Services
CNC Machining
3-, 4- and 5-axis milling, turning and mill-turn for tight-tolerance metal and engineering plastic parts — from a single prototype to low-volume production.
CNC machining removes material from solid stock, so it carries no tooling constraint: one part is viable, and a dimensional revision is a programme change rather than a tool change. When a part needs tight tolerances, metal properties, or geometry too involved to form in a single operation, machining is usually the most direct route.
We apply it to two situations. The first is development work — functional prototypes and fit checks, where speed matters. The second is pre-production supply, where repeatability matters. The equipment is the same; what differs is process control. For supply work the fixturing is fixed, tool parameters are locked, and in-process checks run through the batch.
Capabilities
- Equipment
- 3-axis, 4-axis, 3+2 and full 5-axis machining centres; CNC lathes; mill-turn
- Typical lead time
- 3–5 working days for simple parts; 7–12 for complex parts or parts with finishing (confirmed at review)
- Quantity
- From 1 piece; typical batches 1–500; larger volumes assessed per project
- Maximum part size
- Per machine travel — see equipment list (to be confirmed)
- Supporting processes
- Wire EDM, sinker EDM, deburring, stress relief and heat treatment (partnered)
Solutions
Functional prototypes and fit checks
Parts in production-grade material that can be assembled and tested, exposing real fit and strength problems before tooling is committed.
Precision and tight-tolerance parts
Bearing seats, sealing faces and guide surfaces held through unified datums and operation consolidation, which keeps stack-up under control.
Complex surfaces and multi-face work
Five-axis work completes multiple faces in one setup, removing the positional error that repeated re-fixturing introduces — and shortening lead time.
Low-volume on-demand supply
For volumes where tooling does not pay back, machined parts ship directly, and design revisions cost no tooling rework.
Process Overview
A rotating cutter and a programmed toolpath remove stock progressively. Four things decide the result: fixture rigidity, toolpath, cutting parameters, and choice of datum.
Every re-fixturing introduces fresh error, so process planning is largely about minimising setups and getting the critical mating dimensions cut in the same setup. That is where five-axis equipment earns its cost on precision work.
Materials
- Aluminium: 6061-T6, 6082, 7075-T6, 5052, 2024
- Stainless steel: 303, 304, 316L, 17-4PH
- Carbon and alloy steel: 1045, A36-equivalent, 40Cr
- Copper and brass: C11000, oxygen-free C10100, H62 brass
- Titanium: Ti-6Al-4V (Grade 5), commercially pure
- Engineering plastics: ABS, PC, POM, PA6/PA66, PMMA, PEEK, PPS, UHMW-PE
Surface Finishes
- Bead blasting (80#–240#)
- Anodising (clear, black, colour, hard)
- Chemical conversion coating (chromate)
- Plating (nickel, chrome, zinc)
- Black oxide and phosphating
- Painting with matt or gloss clear coat
- Brushing and polishing
- Silk screen printing and laser marking
Tolerances & Size Limits
- Linear (general)
- From ±0.05 mm, to ISO 2768-m
- Linear (precision)
- ±0.02 mm, where called out on the drawing and confirmed at review
- Bores
- H7 commonly achievable; tighter grades require review of fixturing and gauging
- Surface roughness
- As-machined Ra 1.6–3.2 μm; finish-machined Ra 0.8 μm; polished by agreement
- Geometric tolerances
- Parallelism, perpendicularity and true position reviewed against the drawing — no blanket commitment
Design Guide (DFM)
Internal corner radii
Internal corners must carry a radius — cutters are round. Aim for R ≥ 1/8 of pocket depth, and keep radii consistent to reduce tool changes.
Wall thickness
At least 0.8 mm in metal, 1.5 mm in plastic. Thin walls deflect under cutting load, which costs you both tolerance and surface finish.
Deep pockets and holes
Keep pocket depth within about 4× cutter diameter. Beyond that, extended tooling loses rigidity and adds cost. Prefer standard drill diameters for deep holes.
Threads
Use standard metric threads at conventional depths (≤3× diameter). Leave relief at the bottom of blind tapped holes.
Tolerance callouts
Tighten only what genuinely needs it. Blanket ±0.01 multiplies machining and inspection cost while rarely improving assembly.
Datums and fixturing
Call out datums A/B/C on the drawing and leave at least one clampable face. On cosmetic parts, mark which faces must not carry fixture marks.
Text and marking
Engraved text needs ≥0.3 mm stroke width and ≥0.2 mm depth. For small type, laser marking beats milling.
Quality Control
- Drawing review: datums, critical dimensions and tolerance attainability
- Full first-article inspection before the batch is released
- In-process sampling of critical dimensions with tool wear tracking
- Re-check of affected mating dimensions after surface finishing
- Final inspection with dimensional report, CMM report or material certificate as agreed
FAQ
What do you need in order to quote?
At minimum a 3D file (STEP/STP preferred), quantity, material and required lead time. If there are critical tolerances, finishing or inspection requirements, send the 2D drawing as well — a dimensioned drawing speeds up quoting noticeably and avoids disputes later.
Can you quote from an STL file?
STL is a triangulated mesh with no exact surfaces or dimensions, so a CNC quote from it carries error. It is fine for a first estimate, but we recommend a STEP or native CAD file before ordering.
What is the minimum order quantity?
One piece. The unit price difference between one-off and batch work comes mainly from amortising programming, fixturing and first-article setup.
How tight a tolerance can you hold?
±0.05 mm on general dimensions, ±0.02 mm on precision features, H7 on bores as a common case. Anything tighter depends on the part geometry, material and gauging plan — we do not commit to a tolerance grade on a drawing we have not reviewed.
How are our drawings protected?
Uploaded files go to private storage with no public URL. Access in the back office is granted per project, downloads are logged, files are purged on the agreed retention schedule, and an NDA can be signed before anything is sent. See our File Upload & Confidentiality Statement.
Need cnc machining? Send the drawing to an engineer.
First reply within 30 minutes during working hours (4 working hours at the latest); full quote and DFM feedback typically within 12 working hours.