Tool and Die Shops Industry Terminology

5S

A workplace organization method (Sort, Set in order, Shine, Standardize, Sustain) used to reduce waste, improve safety, and increase efficiency in shops.

- We 5S'd the EDM area before the ISO audit. - The team did a 5S red-tag event and freed up two pallets of space. - Daily 5S walks caught a coolant leak near the CNC cells.

APQP

Advanced Product Quality Planning; a structured method, common in automotive, to ensure product quality from concept through production.

- The OEM requires full APQP with PPAP level 3 for this die set. - We’re in APQP phase 2; process flow and PFMEA are due Friday. - APQP aligned our tooling timeline with the customer’s SOP date.

BOM

Bill of Materials; a complete list of components, materials, and subassemblies required to build a tool, die, or mold.

- Add the lifters and return springs to the BOM before we release the order. - The ERP exploded the BOM and flagged two items as long-lead. - A clean BOM prevented shortages during die assembly.

CMM

Coordinate Measuring Machine; precision metrology equipment that measures geometries of parts and tools using a probe in 3D space.

- Send the die shoes to CMM for a full GD&T report. - The CMM verified true position on the punch cluster within 0.025 mm. - We programmed the CMM offline from the CAD model.

CNC

Computer Numerical Control; automated machine tools (mills, lathes, grinders) controlled by programmed code for precise, repeatable machining.

- Run the cavity blocks on the 5-axis CNC overnight. - CNC hard-milling saved a burn and a grind on that insert. - We updated the CNC to accept probing macros for in-process checks.

Cpk

Process capability index; measures how well a process can produce within specification limits relative to its variability and centering.

- Our Cpk on the critical diameter is 1.67 after tool change optimization. - The customer wants Cpk ≥ 1.33 on hole location from the progressive die. - Low Cpk triggered a corrective action and fixture redesign.

D2 Tool Steel

A high-carbon, high-chromium cold-work tool steel known for high wear resistance and good dimensional stability after heat treatment.

- We specified D2 for the blanking punches due to wear resistance. - The D2 inserts were cryo-treated to extend life. - Switch from D2 to powdered metal for the high-volume station?

Datum

A reference feature (plane, axis, point) from which measurements, tolerances, and setups are established in design, metrology, and machining.

- Use the heel block face as datum A for CMM inspection. - The fixture pins establish the primary datum for drilling. - The drawing’s datum scheme drives our machining setup sequence.

Deburring

Removing sharp edges and burrs from machined or stamped parts using manual tools, abrasives, tumbling, brushes, or specialized machines.

- Send the die buttons for tumble deburring before assembly. - A quick hand deburr eliminated part edge chipping. - We added a deburring op after wire EDM to remove recast burrs.

DFMA

Design for Manufacturability and Assembly; engineering approach that simplifies part geometry and assembly to reduce cost, time, and defects.

- DFMA led us to combine two inserts into one standard block. - With DFMA, we added draft to simplify molding and ejection. - DFMA review cut machining hours by 20% via standard components.

Die Set

The assembly of upper and lower plates, guide posts, and bushings that supports and aligns stamping die components through the press stroke.

- Order a standard 12x18 die set with ball cage guides. - The die set alignment was checked with a blue check at shut height. - Upgrading the die set to precision pins improved part location.

EDM (Electrical Discharge Machining)

A non-contact machining process that removes material using controlled electrical sparks between an electrode and the workpiece in a dielectric.

- Burn the square pockets by sinker EDM to avoid corner radii. - Wire EDM the profile and leave 0.01 mm for a skim cut. - EDM recast was removed by a light stone and polish.

Ejector Pin

A mold component that pushes the finished plastic part out of the cavity during the ejection phase of the molding cycle.

- Add vent flats to the ejector pins to prevent vacuum marks. - The ejector pin layout was adjusted to reduce part deformation. - We nitrided the ejector pins for wear resistance.

ERP

Enterprise Resource Planning; integrated software system for managing orders, scheduling, inventory, costing, and shop floor execution.

- ERP shows P20 stock is below safety level; place a PO. - Time tickets feed directly from the machines into ERP. - We tied RFQ costing to ERP routings for accuracy.

FAI (First Article Inspection)

Initial comprehensive inspection of the first production parts to verify that drawings, specs, and processes have been correctly implemented.

- Ship the FAI parts with full CMM reports and certs. - FAI caught a gate vestige issue before SOP. - We delayed FAI until the tryout hits nominal dimensions.

Feed Rate

The linear speed at which the cutting tool advances through material, often expressed as mm/min or inches per minute, or per-tooth values.

- Increase feed rate to improve chip load and reduce rubbing. - The CAM post set feed rate at 1,200 mm/min for roughing. - Adjust feed per tooth to maintain tool life in H13.

