CNC Milling Service for Prototypes — Parts in 1–5 Days.

From first-concept brackets to pre-production assemblies — Baosheng CNC milling turns your STEP file into a finished prototype in 1–5 days. 3-axis to full 5-axis simultaneous, aluminum to titanium, 1 piece or 50. Free DFM analysis. Factory-direct pricing. Engineer quotes every file in 2 hours.

1-piece prototypes welcome
Free DFM analysis
ISO 9001 certified
Quote in 2 hours

// Machine specs

Max travel (3-axis)：2,000 × 1,500 × 800 mm

Spindle speed：Up to 18,000 RPM

Tightest tolerance：± 0.005 mm

Surface finish Ra：0.4 μm standard

Min end-mill dia.：Ø 0.3 mm (micro milling)

// Axes available

3-axis VMC：In-house · fastest route

4-axis indexing：In-house

5-axis simultaneous：In-house

Micro milling：In-house · Ø <0.5mm features

// Prototype lead time

Simple Al 3-axis：1–2 business days

Medium complexity：2–4 business days

5-axis complex：3–6 business days

With anodizing：+2 days

±0.005mm

Tightest milling tolerance

5-axis

Simultaneous in-house

1day

Fastest prototype lead time

60+

Surface finishes in-house

Certifications

ISO 9001:2015 ISO 13485 Medical IATF 16949 NDA & IP protected 20+ years experience Quote in 2 hours

CNC Milling vs Turning vs EDM — Which Process for Your Prototype?

Milling handles 80% of prototype geometries. Getting the process right before uploading saves 2 days. Here’s the decision guide — and when milling wins.

CNC Milling

Rotating tool · stationary workpiece

Flat faces, pockets, slots, counterbores
Complex 3D sculpted surfaces (5-axis)
Large prismatic parts up to 2,000mm
Multiple features in one setup (5-axis)
Housings, brackets, enclosures, plates
Cylindrical features — possible, not optimal
Long slender shafts — turning wins here

Best for: housings, brackets, enclosures, plates, complex structural parts — any prototype where the geometry is prismatic or freeform, not rotational.

CNC Turning

Rotating workpiece · stationary tool

Shafts, pins, bushings, connectors
External / internal threads (ID + OD)
Concentric bores — best roundness
High L/D ratio — long slender parts
Non-rotational prismatic geometry
Large flat features, pockets

Best for: shafts, connectors, nozzles, valve bodies, fittings — anything symmetric about an axis of rotation.

Wire EDM

Electrical discharge · no cutting force

Hardened tool steel (HRC 60+)
Ultra-tight slots — to ±0.002mm
2D profile cuts — dies, punches
No heat-affected zone or cutting force
3D surface features
Aluminum or plastics

Best for: hardened die inserts, precision 2D slots in hardened steel — when cutting force itself would deform the part.

Not sure which process fits your prototype? Upload your STEP — the engineer decides and explains in the free DFM report.

What CNC Milling Can Do for Your Prototype

Milling’s strength is geometry freedom — from a simple flat bracket to a 5-axis impeller. Here’s the range of prototype geometries we mill every day.

3-Axis milling

Prismatic Parts

Flat faces, parallel walls, pockets, slots, counterbores, through-holes, tapped holes. The fastest and cheapest milling route — most mechanical prototypes land here. Typical lead time: 1–2 days.

Fastest
Lowest cost
1-day available

3-Axis deep pocket

Housings & Enclosures

Electronic enclosures, optical housings, pneumatic manifold bodies. Depth-to-width ratio up to 4:1 with standard tooling. Beyond that, extended-reach tools or 5-axis approach paths. Minimum wall 0.8mm recommended.

Electronics
Optics
Pneumatics

5-Axis simultaneous

Freeform & Sculptured

Impellers, turbine wheels, orthopaedic implants, compound-angle brackets, lens mounts. One setup — the tool approaches from any angle. Eliminates repositioning errors that accumulate in multi-setup 3-axis work.

Aerospace
Medical
One setup

Thin-wall challenge

Thin-Wall Structures

Drone arms, lightweight brackets, UAV frames. Minimum wall: 0.8mm for 6061 aluminum, 0.5mm with specialist fixturing and reduced feed rates. Walls thinner than 0.8mm are flagged in the free DFM report with redesign suggestions and cost impact.

