Manufacturing Glossary

55 manufacturing terms defined in plain English. No jargon explaining jargon.

A

AS9100: Quality management standard for the aerospace industry, based on ISO 9001 with additional aerospace-specific requirements. Required by most aerospace and defense customers.

B

Bill of Materials (BOM): A complete list of raw materials, components, sub-assemblies, and quantities needed to manufacture a product. Single-level BOMs list direct materials; multi-level BOMs include sub-assembly breakdowns.
Burr: A raised edge or small piece of material remaining on a part after machining. Removed during deburring operations.

C

CAD: Computer-Aided Design. Software used to create 2D drawings and 3D models of parts and assemblies.
CAM: Computer-Aided Manufacturing. Software that generates CNC toolpaths from CAD models to drive machine tools.
CAPA: Corrective and Preventive Action. A formal process to investigate the root cause of a quality problem, implement a fix, and verify the fix prevents recurrence.
CMM: Coordinate Measuring Machine. A precision measurement device that uses a probe to measure the geometry of physical objects against CAD models or drawings.
CNC: Computer Numerical Control. Automated machine tools controlled by programmed instructions. Includes mills, lathes, routers, grinders, and more.
Concurrent User: A licensing model where you pay for the number of people using the software at the same time, rather than total users. Common in legacy ERP pricing.
Cycle Time: The total time to complete one unit of production, from start to finish of a single operation. Includes setup time (first piece only) and run time (per piece).

D

Deburr: The process of removing burrs, sharp edges, and surface imperfections from machined parts. Done manually or with tumbling, vibratory finishing, or dedicated deburring tools.
Disposition: The decision made about a nonconforming part or material. Options typically include: use-as-is, rework, scrap, or return to vendor.
Drop: The leftover piece of raw material after cutting the needed pieces. Can sometimes be reused for smaller parts if tracked in inventory.
Dwg Rev: Drawing Revision. The version identifier on an engineering drawing. Changes to the drawing increment the revision letter (A, B, C...).

E

EDM: Electrical Discharge Machining. A process that uses electrical sparks to remove material. Wire EDM cuts with a thin wire; sinker EDM uses a shaped electrode. Used for hard materials and complex geometries.
ERP: Enterprise Resource Planning. Software that integrates core business processes — quoting, production, scheduling, inventory, quality, and invoicing — into one system.

F

FAI: First Article Inspection. A complete dimensional verification of the first part produced from a new or changed manufacturing process, documenting that all specifications are met.
Fixture: A device that holds a workpiece in a specific position during machining. Custom fixtures are designed for specific parts; modular fixtures can be reconfigured.

G

G-Code: The programming language used to control CNC machines. Generated by CAM software or written manually by programmers. Defines toolpaths, speeds, feeds, and machine operations.

H

Hot Lot: A job that has been flagged as urgent priority, often due to a customer emergency, production shortage, or late delivery risk. Hot lots typically jump the scheduling queue.

I

ISO 9001: The international standard for quality management systems. Establishes requirements for consistent quality, customer satisfaction, and continuous improvement. Foundation for industry-specific standards like AS9100.
ITAR: International Traffic in Arms Regulations. U.S. regulations controlling the export of defense-related articles and services. Shops handling ITAR-controlled data have specific requirements for data storage and access.

J

Job Costing: Tracking the actual cost of producing a specific job, including labor, materials, and overhead. Comparing actual costs to estimated costs reveals quoting accuracy and profitability.
Job Shop: A manufacturing facility that produces custom parts in small to medium quantities, typically to customer specifications. Each job may have a different routing, material, and setup.

K

Kerf: The width of material removed by a cutting tool (saw blade, laser, waterjet). Must be accounted for when calculating material usage and nesting layouts.

L

Lead Time: The total time from order placement to delivery. Includes procurement lead time (ordering materials), manufacturing lead time (producing the parts), and shipping time.
Lot Tracking: Assigning and tracking unique identifiers (lot numbers) to batches of material or parts through the manufacturing process. Enables traceability from raw material to finished product.

