CNC Machining Standards Index
Drawings cite standards; standards drive every dimension, finish, and material callout on a part. This section is a working index: what each major standard actually covers, which clause you usually need, and how the international (ISO, ASME, ASTM), regional (DIN, JIS, EN), and national (GB) systems cross-reference.
Why this matters.
A drawing that cites “ISO 2768-mK” means a specific tolerance class on every uncited dimension. A drawing that cites “ASME Y14.5-2018” means Concentricity and Symmetry symbols are not to be used. If you don’t know the standard, you don’t know the part.
Tolerance & Geometry Standards
- ISO 2768 — General TolerancesTolerance classes f, m, c and v, the linear and geometrical tolerance tables, IT grades IT01–IT18, and what each class actually costs you in scrap
- ISO 286 — Limits and FitsClearance, transition and interference, the ISO hole basis, and what H7/g6, H7/k6 and H7/p6 mean on a drawing — including what a shrink or interference fit does to assembly
- ASME Y14.5 & ISO 1101 — Geometric TolerancingThe geometric tolerance symbols with feature control frame examples, datum rules and the MMC / LMC / RFS modifiers, and how the ASME and ISO systems differ
Surface & Texture Standards
Material Standards
- ASTM & EN Steel DesignationsThe carbon and alloy steel grades that actually get machined — 1045, 4140, 4340, D2, H13 — how the grade callout changes the machining plan, and what a product-form spec such as A36 or A519 is really specifying
- ASTM Aluminum Designations6061, 7075, 5052 and the product-form specs that tell you whether you are looking at plate, sheet, bar or extrusion
- SAE AMS Aerospace MaterialsInconel 718, 625 and Hastelloy C-276 — why aerospace drawings cite an AMS number, and what that changes about the machining plan
Coating, Certification & Quality Systems
- MIL-A-8625 — AnodizingType I, II and III, class and dye-seal designations, and the dimensional consequence of a coating that adds thickness to a toleranced feature
- ISO 9001, AS9100, IATF 16949 & ISO 13485What each quality system adds on top of ISO 9001, which industry expects it, and what it means for the supplier you are actually auditing
- AS9102 — First Article InspectionWhy FAI reports get rejected, the report forms involved, and the balloon numbering conventions a buyer checks before accepting the paperwork
Material Certification
- EN 10204 — Material Test ReportsThe difference between a 3.1 and a 3.2 certificate, who is allowed to sign each, and when a customer can insist on one over the other
- AIAG PPAPWhich of the 18 elements apply to machined parts, the common rejection reasons, and when the automotive industry demands a submission at all
Reading standards.
Most standards cost money, but the scope clause and the table of contents are usually available free from ISO/ASME. We cite the clause numbers we use, so even without buying the full standard you can usually find what you need from the public scope + Wikipedia + this wiki. Always cite the standard and the edition year on your drawing.