Custom CNC milling service on five-axis equipment to ±0.005 mm, for flats, pockets, slots, profiles and the compound surfaces a three-axis machine cannot reach in one setup. Milling is the operation that turns a formed or welded part into something with a functional datum — the face another component bolts to, the pocket a bearing sits in, the bore a shaft runs in. ISO 9001:2015, registration 34025Q30296R0S. No minimum order quantity.

Carbide end mill cutting a rectangular pocket into an aluminium workpiece on a CNC machine table
An end mill cutting a pocket: the cut is established by the program and the tool path, not by a die.
±0.005 mmmachined tolerance
5-axisHDL-OKK DMU38
Flats, pockets, slots, profilesand compound surfaces
Post-weld millingdatums established on the finished structure
CMM + FAIdimensional reporting
ISO 9001:2015reg. 34025Q30296R0S

Why choose us for CNC milling

Five axes, fewer setups. A three-axis machine has to be repositioned to reach the far side of a part, and every repositioning adds its own error to the relationship between features. A five-axis machine presents the tool to the part from an angle, so features that must relate to each other can be cut without the workpiece moving — which is both more accurate and usually cheaper than adding an operation.

Milling is how we fix what the heat did. A welded frame or a drawn shell has moved by the time it reaches us. Milling the mating faces and bores afterwards establishes the datums on the finished geometry, which is more reliable than trying to prevent every movement earlier in the process. See metal welding.

We know what the material has been through. A bent or drawn workpiece is work-hardened and carries residual stress. Cutting it as though it were a fresh billet is a reliable way to produce a part that moves after machining. Because the forming operations are ours, that history is known rather than assumed.

We will tell you when not to mill. For a flat part with clearance holes, laser cutting and bending does the same job for less. Milling earns its cost when a dimension is functional — and we will say so on the quote rather than quietly pricing the expensive route.

What is CNC milling?

CNC milling removes material with a rotating multi-point cutter following a programmed path across a workpiece. Because the geometry lives in the program, the same machine produces a pocket, a slot or a sculpted surface without any change of tooling — and a design revision is an edit rather than a new die.

Common milling operations

Face milling — Produces a flat surface with a defined finish, usually as a datum face or a mating surface. Flatness and finish are set by the cutter and the feed, so a sealing face and a clearance face can be specified differently on the same part.

Pocket and slot milling — Cuts a recess or channel into the part. Corner radius is determined by the cutter diameter, which is why a pocket drawing should account for the tool that will make it rather than specifying a sharp internal corner.

Profile and contour milling — Follows a curved or complex outline to produce the part’s external shape, including three-dimensional contours that would need multiple setups on a three-axis machine.

Drilling, boring and tapping — Starting, finishing and threading holes. Where a hole must be round, straight and on a datum, boring after drilling is the operation that achieves it.

Five-axis simultaneous milling — The tool and the workpiece move together, allowing undercut features and compound angled surfaces to be machined in one continuous path. This is what removes the repositioning error from a complex part.

Post-weld facing and boring — Milling performed deliberately after assembly, to face a welded frame or bore a hole pattern on the finished structure rather than on a pre-weld position.

Key advantages of CNC milling

AdvantageWhat it means commercially
Functional tolerancesFaces, pockets and bores at ±0.005 mm, which forming cannot hold
Related features in one setupPosition error between features is held by the machine, not accumulated
No tooling costA design change is a program edit, so revisions stay cheap until the design freezes
Undercuts and compound anglesReachable in one operation on five axes
Finish controlFeed and speed set the surface, so a seal face is specified separately from a clearance face
One piece to productionThe same program runs the prototype and the batch

Common applications and scenarios for milled parts

Mating faces and sealing surfaces — Faces another component bolts or seals against, where flatness and finish decide whether the joint works. See industrial machinery.

Bearing seats, bushes and housings — Where a shaft or bearing has to run true. Boring is what makes the hole round and on position.

Pockets and recesses — Component mounting pockets, connector recesses and clearance cut-outs that forming cannot produce in the thickness required.

Threaded holes and ports — Threads and hydraulic ports, where the thread must be square to the mating face it is referenced to.

Prototypes and first articles — Where a part has to be right before tooling is committed. See rapid prototyping.

Machined features on formed parts — A stamped body with a milled face, a drawn housing with a machined neck, or a bent bracket with a machined seat. See stamping and deep drawing. Or see the parent capability, CNC machining.

When milling is the wrong answer — for a flat profile with clearance holes, laser cutting and bending is cheaper; for a predominantly round part, turning is the correct process; and for a hollow seamless form, drawing moves metal into shape rather than cutting it away.

How our CNC milling service works

1. Send the model or drawing. STEP or STP is ideal. Mark which dimensions are functional and which are reference — it changes the setup plan and the price. Engineering responds within 3 hours on working days.

