Dayton Rogers is committed to supporting in educating the industry on best practices, engineering principles, and commonly used industry terms. Our Glossary helps customers easily define phrases and concepts that they may hear throughout their work. We hope this tool is insightful for you.


Abrasion Resistance – Ability of a coating to withstand rubbing, scraping and eroding forces.

Abrasive – Sharp mineral particles, used for metal removal.

Abrasive Media – Matrix used to carry the mineral particles for the purpose of material removal.

Acidic Etching – Removal of surface contamination by corrosive treatment.

Adaptor – A block used to mount a form tool to a slide.

Air Bending – Forming operation in which a metal part is formed without the punch and die closing completely on the part. (related to Press Brake)

Air Hardening Steel – An alloy steel which will form martensite with high hardness when cooled in air from its proper hardening temperature.

Alloys – Base metal with other metal or non-metal constituents melted together into a new molecular structure.

Alodine – Commercial trade name for a chromate conversion coating over aluminum.

Aluminum Alloy – Pure aluminum which has been melted together with other constituents to achieve specific physical and mechanical properties.

Aluminum Oxide – Hard mineral of aluminum and oxygen Al03 used as an abrasive.

Annealed – Softest possible state of any material.

Annealing, Full – Heat treating process wherein metal is heated to a temperature above its critical range, held at that temperature long enough to allow full recrystallization, then slowly cooled through the critical range.

Anode – Positively charged electrode.

Anodizing – Process of applying a controlled oxide layer to the surface of aluminum.

Archive – The storage of files in the form of tape or disk for long periods of time.

Arcs – Partial circles used to describe rounded corners of material and show bends in material.

Artificially Aged – Hardening process of material accelerated by temperature.

ASCII – Acronym for American Standard Code for Information Interchange.

Austempering – A heat treating operation in which austenite is quenched to and held at a constant temperature usually between 450°F and 800°F until transformation to bainite is complete.

Austenite – The solid solution in which gamma iron is the solvent. Austenite is a structure and does not refer to composition. Austenite is the structure from which all quenching heat treatments must start.

Austenitic Stainless Steel – Non-magnetic stainless steel. Not hardenable through heat treatment; good corrosion resistance.

AutoCAD – A brand name of CAD software prevalent in the marketplace.

Automatic Spinning – The art of forming metal over a mold using an automatic Computer Controlled or Template spinning lathe.

Auxiliary Slide – A brand name of CAD software prevalent in the marketplace.

Automatic Spinning – The art of forming metal over a mold using an automatic Computer Controlled or Template spinning lathe.

Auxiliary Slide – A bed mounted, cam operated slide typically used for forming on a slide forming machine.


Back Gauge – Stop located in the rear of a metal forming or fabricating machine which is used to position the workpiece during an operation.

Banding, Metallic or Non-Metallic – Strong, lightweight ribbons, generally of steel or nylon, applied under tension to strap packages on a pallet.

Bar Coding – Machine readable alphabetic and/or numeric information used for identification of packaged parts.

Bark – An older term used to describe the decarburized skin that develops on steel bars heated in a non-protective atmosphere.

Barrel Tumbling – Process in which parts to be deburred are put together with abrasive material into a many-sided barrel and slowly rotated for prolonged periods for the purpose of burr removal.

Bed –  Bottom transverse structural member on metal forming machine.

Belt Sanding – Metal removing process in which an abrasive impregnated endless cloth belt does the cutting.

Bend Radius – Inside radius of a formed feature.

Bend Relief – Clearance notch at an end of a flange to allow bending without distorting or tearing adjacent material.

Bending – Generally applied to forming. Creation of a formed feature by angular displacement of a sheet metal workpiece. See also Drawing and Forming.

Bi-Planar – Refers to surfaces which meet at an angle in different planes.

Bis – Acronym for bits into sound.

Blank – 1 Sheet metal stock from which a product is to be made. 2 Workpiece resulting from blanking operation.

Blanking – Die cutting of the outside shape of a part.