UAV / Drone
Lightweight
DFM critical

Milling Geometry Limits — Quick Reference

Feature	3-Axis milling	4-Axis indexing	5-Axis simultaneous	Our limit
Max part size	2,000 × 1,500 × 800mm	Ø400 × 600mm	600 × 500 × 400mm	By process
Min internal radius	R0.5mm (small end mill)	R0.5mm	R0.3mm	Tool-dependent
Max depth-to-width ratio	4:1 std · 8:1 extended tool	4:1	6:1 (angled approach)	Material-dependent
Min wall thickness	0.8mm Al · 1.0mm SS	0.8mm	0.5mm (special fixturing)	DFM review required
Surface finish Ra	0.4μm std · 0.1μm mirror	0.4μm	0.2μm on curved surfaces	By material
Tightest tolerance	±0.005mm std · ±0.002mm precise	±0.005mm	±0.002mm (1-setup benefit)	CMM verified
Undercut features	Not possible (standard tooling)	Limited	Full access via tool angle	5-axis recommended

From CAD File to Part — The Real Day-by-Day Timeline

Iteration speed is the whole point of CNC prototyping. Here is an honest day-by-day breakdown of what happens between your STEP upload and parts in your hands.

Day 1 — Morning

File uploaded · DFM review begins immediately

Upload your STEP. Engineer is assigned within 15 minutes. DFM analysis runs for 45–90 minutes depending on complexity. Written report and itemised quote arrive in your inbox by early afternoon.

STEP file uploaded

Day 1 — Afternoon

Quote approved · toolpath programming starts

You approve the quote. CAM programming begins immediately — for simple 3-axis parts this takes 30–60 minutes. Workholding designed, material pulled from stock, machine prepped.

Quote PDF approved

Day 1–2 — Machining

Parts running on the machine

Simple prototypes: first chips fly the same afternoon. Complex 5-axis parts: morning of Day 2. Critical dimensions verified with CMM during machining — not just at the end.

Day 2–3 — Finishing & QC

Deburring · surface finishing · inspection

As-machined: QC and packaging on Day 2. With Type II anodizing: add 2 days. With hard anodize: add 3–4 days. CMM report issued with every precision order.

Day 3–5 — Delivery

DHL/FedEx express dispatch · tracking provided

Export packaging protects precision surfaces. Tracking number sent at dispatch. Typical transit: USA 3–4 days, Europe 3–5 days, next-day within mainland China.

Tracking number sent

Lead Time Comparison — Baosheng vs Platform

Baosheng — factory-direct milling

Simple Al 6061 prototype：1–2 days

Medium complexity 3-axis：2–4 days

5-axis complex prototype：3–6 days

With Type II anodizing：+2 days

Design change re-quote：Same day, free

Rush (1-day) available：Yes

Platform route

Simple Al 6061 prototype：3–7 days

Medium complexity 3-axis：5–10 days

5-axis complex prototype：7–14 days

With Type II anodizing：+4–6 days

Design change re-quote：New order required

Rush available：Limited / premium

Why the difference?

Platform route: file → matching algorithm → 3rd-party shop accepts → they setup → they machine → platform QC → ship. Baosheng: file → our engineer → our machine → our QC → ship. Two fewer handoffs = two fewer days minimum.

Every Milling Process — In-House, From 1 Piece

Every process runs in our own facility. No subcontracting means faster lead times and one point of contact when something needs to change.

Fastest route · Lowest cost

3-Axis VMC Milling

The fastest and most economical route for prismatic aluminum prototypes. High-speed spindles at 18,000 RPM reduce cycle time and deliver Ra 0.8μm as-machined. Ideal for brackets, plates, enclosures, and fixtures. Most prototypes ship from this process.

Max travel：2,000×1,500×800mm
Spindle：18,000 RPM
Tolerance：±0.005mm standard
Lead time：From 1 day

5-axis · One setup

5-Axis Simultaneous

True simultaneous 5-axis for impellers, turbine blades, orthopaedic components, and freeform surfaces. One setup eliminates repositioning error and tolerance stacking. Your most complex prototype geometry — machined correctly, not worked around.

