Precision machining, like any specialized field, has its own unique vocabulary. To outsiders—be they friends, family, or customers—machining lingo can seem like a foreign language. This guide aims to demystify machining jargon, making it accessible to everyone.
Category 1: Metallurgical Terms
These terms come from physics, engineering, and chemistry, with precise definitions critical to manufacturing.
- Alloy: Any metal formed by mixing other metals.
- Ferrous: Metals containing iron (non-ferrous metals do not contain iron).
- Induction Heating: A contactless heating process where a conductive object (like metal) interacts with a magnetic field, used in foundries and for shrink fit toolholders.
- Metrology: The science and practice of measurement.
- Permeability: A material property allowing gases to pass through a solid surface, often used to describe mold material.
Acronyms streamline communication in the manufacturing world.
- APQP (Advanced Product Quality Planning): A process for product development and production, initially for the automotive industry, now used widely in manufacturing.
- CNC (Computer Numerical Control): Automating machining processes using computer software and hardware.
- DFM (Design for Manufacturability): Engineering practice focusing on making products easier to manufacture.
- ECN (Engineering Change Notice): Document noting and authorizing design changes.
- GD&T (Geometric Dimensioning and Tolerancing): System of symbols and values in engineering drawings to communicate tolerances.
- FMEA (Failure Mode Effects Analysis): Analytical system to identify and rank potential design failures.
- PPAP (Production Part Approval Process): Part of APQP, showing a supplier can meet production requirements.
- Ra (Roughness Average): Measurement of surface finish, averaging the height of microscopic peaks and valleys.
This mix of scientific terms and slang describes unique machining situations.
- As-Cast Condition: State of a casting that hasn’t been machined or processed.
- Location Surface: Reference point on a casting for measurements.
- Machine Stock: Extra metal remaining on a part’s surface for machining.
- Near Net Shape: Products, often castings, needing little or no finishing.
- Roughing: Rapid material removal to create a workpiece approximating finished dimensions.
- Fixturing Tooling: Device holding a part for tool access and rigid support during machining.
Category 4: Alternate Uses of Common Words
Machinists use familiar words in new contexts.
- Allowance: Permissible difference in mating parts’ dimensions for a proper fit.
- Apron: Part of the lathe carriage protecting the mechanism and containing controls.
- Bed: Principal machine tool component supporting and aligning other parts.
- Boring: Process to enlarge and finish pre-existing holes.
- Boss: Elevated area of a casting allowing a hole to be machined.
- Stock: Unfinished materials used to make parts in a machine tool.
- Tap: Tool to cut inward threads into a hole.
- Ways: Linear or v-shaped surface supporting and guiding moving parts.
By familiarizing yourself with these terms, you'll better understand and communicate with precision machinists.