Bleed-Out – Leaching of entrapped plating solutions, causing surface discoloration and corrosion.

Blind End Fastener – Internally threaded fastener which is manufactured with one end closed such that, when installed, it forms a gas and moisture resistant seal.

Blind Fastener – Fastener which is capable of being permanently installed and used in a workpiece with access from only one side.

Blind Rivet – Rivet which is capable of being installed and used in a workpiece or assembly with access from only one side.

Bottoming – Forming operation in which the punch and the die is closed completely on the workpiece. See Press Brake Chapter.

Bow Distortion – Out of flatness condition in sheet material commonly known as Oil Canning in which, with the edges of the sheet restrained, the center of the sheet can be popped back and forth but cannot be flattened without specialized equipment.

Bps – Acronym for bits per second. Refers to the rate at which a data communications line can transfer information. Bits per second can be faster than baud rate when data compression is used.

Brass – Alloy of copper and zinc.

Breakout – Fractured portion of the cross section of a cut edge of stock. A condition naturally occurring during shearing, blanking, punching and other cutting operations.

Bridges – (see Micro Ties)

Bright Annealing – Annealing work in a protective atmosphere to prevent discoloration as the result of heating. In some atmospheres oxides may be reduced.

Brinnell Hardness Testing – A method of testing the hardness of material. This test is usually used on softer materials and castings in which a carbide ball is pressed into the material for a given period and then removed. The resulting impression is measured for the width along with a value determines hardness of the material.

Brushing or Etching – Mechanical or chemical cleaning of parts before further processing.

Buffing – Polishing method employing soft cloth to carry very fine polishing compounds. Burn Mark Heat discoloration created in the contact area of a welding electrode.

Burnish – Smooth or shiny area above the breakout on a sheared edge. Also called shear or cut band.

Burr – Raised, sharp edge inherent in cutting operations such as shearing, blanking, punching and drilling.

Burr Direction – Side of the stock on which burrs appear.

Burr Height – Height to which burr is raised beyond the surface of the material.

Burr Rollover – Condition of burr displacement resulting from mechanical deburring operation.

Burr-Free – Edge without sharp protrusions.

Bus Bar Copper – Copper with minor alloying constituents and high conductivity used for electrical applications.

Butt – End to end.


C.A.M. – Acronym for Computer Aided Manufacturing.

CAD – Acronym for Computer Aided Design.

Cadmium Plating – Electrolytic process for metal coating in which commercially pure cadmium is the anode.

Cam – A device used to control the motion of slide forming machine slides and attachments, and die components.

Cam Chart – A chart created by the tool designer assuring that the sequence of operations of a complicated part fall within the 360 degree slide forming machine cycle.

Cam Trim – Removing excess material after the part has been drawn or formed. This is done with a cam activated operation, usually as a secondary operation.

Camber – Gradual deviation from straightness of the edge of sheet or coil stock caused during the slitting operation.

Capillary Action – Liquid trapping action caused by the closeness of two surfaces and the surface tension of the liquid.

Carbon Steel – Steel which owes its properties chiefly to various percentages of carbon without substantial amounts of other alloying elements.

Carbonitriding – A heat treatment for steel which adds carbon and nitrogen from an atmosphere rich in such elements.

Carburizing – Adding carbon to the surface of steel by heating it in contact with carbon rich gases.

Case – The surface layer of a steel whose composition has been changed by the addition of carbon, nitrogen, or other material at high temperature.

Case Hardening – A heat treatment in which the surface layer of a steel is made substantially harder than the interior by altering its composition.

Cathode – Negatively charged electrode.

Cellular Dividers – Slotted cardboard sheets designed to be interleaved in a master carton producing individual pockets to separate parts.

Center – The point which is defined midway between the extents of a hole in both the X and Y directions.

Center Tool – See mandrel.

Chain Dimensioning – Drafting practice which dimensions repetitive features from each other rather than a common datum.

Checks – Surface ripples and cracks induced by forming.