Axes：True 5-axis simultaneous
Tolerance：±0.002mm achievable
Undercuts：Full geometry access
Lead time：3–5 days prototype

4-axis · Circumferential features

4-Axis Indexing

Rotary axis adds circumferential features to cylindrical workpieces — radial holes, keyways, gear teeth, and cross-flats — without a separate turning operation. Best for parts that are “mostly cylindrical but with milled features” that don’t justify full 5-axis.

Rotation：360° indexing
Max dia.：Ø 300mm
Features：Radial holes, flats, slots
Lead time：2–4 days

Micro · Features <0.5mm

Micro Milling

End mills from Ø 0.3mm for fine details — sensor housings, microfluidic channels, connector pins, watch components. Climate-controlled measurement room compensates for thermal drift at this scale. Feature widths under 0.5mm routinely achieved.

Min tool dia.：Ø 0.3mm
Min feature：<0.5mm width
Tolerance：±0.003mm
Applications：Medical · sensors · optics

Prototype Surface Finishes — What to Specify and When

The right finish for a prototype is different from production. Specifying by function — not by aesthetics — keeps your lead time short and your budget controlled.

Best for most prototypes

As-Machined

Ra 0.8–1.6μm · included in base price

No cost premium — standard milling output
Shows toolpath marks — good for fit/function tests
Fastest lead time — no post-processing
Dimensional accuracy unchanged

Use when: testing fit, function, or assembly — not presenting to investors or end customers.

Most popular finish

Type II Anodize

5–25μm · +$3–8/pc · +2 days

Corrosion protection + colour (black, clear, blue, red)
Grows 2–12μm per side — adjust tight dimensions
Works best on 6061, 6063 — avoid 7075, 2024
Industry-standard for customer-facing Al prototypes

Use when: showing prototypes to customers, investors, or for photoshoot — the “Apple product” finish.

Wear-critical

Hard Anodize (Type III)

25–100μm · +$8–20/pc · +3–4 days

HV 400–600 — harder than mild steel
Dark gray/black — no colour option
+12–50μm per side — compensate dimensions
Wear tests, sliding surfaces, aerospace applications

Use when: prototype must test wear or sliding behaviour in service conditions. Spec: “Type III per MIL-A-8625”.

Texture + appearance

Bead Blast

Ra 0.8–3.2μm uniform · +$2–5/pc · +1 day

Hides toolpath marks — satin-matte uniform texture
Negligible dimensional change (<0.01mm)
Usually followed by Type II anodize for combined look
Works on all metals

Use when: consumer product prototype needs a finished look without anodize. Good pre-treatment before anodizing for uniform colour.

Corrosion / conductivity

Electroless Nickel

5–75μm uniform · +$8–18/pc · +2–3 days

Uniform coverage — including inside bores
HV 500–700 after heat treatment
Excellent solderability for connectors
RoHS compliant · aerospace / electronics

Use when: prototype requires solderability, electrical conductivity, or corrosion protection in areas inaccessible by line-of-sight plating.

Optical / precision

Mirror Polish

Ra ≤0.1μm · +$20–60/pc · +2–4 days

Manual polishing — diamond compound
Optical reflectors, mould cavities, implants
Only where functionally required — expensive
Specify surface, direction, and reference standard

Use when: optical function, articulating implant surface, or mould cavity demands Ra ≤0.1μm. Not for appearance — only for function.

If your prototype needs to…	Specify this finish	Cost add	Lead add
Test fit and function only	As-machined	$0	+0 days
Go in front of customers / investors	Bead blast + Type II anodize	+$5–13/pc	+3 days
Test corrosion resistance	Type II or III anodize	+$3–20/pc	+2–4 days
Prove wear / sliding behaviour	Hard anodize Type III	+$8–20/pc	+3–4 days
Solder to or conduct electricity	Electroless nickel or chem-film	+$4–18/pc	+2–3 days
Achieve optical / implant Ra <0.1μm	Mirror polish	+$20–60/pc	+2–4 days

What to Upload for Your Prototype Milling Quote

The file you send determines how fast we can quote and how accurately we can DFM your design. Here’s what works — in order of preference.

