Technologies
When you're sourcing CNC machining tolerances in Egypt, the gap between what you need on paper and what a local shop can actually hold is where projects fall apart. This guide breaks down the toleranc
When you're sourcing CNC machining tolerances in Egypt, the gap between what you need on paper and what a local shop can actually hold is where projects fall apart. This guide breaks down the tolerance capabilities available from Egyptian CNC manufacturers, how to specify tolerances in your technica
When you're sourcing CNC machining tolerances in Egypt, the gap between what you need on paper and what a local shop can actually hold is where projects fall apart. This guide breaks down the tolerance capabilities available from Egyptian CNC manufacturers, how to specify tolerances in your technical drawings, and how to avoid the most common mistakes that inflate cost or kill your timeline.
A tolerance defines the acceptable range of variation for a dimension. If a shaft must be 25 mm in diameter with a tolerance of ±0.05 mm, any shaft between 24.95 mm and 25.05 mm is acceptable.
The tighter the tolerance, the more time and tooling precision the operation requires — and the higher the cost. Most engineers over-specify tolerances without realizing it, which means paying for precision that the application doesn't actually need.
| Tolerance Class | Range | Typical Application |
|---|---|---|
| Standard | ±0.1 – ±0.5 mm | General structural parts |
| Medium | ±0.025 – ±0.1 mm | Functional mechanical assemblies |
| Tight | ±0.005 – ±0.025 mm | Precision fits, bearings, gears |
| Ultra-tight | < ±0.005 mm | Aerospace, medical, optical |
Standard CNC machining centers in Egypt — including 3-axis and 4-axis VMCs and lathes — routinely hold tolerances in the ±0.025 mm range. Reputable shops running well-maintained equipment and using CMM inspection can hold ±0.005 mm on non-interrupted cuts.
Egypt's manufacturing base has grown significantly over the past decade. Industrial zones in 10th of Ramadan City, Borg El Arab, and the Suez Canal corridor host serious machining facilities with modern CNC equipment.
CNC turning (lathe work) on standard materials like mild steel, aluminum, and stainless steel:
For shafts going into bearings or close-clearance fits (H7/g6, H7/f7), specify the ISO tolerance class directly on your drawing. Competent shops will know how to interpret it.
CNC milling on 3-axis machining centers:
4-axis and 5-axis work can achieve better positioning repeatability but requires more specialized equipment — confirm availability before designing compound features.
EDM wire cutting is available in Egypt and is the right process when:
Wire EDM tolerances: ±0.005 – ±0.01 mm on profile. Surface finish depends on the number of skim cuts. Expect Ra 0.8 – 1.6 µm after finish passes.
Vague or missing tolerance callouts are the single biggest cause of rework in Egypt's machining supply chain. Here's what to do:
Instead of writing "±0.02 mm" on a shaft, use ISO fits: - H7/g6 = standard clearance fit - H7/k6 = transition fit - H7/p6 = interference press fit
Egyptian CNC machinists familiar with industrial work will recognize and correctly apply ISO fits. Shops working primarily on simple fabrication may not — confirm this when sourcing.
Apply tight tolerances only to functional features: bearing seats, pilot diameters, mating faces. Apply general tolerances (per ISO 2768-m or f) to non-critical dimensions. Put the general tolerance class in the title block.
If concentricity, perpendicularity, or true position matters for your assembly, use GD&T callouts. A drawing that says "straight" doesn't protect you — "cylindricity 0.01 mm" does.
Surface finish affects friction, sealing, and fatigue life. Use Ra values: Ra 3.2 is as-machined, Ra 1.6 is fine machined, Ra 0.8 is required before most plating operations.
Material affects what tolerances are achievable:
If your tolerance spec is at the edge of standard capability (±0.01 mm), material selection can be the difference between reliable production and repeated rework.
Over-tolerancing: Putting ±0.01 mm on a bracket bolt hole when ±0.2 mm would work fine. This raises cost and creates rejection headaches.
Under-tolerancing critical fits: Forgetting to specify bearing seat diameter tolerances, then finding assembled bearings have play or are impossible to press in.
Missing datums: GD&T callouts without properly defined datums are unenforceable. Make sure your datum reference frame is clear and physically measurable on the part.
Ignoring post-processing dimensional change: Heat treatment causes distortion. Anodizing adds 5–25 µm. Electroless nickel plating adds 5–12 µm per side. If you're plating, machine to undersize before plating.
Not stating measurement method: For tight tolerances, specify whether you need CMM verification or go/no-go gauging. This matters when ordering inspection reports.
When you submit a quote request at Entag, you need to provide:
The more specific your drawing, the more accurate the quote — and the lower the risk of cost surprises after first article inspection.
Entag's CNC machining service covers turning, milling, EDM wire, EDM spark, and grinding. For sheet metal parts requiring tight bend tolerances, see our sheet metal fabrication page.
Well-equipped CNC shops in Egypt can hold tolerances of ±0.005 mm on stable, well-fixtured cuts using carbide tooling and in-process gauging. Wire EDM can achieve ±0.003 – ±0.005 mm profile tolerances. For tighter than this, grinding or lapping is required.
ISO 2768 is a general tolerance standard for linear and angular dimensions that don't have individual tolerance callouts. ISO 2768-m (medium) is ±0.1 mm for dimensions 30–120 mm. ISO 2768-f (fine) is ±0.05 mm for the same range. Always specify the class in your title block.
Yes. Reputable industrial machining suppliers in Egypt have CMM capability or access to third-party metrology labs. Request a First Article Inspection (FAI) report for any new part before releasing production quantities.
Tighter tolerances require more passes, slower feeds, more frequent tool changes, and CMM verification time — all of which add cost. Moving from ±0.05 mm to ±0.01 mm can increase part cost by 30–80% depending on geometry. Specify only what you need.
Tolerance is the permissible variation in a single part dimension. Allowance is the intentional difference between mating parts to achieve a fit (clearance, transition, or interference). Both matter when designing assemblies with moving or press-fit components.
Use ISO fit notation. For an H7/p6 press fit on a 30 mm bore: the bore (H7) is +0.021/0 mm, the shaft (p6) is +0.035/+0.022 mm. This gives 0.001–0.035 mm interference. Include the fit class on both the shaft and bore drawings, and reference the mating part number.
Entag provides CNC turning, CNC milling, EDM wire, EDM spark, and grinding. For extremely tight tolerances or hardened materials, EDM and grinding are the appropriate processes. Submit your drawing at app.entag.co to get a process recommendation.
Entag manufactures precision CNC machined parts for industrial clients across Egypt and the Middle East. Whether you need a single prototype or a full production run, our engineering team is ready to review your drawings and provide a quote.