Chemical Etching – Removal of metal through chemical erosion process.

Chromate – Post-treatment wash non electrolytic coating which is used over zinc, cadmium, treated aluminum and other plating operations to seal the surface of the coating, prevent oxidation and, in certain cases, improve the electrical characteristics of the coating.

Chromate Conversion – Application of a salt or ester of chromic acid to a metal workpiece by dipping or spraying. The coating is generally used to seal the surface of the workpiece to enhance electrical properties or reduce corrosion.

Circle – A continuous arc starting and ending at the same point.

Clad Shape – A rollformed shape made up of two materials simultaneously fed into the roll forming mill to produce a composite section.

Clamp Marks – Slight indentations at the edge of one side of stock caused by pressure from turret press holding devices. See also Work-holder Mark.

Clock-Spring Material – Alloy steel available in a pre-hardened condition between RC 45 and 52.

CNC – Industry acronym for Computer Numerical Control.

CNC Turret Press – Automatic punch press indexing the material and selecting the intended tool out of the rotary tool holding device turret totally by computer control for piercing, blanking and forming workpieces as programmed.

Coat – Paint, varnish or lacquer applied to a surface in a single application one layer to form a properly distributed film when dry.

Coating System – Consists of a number of coats separately applied in a predetermined order at suitable intervals to allow for drying or curing.

Co-Engineering – Process in which the customer and the supplier review and modify a design to simplify manufacturability of a part.

Coil Breaks Crossbreak – Defective condition of ridges or marks across the width of sheet or coil caused by improper coiling or leveling.

Coining – Compressive metal flowing action. See also, Bottoming.

Cold Rolled Steel – Steel which was reduced to final thickness in the cold state by a rolling mill. Creates a smooth surface with slight skin hardness.

Cold Weld – Defective weld due to improper contact or inadequate heat during welding.

Cold Worked – Material hardened naturally through forming at ambient temperatures.

Cold Working – Plastic deformation of a metal at a temperature low enough so that recrystallization does not occur during cooling.

Collapsible Tool Segmented – A mold having a removable center core which keeps the perimeter pieces in place during spinning.

Color – One aspect of appearance; a stimulus based on visual response to light, and consisting of the three dimensions of hue, saturation, and lightness.

Color Chips – Paint samples.

Color Match – Pair of colors exhibiting no perceptible difference when observed under specified conditions.

Commercial Grade – Standard materials commonly available through supply houses.

Communications Software – A computer program that enables one computer to connect with another computer.

Compound Die – Tool used to pierce, form and blank a part at the same time, with one stroke of the press.

Compress – To condense electronic files for ease of transfer and storage.

Concealed Head Fastener – Fastener installed in a blind hole.

Concentricity – Dimensional relationship of two or more items sharing a common center line.

Conditional Match – Perceived identity of color exhibited by a pair of colors, each with different spectral distribution curves.

Conductive Paint – Organic coating that conducts electrical current.

Conductivity – Ability of a material to conduct electricity or heat.

Connecting Lines – Two lines on a part drawing tangent.

Continuous Radius – A roll formed shape with a continuous curve or sweep in one or more planes.

Continuous Wave – Power output mode of lasers using a constant discharge.

Conventional Spinning – The art of forming metal over a mold using multiple passes and hand pressure.

Conversion Coating – Treatment, either chemical or electrochemical, of the metal surface to convert it to another chemical form. It provides greater corrosion resistance to the metal and increased adhesion of coatings applied to the metal.

Co-Planar – Having all elements, features, dimensions or functions existing in one geometric plane.

Core – The interior part of a steel whose composition has not been changed in a case hardening operation.

Core Hole – Hole diameter required before cutting or forming internal threads.

Corner – Three surfaces meeting at one point.

Corner Radius – Outside radius.

Corrosion Resistance – The ability of a substance to resist deterioration due to a reaction with its environment.

Counterboring – Machining or coining operation to generate a cylindrical flatbottomed hole.

Countersinking – Machining or coining operation to generate a conical angle on a hole.