STEP

Recommended

ISO 10303 Standard for Exchange of Product Data

Universal solid geometry — all CAD systems export it. Preserves tolerance annotations if added. Fastest to quote — zero conversion needed. The only format we never have to ask you to re-export.

Quote under 2 hours

IGES

Accepted

Initial Graphics Exchange Specification

Surface model — older standard, still widely used. May require geometry healing before CAM toolpath generation. Prefer STEP if you have the option; if not, export as solid body from your CAD package.

May add 30 min for healing

.SLDPRT

Accepted

SolidWorks native part file

We open SolidWorks files directly. Retains full feature tree and parametric history — useful for DFM when the engineer needs to check design intent. Include version note.

Best for deep DFM

PDF / DWG

No 3D file?

Dimensioned 2D engineering drawing

No 3D model? Send a fully dimensioned 2D PDF or DWG — we model the geometry at no charge. Include all views, tolerances, thread callouts, and finish specs. Adds 1–2 hours to quote time.

+1–2hr quote time

What to Include Alongside Your File

Material specification

Grade, temper, and any cert requirement. e.g. “Al 6061-T6” or “SS 316L ASTM F138”

Required lead time

Tell us your deadline — we’ll quote standard and rush options side by side.

Surface finish spec

Function-based: “Type II anodize black” or “as-machined, deburr all edges”

Critical dimensions (optional)

Flag 2–3 features that matter most — helps the engineer prioritise DFM effort.

Ready to start?

Upload your file now. Engineer responds in 2 hours. Free DFM included. No obligation.

STEP · IGES · SLDPRT · PDF · DWG accepted

What Drives Your Prototype Milling Cost

Five variables explain 95% of prototype milling price differences. Understanding them lets you reduce cost before you even upload.

Prototype Milling Cost Drivers

Driver	Low-cost scenario	High-cost scenario
Quantity	50+ pieces — setup amortised	1 piece — 100% setup in 1 part
Axes required	3-axis prismatic geometry	5-axis simultaneous, compound angles
Material	Al 6061 — machines in seconds	Titanium — 4× slower cycle time
Tolerance	±0.05mm — standard 3-axis	±0.002mm — CMM + dedicated setup
Surface finish	As-machined Ra 0.8μm — free	Mirror polish Ra 0.1μm — manual labor
Setup count	Single setup — simple geometry	4+ setups — multiple datum references

DFM tip — most common overspend

Calling out ±0.002mm on every feature — even clearance holes and cosmetic pockets — is the single most common unnecessary cost driver. Each tight-tolerance feature adds CMM verification time. Our free DFM review identifies where tight tolerance is functionally needed vs. where ±0.05mm works identically. Average savings: 20–40% on inspection cost.

Indicative Prototype Pricing

Prototype / 1–5 pieces

From $12_{/ pc}

Al 6061 · 3-axis · as-machined · ±0.05mm · 1–3 day lead

Small batch / 10–50 pieces

Save ~40–55%_{vs 1-pc unit cost}

Setup amortised · batch scheduling · material savings

Complex 5-axis prototype

From $120_{/ pc}

Al 7075 · 5-axis · ±0.005mm · 3–5 day lead · CMM report

Production run (100–500 pcs)

Volume pricing_{+ Cpk ≥1.67}

SPC monitoring · dedicated tooling program · PPAP available

Free DFM Review — Every Quote

Our engineer reviews your milling design for wall thickness risks, pocket depth-to-width ratio, over-toleranced features, setup count reduction, and finish spec mismatches. Written report with cost savings quantified. Average DFM savings: 20–35% per prototype.

