Precision machining for critical parts and tooling.
CNC milling and turning, EDM, repair welding and bench fitting for components that allow no margin for error, with dimensional inspection backing every delivery.
In a mold, precision isn’t a finish: it’s the function.
Machining is the controlled removal of material until a defined geometry, tolerance and finish are reached. In toolmaking it is the heart of the work: cavities, cores, inserts, plates, slides and guides must fit together with clearances of hundredths of a millimeter so the mold closes, seals and ejects correctly for hundreds of thousands of cycles.
No single technology handles every geometry. CNC milling builds most of the shape; turning handles rotational parts; EDM reaches where a cutting tool can’t —sharp internal corners, deep thin ribs, already hardened steels—; and welding lets you repair and rebuild components instead of replacing them.
Integrating these technologies with casting, patternmaking and dimensional inspection under one roof lets us control the result end to end and respond quickly when production tooling needs maintenance.
Typical industry values. Achievable tolerance is validated per part based on geometry, material, size and process.
From drawing to machined part.
CNC machining
Cavities, inserts, plates and special parts for industrial applications.
02 / 05Industrial welding
Fabrication, repair and rebuilding of critical metal components.
03 / 05Assembly, fitting and finishing
Assembly, polishing, surface finishing and final preparation of the tooling.
04 / 053D scanning and inspection
Part digitization, reverse engineering and comparison against CAD.
05 / 05Custom parts and spare parts
Out-of-catalog spare parts from a sample, a scan or reverse engineering.
In-house machinery and machining ranges.
Maximum travel per machine to assess the dimensional capacity of each project: machining centers, CNC router, EDM, lathe, milling machines and hydraulic planers.
| Machine | X axis | Y axis | Z axis | Axes |
|---|---|---|---|---|
| Machining center · Type A | 1940mm | 1940mm | 700mm | 4 |
| Machining center · Type B | 2000mm | 800mm | 1000mm | 3 |
| Machining center · Type C | 1520mm | 760mm | 720mm | 3 |
| Machining center · Type D | 1020mm | 516mm | 516mm | 3 |
| CNC router | 3000mm | 1500mm | 650mm | 4 |
| Sinker EDM | 630mm | 350mm | 400mm | 3 |
| LatheX = swing (Ø) · Y = distance between centers | Ø 2000mm | 2000mm | 600mm | 2 |
| Milling machine · Type A | 850mm | 370mm | 680mm | 3 |
| Milling machine · Type B | 700mm | 300mm | 450mm | 3 |
| Hydraulic planer · Type A | 3000mm | 885mm | 250mm | 3 |
| Hydraulic planer · Type B | 1800mm | 900mm | 900mm | 3 |
Actual maximum dimensions depend on geometry, weight, workholding, tolerances, material, process and finish. Every project is validated with the Fundimoldes technical team.
Validate dimensional capacity for my project →Every geometry calls for its own technology.
Choosing the right process for each feature of the part is what separates a precise, cost-effective component from one that is expensive or impossible to make.
| Process | Principle | Best for | Keep in mind |
|---|---|---|---|
| CNC milling | A rotating tool removes material along toolpaths programmed in CAM. | Cavities and cores, plates, pockets, 3D surfaces and profiles. | The tool sets the minimum internal radius; pocket depth is limited by its length and rigidity. |
| CNC turning | The part rotates while a stationary tool shapes diameters, faces and threads. | Shafts, bushings, flanges, nozzles, pins and guides. | Ideal for rotational parts; concentricity between diameters is controlled in a single setup. |
| Sinker EDM | Electrical discharges between a graphite or copper electrode and the part, submerged in a dielectric fluid. | Deep ribs, sharp corners, blind cavities, textures and hardened steels. | Requires making the electrode; the finish depends on the discharge settings. |
| Repair welding | Arc-deposited filler metal (TIG, MIG or stick) to join, build up or rebuild. | Mold repair, build-up of edges and parting lines, structures. | Tool steels require preheating, compatible filler metal and stress relief. |
| Fitting and polishing | Manual bench work with stones, abrasive paper and diamond compounds. | Parting-line shut-offs, slide motion, cavity gloss. | The polish grade is specified according to mold finish standards and the polymer to be processed. |
The right steel defines the service life of the tooling.