Critical-to-Function CTF Dimensions – In the absence of dimensional drawings, a means of communicating by CAD dimensions critical to success of the design, tolerance and other non-geometrical information. Generally, simpler than a complete fabrication drawing because of fewer dimensions.

Cross-Hatch Pattern – Repetitive lines crossing each other at an angle, such as a coarsely woven cloth.

Cross-Sections – Sectional views.

Crystalline Structure – Arrangement of molecules in geometric patterns in a solidified material.

Cumulative Tolerance – Progressive accumulation of tolerances resulting from multiple operations or assembly of multiple parts.

Curvature – The tendency for steel strip to retain some of the coil set of the wound coil when it is uncoiled. Also called coil set.

Cut Lengths – Standard sheet sizes of material received from service centers, such as 3′ x 8′ or 4′ x 12′.

Cut-Off – Process by which strips of material or finished parts are cut from a coil or strip of raw material.

Cutoff Press – Any one of several types of cutoff methods in a rollforming line.

Cut-Tape Test – A paint adhesion test consisting of the application of an adhesive tape to a dried coating and rapidly removing the tape with a swift, jerking motion.


Datum – Theoretically exact planes, lines or points from which other features are located on design drawings.

Debur – To remove the sharp, knife-like edge from parts.

Dedicated Tooling – Commonly referred to as hard tooling is tooling made to produce a specific part.

Delamination – Defective surface condition where scale, slag or other impurities not removed during mill processing affect the surface of the sheet.

Die – Tool with a void or cavity which is precisely fitted to a Punch used to shear or form sheet metal parts.

Die Angle – Forming term used to denote the inside angle of a matched punch and die set.

Die Clearance – Amount of space between the punch and die opening per side.

Die Cushion – Large pressurized cylinder, generally housed beneath the bed of a press which is used to apply upward pressure to the lower die.

Die Cut Inserts – Packaging elements, generally of cardboard, which are machine blanked to a specific shape in order to precisely fit a part contour.

Die Marks – Scratches, scrub marks, indentations, galling or burnishing of sheet metal workpieces by tooling.

Dimension – A measurement describing size and/or appearance of a part feature.

Dip Brazing – Metal bonding of parts by molten bath immersion.

Discoloration – l Staining. 2 Changing or darkening in color from the standard or original.

Double Action – Press utilizing two moving elements.

Double Burned – A condition that may occur on a laser wherein the laser essentially produces a feature twice destroying the part’s edge and causing out of dimension condition.

Drain Holes – Holes placed in the part that are nonfunctional except to allow for drainage.

Draw – A term used interchangeably with tempering in the heat treating process.

Draw Ring – Holding device in a die to control material flow and wrinkling during forming.

Drawing – 1 Engineering document depicting a part or assembly. 2 In metal forming, the stretching or compressing of a sheet metal part into a die by a punch to create a 3-dimensional part.

Dry Film Thickness – Thickness of an applied coating after drying or curing.

D-Size – A common drawing size, 22 x 34.

Ductility – Ability of a material to be bent or otherwise formed without fracture.

DXF – Acronym for Drawing Interchange File.


Early Supplier Involvement – Involvement of a supplier during the conceptual development stage of a product.

Edge – A transition between surfaces.

Edge Bulge – Condition resulting from any forming, piercing, hardware insertion or spot welding operation too close to an edge.

Edge Deckle Mill Edge – Waviness of an unslit coil edge, as received from the material supplier.

Edge Pucker – Material extrusion beyond an outside edge through metal forming.

Edge-to-Feature – A dimension between the edge of the part and a feature.

Effective Case Depth – The perpendicular distance from the surface of a hardened case to the deepest point at which a specified level of hardness is attained.

Electrodes – In gas-metal-arc and gas-tungsten-arc welding, a rod or wire acts as an electrical conductor and arc point between the torch and workpiece. In spot welding, electrodes squeeze together metal parts, then conduct current through to create the weld.