CNC Milling Prototype Supplier Comparison

Feature	Baosheng Industry ✓	Platform	Local job shop
Pricing model	Factory-direct, no markup	Platform + shop margin	Direct
5-axis in-house	Yes — no subcontracting	Network supplier	Often not available
Free DFM report	Written, every quote	Limited / algorithm	Verbal only
Design change re-quote	Free, same day	New order required	Varies
Quote turnaround	2 hours — real engineer	Instant — algorithm estimate	1–3 days
Lead time (simple Al)	1–2 days	3–7 days	5–10 days
CMM inspection report	Included on precision orders	Extra charge	Extra charge
Who reviews your design	Your assigned engineer	Algorithm / sales rep	Shop owner

From Titanium Drawing to Finished Part — 5 Steps

1.Upload Your File

STEP, IGES, or 2D PDF. Include material, quantity, tolerance, and finish requirements.

2.Free DFM Review

Engineer checks wall thickness, pocket depth, tolerance feasibility, and process selection. Written report in 2 hours.

3.Itemised Quote

Setup, cycle time, finishing, and inspection broken out separately. No hidden fees. Quote valid 30 days.

4.Mill & Inspect

Parts milled in-house. Critical dimensions CMM-verified. Non-conforming parts quarantined — never shipped.

5.Ship with Docs

CMM report + material cert enclosed. Express packaging protects precision surfaces. Tracking at dispatch.

CNC Milling Service for Prototypes — Questions Answered

How is CNC milling different from CNC turning for prototypes?

CNC milling uses a rotating multi-flute cutter against a stationary workpiece — ideal for prismatic, complex 3D, and freeform geometries. CNC turning rotates the workpiece against a stationary tool — ideal for cylindrical shafts, bores, and threads. Most prototype housings, brackets, and enclosures are milled. Most shafts, connectors, and nozzles are turned. If your part has both, our mill-turn centers handle it in one setup.

What is the minimum feature size for CNC milled prototypes?

With standard tooling: internal radius R0.5mm, slot width 1.0mm. With micro milling tools: internal radius R0.15mm, slot width 0.3mm. These are physical limits set by tool diameter and cutting force deflection — not machine capability. Our DFM review flags any feature that falls below safe limits for your material and geometry.

Can I get a 5-axis milled prototype in 1–2 days?

Simple 5-axis geometries: yes, in 2–3 days. Complex simultaneous 5-axis (impellers, freeform surfaces): typically 3–5 days. The constraint is toolpath programming time — a 5-axis impeller toolpath can take 3–4 hours to generate and verify. Rush 5-axis available on request — discuss your deadline when uploading.

What materials can be CNC milled for prototypes?

We mill aluminum (6061, 7075, 5052, 2024), stainless steel (304, 316L, 17-4 PH), titanium (Grade 5 Ti-6Al-4V, Grade 23 ELI), engineering plastics (PEEK, Delrin, Nylon, Polycarbonate), brass, copper, and exotic alloys (Inconel 718, Hastelloy). All materials available from 1 prototype piece — no minimum on any grade.

What files do I need for a prototype milling quote?

STEP is preferred — direct import, no conversion, fastest quote. We also accept IGES, SolidWorks (SLDPRT), CATIA, Pro-E, SAT, X_T, and 2D PDF/DWG. No 3D model? Send a dimensioned PDF — we model the geometry at no charge, adding 1–2 hours to quote time. Include material spec, surface finish, lead time requirement, and quantity.

Do you offer free design revisions between prototype iterations?

Yes — re-quoting is free and same-day. Submit your updated STEP referencing the previous quote number. We retain the setup strategy from your last revision — Rev 2 typically quotes faster than Rev 1 because workholding is already solved. No additional DFM charge for subsequent revisions.

What tolerance can CNC milling hold on a prototype?

±0.05mm general, ±0.010mm standard precision, ±0.002mm on specific features with dedicated setup and CMM verification. Aluminum holds tighter tolerances than steel or titanium due to lower cutting forces. Don’t specify ±0.002mm everywhere — our DFM identifies which features actually need it. Applying tight tolerance globally is the most common avoidable cost driver we see.

What does the free DFM analysis cover for milled prototypes?

Our DFM review checks: wall thickness below 0.8mm (vibration / deflection risk), pocket depth-to-width ratio above 4:1 (tool length limits), internal radii smaller than available end mills (impossible features), over-toleranced non-critical features (unnecessary cost), alloy-finish incompatibilities (7075 + Type II anodize = poor result), and setup count reduction opportunities. Written report, every quote, no charge.