Hardness, toughness, thermal conductivity, corrosion resistance and polishability compete with one another. These are the most widely used grades for molds and mechanical parts.
| Material | DIN equivalent | Typical hardness | Recommended use |
|---|---|---|---|
| P20 | 1.2311 · 1.2738 | ≈ 28–34 HRC prehardened | Medium- and high-volume injection molds, mold bases. Machined without hardening. |
| H13 | 1.2344 | ≈ 44–52 HRC hardened | Hot work: permanent molds, inserts under thermal shock, die-casting dies. |
| Type 420 stainless | 1.2083 | ≈ 48–52 HRC hardened | Corrosive polymers such as PVC, humid environments, mirror-polished cavities. |
| 4140 | 1.7225 | ≈ 28–32 HRC quenched and tempered | Shafts, machine parts and components with moderate wear. |
| 1045 | 1.1191 | Untreated or quenched and tempered | Plates, brackets, structures and general-purpose parts. |
| Aluminum 7075 · 6061 | EN AW-7075 · 6061 | ≈ 95–150 HB | Prototype, blow molding and thermoforming molds, fixtures. Fast machining and high thermal conductivity. |
| Copper alloys | Per specification | Variable | Inserts for hot zones of the mold and EDM electrodes. |
Treatments such as hardening, tempering or nitriding are defined by the application and included in the technical proposal when applicable.
From drawing review to measured delivery.
Precision is built at every stage; no stage can recover it if an earlier one lost it.
Technical review
Drawing, 3D model, tolerances, geometric tolerances and critical surfaces.
CAM strategy
Roughing, semi-finishing and finishing sequence; tool and parameter selection.
Workholding and datums
Definition of work zeros and clamping that prevent distortion and ensure repeatability.
CNC machining
Milling and turning of the main geometry with in-process checks.
EDM
Features the cutting tool can’t reach: sharp corners, deep ribs, blind cavities and textures.
Treatments
Hardening, tempering or surface treatments when the specification requires them.
Fitting and assembly
Polishing, fitting of shut-offs and moving parts, assembly of the complete unit.
Inspection
Dimensional inspection with calibrated instruments and 3D scan comparison against CAD.
Six rules that lower the cost of a machined part.
Machining cost is driven by machine time, the number of setups and special tooling. These design decisions affect all three.
Realistic internal radii
An end mill can’t leave sharp internal corners. An internal radius of at least one third of the pocket depth allows rigid, fast tools.
Reasonable depths
Pockets up to 3–4 times the tool diameter machine stably. Beyond that, you get chatter, long tools or EDM.
Tolerances where they matter
Every tenth of a millimeter of tighter tolerance adds time and inspection. Reserve tight tolerances for fits, seals and datums.
Clear datums
Defining datums and geometric tolerances avoids misinterpretation and ensures the part works at assembly, not just at inspection.
Fewer setups
Grouping features accessible from few faces reduces repositioning, the main source of accumulated error.
Threads and walls
A useful thread length of 1.5 times the diameter is usually enough. Very thin walls chatter and distort as stresses are released.
What determines a part’s real precision.
A machine’s tolerance is only the starting point. The final part accumulates the effect of several factors that are managed throughout the process.
| Factor | Effect on the part | How it’s managed |
|---|---|---|
| Temperature | A 500 mm steel part grows about 6 µm for every degree of difference. | Measurement at stabilized temperature and finishing passes after the part cools. |
| Internal stresses | As material is removed, the steel relaxes and can distort. | Prior roughing, resting or stress relief before finishing. |
| Tool wear | Progressive dimensional drift and poorer finish. | Tool life management and in-process verification. |
| Workholding | A part distorted by clamping measures right on the machine and wrong once released. | Proper fixtures and controlled clamping forces. |
| Multiple setups | Every repositioning adds error between features. | Sequence design with common datums and minimal setups. |
| Material | Hardness and homogeneity change cutting forces and finish. | Certified material and parameters tuned to each alloy. |
What we machine most often.
What we’re asked most about machining.
What tolerances can you hold?
It depends on size, material and geometry. General dimensions follow ISO 2768; functional fits are specified by IT grade or direct tolerance on the drawing and validated in the technical review.
Can you work hardened steels?
Yes. Pre-hardened steels are machined directly, and features in hardened material are produced with EDM, which does not depend on the hardness of the steel.
When is EDM used instead of milling?
When the geometry cannot be reached with a cutter: sharp inside corners, deep thin ribs, blind cavities or textures, or when the steel is already hardened. A graphite or copper electrode is made in the required shape and reproduced in the part through controlled electrical discharges.
Can you repair a damaged mold instead of making a new one?
In many cases, yes: it is built up with weld compatible with the steel, re-machined and fitted. It usually costs a fraction of new tooling and reduces downtime.
Do you make one-off parts?
Yes. Custom parts, spare parts and short runs are a regular part of our work, subject to technical and economic feasibility.
What files should I send?
Ideally a 3D model in STEP and a PDF drawing with tolerances, material, finishes and quantities. If you only have the physical part, we can capture it with 3D scanning.