Electrolytically Deposited – Depositing of one material on another commonly known as plating.

Electron Beam Welding EBW – Melting and fusing of metals by use of a collimated stream of electrons traveling at close to the speed of light. The kinetic energy from the electrons converts to heat on impact.

Electroplating – Deposition of a thin layer of metal to a workpiece using an electrolytic process.

Electrostatic Spraying – Method of spray painting in which an electrostatic potential is created between the article and atomized paint particles. The charged particles of paint are attracted to and deposited on the articles being painted.

Enclosed Seam and Pocket – Formed, spot welded or welded area that can entrap plating solutions

End Flare – Seen after cut off, caused by the release of residual forming stresses in material being roll formed, where one longitudinal end springs open and the other springs closed.

Entity – A predefined element that you place in a drawing by means of a single command. A single piece of geometry or text.

Extruded Hole – Pierced and formed hole in sheet metal in which the metal has been stretched creating a tubular shape.


Feather Edge – Material thinning toward an edge, creating an irregular knife-edge, tattered appearance.

Feature-to-Feature – Dimension between two features on a part.

Feed Eccentric – A screw-adjusted device used to set the feed length on a slide forming machine.

Feed Unit – An integral part of the slide forming machine, eccentric-driven and cam controlled, that advances either wire or strip in accurate increments.

Female Tool – A mold duplicating the exterior dimensions of the part.

Ferritic – Referring to iron content.

Ferro Magnetic – Various alloys that exhibit magnetic qualities.

Ferrous – Metals containing iron as a major alloying constituent.

Ferro Magnetic – Various alloys that exhibit magnetic qualities.

Ferrous – Metals containing iron as a major alloying constituent.

File Names – A name assigned to a computer file.

Fillet Weld – Joining method of filling an inside edge with welding metal.

Fit-Up – Degree of physical match between two or more components.

Fixture – Tooling designed to locate and hold components in position.

Flame Hardening – A process consisting of heating a desired area, usually localized, with an oxyacetylene torch or other type of high temperature flame and then quenched to produce a desired hardness.

Flange – Formed projection or rim of a part generally used for stiffness or assembly.

Flat or Matte – Coating surface which displays no gloss when observed at any angle; a perfectly diffused reflecting surface.

Flat Pattern – A two dimensional development that represents the part before it is formed into a three dimensional shape.

Flat Wire – Round wire which has been reduced to a flat state with rounded edges.

Floating Fastener – Hardware which allows the threaded portion to move within its particular confines without rotating, to compensate for misalignment.

Flower Diagram -A drawing which superimposes the cross section contour of a roll formed part at each roll station, starting with the flat incoming material and ending with the desired profile. It depicts the anticipated flow of material in the forming process.

Fluting – Series of rounded parallel grooves which shows on the surface of metals.

Flying Die Cutoff – The system used in rollforming to cut the formed shape to length in a continuous operation. Similar in action to a punch press, but designed to allow the die to move in line with the rollformed shape during the cutoff cycle, and to make a cut on the fly.

Follower Block Tail Block – This serves to clamp the work piece to the tool.

Foreign Matter – Anything visually unrelated to the true nature of the substance under examination.

Form – A bend, or the process of bending a metalformed part.

Form Lifter – A cam-operated motion used for lifting the mandrel or forming in an opposite plane.

Formed Tab – Small flange bent at an angle from the body of a metal workpiece.

Forming – Operation converting a flat sheet metal workpiece into a three dimensional part. See, also Bending and Drawing.

Forming Slides – Cam operated units used to drive tools on a slide forming machine.

Forming Tool – A slide mounted tool used for bending on a slide forming machine.

Form-to-Form – Dimension between two forms on a part.

Fourslide Machine – A machine, either horizontal or vertical, used to fabricate formed metal stampings and wire forms, by the action of four forming slides acting upon a stationary mandrel or center tool.

Front Cut-Off – A device driven by a cam that is mounted on the front shaft on a slide forming machine used to severe the blank from the strip before forming.