M

Make-to-Order (MTO): A manufacturing strategy where production begins only after receiving a customer order. Common in job shops where each order is unique. Contrasts with make-to-stock.
Margin: The percentage of revenue that is profit. Calculated as (Price - Cost) / Price. A $150 sale on a $100 cost is a 33% margin, not 50% (that's markup).
Markup: The percentage added on top of cost to determine selling price. Calculated as (Price - Cost) / Cost. Not the same as margin — 50% markup equals 33% margin.
Material Cert: A document from the material supplier certifying the chemical composition and mechanical properties of a material lot. Required for traceability in aerospace and regulated industries.
MES: Manufacturing Execution System. Software that tracks and controls production on the shop floor in real-time. Includes work order management, machine monitoring, and production data collection.
MRP: Material Requirements Planning. A system that calculates what materials you need, how much, and when — based on open orders, inventory, and lead times. Generates purchase suggestions to prevent shortages.

N

NCR: Nonconformance Report. A document recording when a part, material, or process fails to meet specifications. Triggers investigation, disposition, and potentially corrective action.
Nesting: Arranging part layouts on sheet material to minimize waste. Used in sheet metal, waterjet, and laser cutting operations. Good nesting can reduce material waste by 10-30%.

O

OEE: Overall Equipment Effectiveness. A metric combining availability, performance, and quality to measure how effectively a machine is being used. 100% OEE means perfect production with no downtime, running at full speed, with zero defects.
Operation: A single step in a manufacturing routing. Each operation specifies a machine or work center, setup time, run time per piece, and any special instructions.
Outside Processing: Work sent to an external vendor as part of the manufacturing process — heat treat, plating, anodizing, NDT, grinding. The part leaves your shop and comes back.

P

Packing Slip: A document included with a shipment listing the contents, quantities, and purchase order reference. Allows the customer to verify they received what was ordered.
Price Break: Different unit prices at different order quantities. Higher quantities get lower per-unit prices because setup costs are amortized across more parts.
Purchase Order (PO): A formal document authorizing a vendor to supply specific materials or services at an agreed price. Creates a binding commitment between buyer and seller.

Q

QMS: Quality Management System. The organizational structure, procedures, and resources needed to manage quality. Documented and audited against standards like ISO 9001 or AS9100.

R

RFQ: Request for Quotation. A document from a customer asking you to provide a price for manufacturing specific parts to their specifications.
RMA: Return Merchandise Authorization. A process for handling customer returns of defective or nonconforming parts. Triggers investigation and potentially replacement or credit.
Routing: The sequence of operations required to manufacture a part, including the machines, setup times, and run times for each step. The backbone of quoting and production planning.
Run Rate: The time to produce one piece during the running (non-setup) portion of an operation. Usually expressed as minutes per piece or pieces per hour.

S

Scrap Rate: The percentage of parts produced that fail to meet specifications and must be discarded. Tracked per operation, per machine, and per part number to identify improvement opportunities.
Setup Time: The time required to prepare a machine for a production run — loading fixtures, setting tools, loading programs, and running first-article verification. Setup time is the biggest cost driver on small runs.
Shop Rate: The fully-loaded hourly cost of operating a machine or workstation, including operator labor, machine depreciation, tooling, consumables, and allocated overhead. Typical range: $65-$150/hour.
SPC: Statistical Process Control. Using statistical methods to monitor and control manufacturing processes. Tracks measurements over time to detect trends before they cause nonconformances.

T

Traveler: A document that accompanies a job through the shop floor, listing operations, specifications, and sign-off points. Also called a router, job traveler, or work order.

V

VMC: Vertical Machining Center. A CNC milling machine with a vertically oriented spindle. The most common type of CNC mill in job shops.

W

WIP: Work in Progress. Parts that are currently in production but not yet complete. WIP represents tied-up capital and should be minimized through better scheduling and flow.
Work Center: A logical grouping of machines or workstations that perform similar operations. Used for scheduling and capacity planning. Example: "CNC Milling" work center containing 5 VMCs.
Work Order: A document authorizing the production of specific parts in a specific quantity. Contains the routing, materials list, and customer requirements. Also called a job order or manufacturing order.