Fixture

A device designed to securely locate and hold a workpiece during machining or inspection, ensuring repeatability and accuracy.

- Build a modular fixture for the cavity finishing op. - The probing routine locates the part relative to the fixture keys. - A rigid fixture eliminated chatter during roughing.

G-Code

The common CNC programming language using commands (e.g., G1 linear move, G2 arc) and M-codes to control machine motion and functions.

- The G-code includes a probing macro before machining. - We added G43 and correct tool length offsets to avoid crashes. - Optimize G-code arcs to smooth the toolpath in corners.

GD&T

Geometric Dimensioning and Tolerancing; a symbolic system defining allowable part geometry variation relative to datums for functionality and interchangeability.

- True position and flatness callouts drive our inspection plan. - The GD&T scheme allowed more tolerance through datum shifts. - We trained operators to interpret GD&T on cavity prints.

Gate

In injection molding, the small opening where molten plastic enters the cavity from the runner system, influencing fill, appearance, and shear.

- Move the gate to reduce weld lines on the cosmetic face. - We changed to a sub-gate to minimize vestige. - Balancing gates helped fill both cavities evenly.

H13 Tool Steel

A chromium-molybdenum hot-work tool steel used for molds and dies exposed to high temperatures; good toughness and thermal fatigue resistance.

- Specify H13 for hot runners and core pins due to thermal cycling. - We hard-milled the H13 to 52 HRC with coated carbide. - Nitriding H13 improved wear without distorting the core.

Hardness (HRC)

A material’s resistance to indentation; in tooling often measured on the Rockwell C (HRC) scale after heat treatment.

- Target 58–60 HRC on D2 punches after temper. - The cavity blocks read 50 HRC on the Rockwell tester. - Hardness drop indicates improper tempering; reheat treat.

Heat Treatment

Thermal processes (hardening, tempering, annealing, stress relieving) applied to tool steels and components to achieve desired properties.

- Quench and temper the die insert to 60 HRC. - We stress-relieved the base plate after roughing. - Improper heat treatment caused distortion in the shoe.

HSM (High-Speed Machining)

Machining strategy using high spindle speeds, lighter radial engagement, and optimized toolpaths to increase metal removal and surface quality.

- Use HSM toolpaths with small stepovers for hard milling. - HSM reduced cycle time by 30% on the cavity surfaces. - Stable holders are crucial for HSM in hardened steel.

Jig

A workholding device that also guides the tool (e.g., drill bushings), historically used to ensure repeatable hole/location placement.

- A drill jig with bushings ensured hole location on the plate. - The weld jig holds the frame square during tack-up. - We replaced the manual jig with a CNC fixture for accuracy.

Kanban

A visual pull system that signals replenishment of materials or work, helping control inventory and synchronize production flow.

- We set a two-bin Kanban for standard punches and pins. - Kanban cards trigger reorders of EDM wire. - Kanban leveled the flow between design and machining.

Kerf

The width of material removed by a cutting process (e.g., saw, EDM wire), affecting dimensions, nesting, and compensation.

- Compensate for wire EDM kerf at 0.25 mm. - Saw kerf waste was factored into the raw stock estimate. - Kerf taper required a skim pass for accuracy.

Lead Time

The elapsed time from order to delivery, including design, procurement, machining, assembly, and validation steps.

- The mold lead time is 12 weeks including tryout. - Long-lead items like steel and hot runner drive total lead time. - Reducing setup time cut internal lead time by two days.

Lean Manufacturing

A philosophy and toolkit focused on eliminating waste, improving flow, and delivering value with fewer resources.

- Lean reduced travel between EDM and polishing by cell layout. - We ran a kaizen on die changeover to cut waste. - Lean metrics improved OEE and shortened lead times.

Lights-Out Machining

Unattended, automated machining where equipment runs without operators, often overnight, using robust fixturing, probing, and monitoring.

- We queued finishing ops for lights-out over the weekend. - Probing and tool monitoring enable safe lights-out runs. - Lights-out machining boosted spindle utilization to 80%.

MQL (Minimum Quantity Lubrication)

A lubrication method applying a very small amount of oil mist directly to the cutting zone, reducing coolant consumption and cleanup.

- Switch to MQL on aluminum plates to reduce coolant costs. - MQL improved tool life without flood coolant mess. - The MQL nozzles were tuned for the slotting op.

MRP

Materials Requirements Planning; calculates material needs and timing based on demand, BOM, and inventory to plan purchasing and production.

- MRP exploded the BOM and scheduled raw steel orders. - We used MRP to align material availability with due dates. - Errors in MRP lead times caused past-due jobs.

OEE

Overall Equipment Effectiveness; metric combining Availability, Performance, and Quality to show how effectively equipment is used.

- Our OEE on the CNC cell improved from 55% to 68%. - Downtime from setups killed OEE last quarter. - Adding SMED raised availability and boosted OEE.

