MOQ; ordering from a single prototype piece is standard industry practice.
Instant-quote platforms publicly advertise prototype lead times of 1-3 business days.
Online RFQ is the industry-standard flow: upload a 3D model (STEP/STP/DWG/DXF), receive an instant quote or engineer review, then production, inspection, and delivery.
Frequently asked questions
What information do you need to quote a CNC part accurately?
A 3D model (STEP or STP preferred), a 2D drawing with tolerances, material and finish, the quantity you need, and any inspection or documentation requirements. If a dimension is critical, mark it on the drawing — that is the single biggest factor in whether two quotes are comparable. Incomplete files produce quotes with assumptions, and assumptions are where prices move later.
Is there a minimum order quantity, and how does volume affect price?
There is no minimum order quantity: you can order a single prototype part. Because setup and programming are one-time costs, unit price normally falls as quantity rises, then flattens once the run is long enough to absorb them. If your first order is small, say so — we will quote the prototype and the production quantity together so you can see the difference before committing.
What is the lead time, and what does expedition cost?
Standard production lead time is 15–25 days from order, depending on material availability, finishing and inspection requirements. Expedited schedules are quoted per project, and the cost depends on whether the work is queue-time or material-time — we will tell you which one is your constraint. Lead time and price are confirmed in the quotation, not here.
What tolerance should I specify?
Specify tight tolerances only on critical features. Standard ±0.1 mm covers most features. Tighter tolerance = cost multiplier; apply selectively via drawing GD&T.
How is quality controlled?
First-article inspection in our own shop before the first production order. In-process checks. Final inspection report (dimensions) with shipment. Material certs (mill test reports) on request.
Is my design protected?
NDA before file exchange. Files used only for your production. No resale of custom designs.
Which material should I choose?
Function first: strength, weight, corrosion, cost. Common pairings: 6061 general, 304/316 corrosive env., PEEK medical. See materials guide pages.
Which surface finish do I need?
Anodizing for aluminum corrosion/wear/color. Passivation for stainless. Plating for conductivity/steel protection. Cosmetic vs functional distinction.
How do you ship and what terms?
DHL/FedEx/UPS express for samples and small batches. Air/sea freight for production volumes. Incoterms: EXW/FOB/DAP/DDP options.
Sources · 4
- rapiddirect.comIndustry peer technical page
- jlccnc.comIndustry peer technical page
- fictiv.comIndustry peer technical page
- norck.comIndustry peer technical page
Technical references cited for verifiability — not supplier recommendations. Browse the research library.
Related Knowledge
Capability commitments on this page are owner-confirmed (2026-09-21).