2. Process and setup review, free. We confirm the tolerances are achievable, decide which faces should be machined in the same setup, and identify where a formed blank would be cheaper than milling from solid.

3. Material verification. Stock is checked against the mill certificate before machining.

4. Fixturing and machining. Five-axis work at ±0.005 mm. Thin walls and formed sections are supported rather than clamped hard, because deflection under clamping is one of the most common causes of an out-of-tolerance machined part.

5. Deburring and finishing. Edges are deburred as part of the operation; passivation, plating, anodising or coating follow as specified.

6. Inspection and shipment. CMM dimensional reports and first article inspection ship with the order.

CNC milling capabilities and specifications

ParameterCapability
Machining centreFive-axis, HDL-OKK DMU38
Tolerance±0.005 mm
Milling operationsFace, pocket, slot, profile, contour, five-axis simultaneous
Associated operationsDrilling, boring, tapping, threading
Post-process millingAfter welding, forming and galvanising
MaterialsCarbon steel, stainless steel (301/304/316L), aluminium (5052/6061), copper, brass
Surface finishesPassivation, zinc plating, anodising, powder coating, deburring
Minimum order quantityNone — from 1 piece
Engineering response≤3 hours on working days
Quality systemISO 9001:2015, registration 34025Q30296R0S
Plant15,000 m², 6 production lines, 85 employees

Materials we mill

Sheet metal sample plates in carbon steel, brushed stainless steel, aluminium and copper sheet
Materials we mill: carbon steel, stainless, aluminium and copper.

Aluminium — The most forgiving to mill and the usual choice for machined brackets, plates and housings. 6061 machines cleanly and takes threads well; 5052 is used where the part is also formed. Anodising follows where a defined, wear-resistant surface is needed. See the materials guide.

Carbon steel — Machines predictably with good finish control. Where the part has been formed first, residual stress can move it during machining, so roughing and finishing are separated where flatness matters.

Stainless steel 304 and 316L — Machines well with correct speeds and feeds. The grade work-hardens, so a light rubbing cut will harden the surface faster than it removes it — the classical way to blunt a tool on stainless. 316L is the usual choice where chlorides or hygiene govern.

Copper and brass — C260 machines freely and is used for terminals, contacts and fittings; C110 is softer and marks easily but is chosen where conductivity decides.

Quality control on milled parts

Milled parts are inspected against the dimensions marked functional, with related features cut in the same setup so their relationship is held by the machine. Where flatness or a surface finish is specified, it is measured and reported rather than assumed from the process.

Records available: CMM dimensional report, first article inspection, EN 10204 material certificate and surface finish measurements where an Ra value is specified. Third-party inspection by SGS, TÜV or BV can be arranged.

Frequently asked questions about CNC milling

What is the difference between three-axis and five-axis milling?

A three-axis machine moves the cutter in three straight directions, so reaching the far side or an angled face means repositioning the workpiece. Each repositioning adds its own error to the relationship between features. A five-axis machine tilts the tool or the table, so compound angles and undercuts are machined without moving the part — which holds related features together and usually removes an operation from the route.

Can you mill a face on a welded assembly?

Yes, and it is often the right answer. Welding puts heat into a structure and heat moves metal, so a face machined before welding can end up out of position. Milling the face and bores after welding establishes the datums on the finished geometry. Welding and five-axis machining are in the same plant, so the assembly does not travel between suppliers to get there.

Why does my pocket have rounded corners when the drawing shows sharp ones?

Because the pocket is cut by a rotating cutter, so the internal corner takes the radius of the tool. A drawn sharp internal corner cannot be produced by milling — it requires either a relief or an accepted corner radius. This is normally resolved at DFM review: we tell you the radius the cutter will leave so the mating part can be designed to suit.

Should I start from solid stock or a formed blank?

It depends which features are functional. If most of the part is a flat profile and only a seat or a bore needs precision, forming the blank and machining only that feature is normally much cheaper than milling the whole part from solid. If the geometry is mostly three-dimensional, starting from solid is faster. Send the drawing and we will price the realistic route.

What tolerance can you hold on milled features?

±0.005 mm is our normal working tolerance on five-axis equipment. What is achievable on a specific dimension depends on the feature, the material and how the part is held — a thin wall deflects under clamping, and a deep pocket is affected by tool reach. Mark the critical dimensions on the drawing and we will confirm before quoting.

Get a CNC milling quote

Send the 3D model or a 2D drawing with the functional dimensions marked, the material and the quantity. You will get a process review, a price, and where relevant a recommendation to form the blank and mill only the critical features. Normally within one working day. See how we price metal fabrication, or use the RFQ form.

Related capabilities

Related solutions and resources

Milling handles the prismatic work. These pages cover the alternative routes:

Read an Indian buyer’s verdict on machined parts made to drawing: India case study.

Standards referenced

1V1 engineering support, competitive pricing, on-time deliveries and high quality control. Please feel free to contact with us to get quotation.