On-Time Delivery (OTD)

The percentage of orders delivered by the promised date, a key customer service and scheduling performance metric.

- We hit 98% OTD after adding a second tryout press. - OTD slipped due to a supplier heat-treat delay. - Weekly load leveling improved OTD on small tools.

P20 Tool Steel

A prehardened mold steel (typically ~28–32 HRC) commonly used for injection mold bases and cavities for moderate production volumes.

- Specify P20 for the mold base; it machines well prehardened. - We textured the P20 cavity after polishing to SPI-B. - P20 is adequate for this volume; H13 not required.

PPAP

Production Part Approval Process; documentation and validation package used (especially in automotive) to prove a production process can meet requirements.

- Submit PPAP with control plan, FMEA, and capability studies. - The customer rejected PPAP pending gate vestige correction. - PPAP level 3 requires full dimensional and material certs.

Progressive Die

A stamping die that performs multiple operations in sequence as strip stock advances, producing a finished part each press stroke.

- The progressive die blanks, pierces, and forms in five stations. - Strip layout optimization reduced material waste in the progressive die. - We added a sensor to detect misfeeds in the progressive die.

Punch

In stamping, the component that shears or forms material by entering the die opening; also general term for creating holes or features.

- Increase punch-to-die clearance to reduce burrs. - The punch chipped due to misalignment; re-bush the guide. - We coated the punches with TiAlN for wear resistance.

Ra (Surface Roughness)

Arithmetic average roughness; a common quantitative measure of surface texture used to specify and verify surface finish.

- Finish to Ra 0.8 µm on the cavity faces. - The grinder achieved Ra 0.2 µm with a fine wheel. - Higher Ra on slides increased wear; we polished to spec.

RFQ

Request for Quotation; a customer’s formal request for pricing, lead time, and proposal details for a tool, die, or machining service.

- The RFQ requires two tool design concepts and lead-time options. - We priced the RFQ using standard die set components to cut cost. - RFQ notes call for PPAP and 12-month spare parts.

Scrap Rate

The percentage of parts or material discarded due to defects or nonconformance, indicating process and tooling performance.

- Scrap rate dropped after we stabilized the piercing station. - High scrap rate triggered a tooling maintenance review. - We track scrap rate by operation in ERP.

Setup Time

The time required to prepare a machine or press for a new job, including changeovers, fixturing, tooling, offsets, and program loads.

- Setup time on the 5-axis was cut by using zero-point fixtures. - Long setup time is hurting OEE and throughput. - Presetting tools offline reduced setup time by 40%.

SMED

Single-Minute Exchange of Die; a methodology to reduce changeover times by separating internal and external tasks and streamlining steps.

- SMED converted internal die clamp steps to external with quick-change. - A SMED event halved our press changeover time. - Color-coding tooling carts supports SMED practices.

SPC

Statistical Process Control; using control charts and data analysis to monitor and control processes, preventing defects.

- SPC charts show drift in hole diameter after 5,000 hits. - We added SPC on shut height to track press performance. - SPC signaled a special cause tied to a worn punch.

Sprue

In molding, the primary channel through which molten plastic enters the runner system; affects fill, pressure, and part quality.

- The sprue diameter was increased to reduce shear heating. - We changed to a hot sprue to shorten cycle time. - Sprue break issues were solved by adding a puller.

Tolerance

The allowable variation from a specified dimension or geometry that ensures function and interchangeability; defined on drawings and models.

- The tolerance on part flatness is 0.05 mm per GD&T. - Tight tolerance here drives grinding cost; can we relax it? - Stack-up analysis shows the tolerance scheme is feasible.

Toolpath

The programmed route a cutting tool follows in CNC machining, generated by CAM to achieve the desired geometry and finish.

- Optimize the 3D toolpath to avoid tool dwell marks. - Trochoidal toolpaths lowered cutting forces in D2. - We verified the 5-axis toolpath with machine simulation.

Tryout

Initial testing of a new or modified tool/die/mold in the press or molding machine to validate function and make adjustments.

- The first tryout showed springback; adjust the form station. - We booked the tryout press for Wednesday afternoon. - Tryout data informed our final die spotting steps.

Wire EDM

A type of EDM that uses a continuously fed, electrically charged wire to cut precise profiles through conductive materials.

- Wire EDM the die openings with 0.2 mm wire and two skim cuts. - Wire EDM allowed tight clearance with no burrs. - We compensated wire EDM taper on tall punches.

Workholding

Methods and devices used to secure and locate workpieces during machining, including vises, clamps, fixtures, pallets, and zero-point systems.

- Invest in zero-point workholding to speed changeovers. - Poor workholding caused chatter on the finishing pass. - Modular workholding let us run families of parts efficiently.