Functionality – The degree to which the designed part will perform to meet its intended purpose.

Fuse Welded Joint – Welding method without addition of a filler metal, used to generate little, if any eruption above the original surface level.


Galvanic Corrosion – Dissimilar metals in contact with each other in presence of moisture, acting as a battery and causing an electrolytic etching deteriorating effect.

Gas Welding – Melting and fusing metals together by use of an oxygen and flammable gas mixture.

Gauge (Gage) – 1 Instrument for measuring, testing, or registering. 2 Numeric scale for metal thickness.

Gloss – Subjective term used to describe the relative amount and nature of mirror-like specular reflection.

Glossmeter – Instrument for measuring the degree of gloss in relative terms. Such instruments measure the light reflected at a selected specular angle.

Go/No-Go Gauge – Measuring device with two registration elements which determine if a feature to be measured is between two established limits.

Gouge – Surface imperfection, deeper than a scratch, often with raised edges.

Grain Direction – 1 Crystaline orientation of material in the direction of mill rolling. 2 Orientation of a surface finish generated by abrasive method.

Grinding – Process of removing material by abrasion.

Grippers – Material clamping devices often serrated for additional holding force to restrain material during a die operation.

Grit – Mineral particles used for abrasive metal removal.


Half Shearing – Partial penetration piercing, creating a locating button with a height of about 1/2 material thickness.

Hard Tooling – Tooling made for a specific part. Also called dedicated tooling.

Hardenability – The fundamental characteristic of a steel which determines the ease of preventing the transformation of austenite to anything else but martensite during the quench.

Hardware – 1 The physical components of a computer system. 2 Fasteners inserted into a sheet metal part.

Hardware List – Information that should be conveyed to the part supplier specifying part numbers, description and quality of fasteners.

Heat Sink – Good thermal conductor used to remove destructive heat from an area.

Hem Dutch Bend – Edge of material doubled over onto itself for the purpose of safe handling or to increase edge stiffness.

Hold-Down Marks – Slight indentations or scuff marks on one side of the stock which can result from the pressure of hold down devices during shearing operations.

Hole Rollover – Rounding of the top edge of a pierced feature caused by the ductility of the metal, which flows in the direction of the applied force.

Hole-to-Feature – Dimension between the center of a hole and another feature.

Hole-to-Form – Distance from the center line of a hole to the edge of a formed feature.

Hole-to-Hole – Dimension between centers of holes.

Homogenizing – An annealing treatment at a fairly high temperature designed to eliminate or reduce chemical segregation.

Host Computer – An unattended computer that can be accessed by other remote/client computers.

Hot Dip – Application of a metal coating on a substrate by immersion in a molten metal bath.

Hot Rolled Steel – Steel which was rollerformed from a hot plastic state into final shape; characterized by a rough, scaly surface.

HPGL – Acronym for Hewlett Packard Graphics Language.

Hue – 1 Attribute of a color by means of which a color is perceived to be red, yellow, green, blue, purple, etc. White, black and grays possess no hue. 2 The name of a color of a finish, as viewed subjectively.

Hydraulic Press – Machine which exerts working pressure by hydraulic means.

Hydrogen Embrittlement – Loss of ductility of a material due to absorption of hydrogen gas during heat treatment an electrolytic process or during acid cleaning.


IGES – Acronym for Initial Graphics Exchange Specification.

Impact Resistance – Ability to resist deformation from impact.

Inboard Mill – A rollforming machine with a housing only on one end of the roll tooling shaft.

Inclusions – Particles of impurities usually oxides, sulphides, or silicates which separate from the liquid steel and are mechanically held during solidification. In some grades of steel, inclusions are made intentionally high to aid machinability.

Indexable Tool Stations – Special tool positions in a turret press which are equipped with numerically controlled servo drives rotating the punch and die together to profile contours, nibble angles or for other special applications.

Inductance Instrument – Instrument which is used to measure thickness of applied coatings to metal substrates. Unlike magnetic thickness gauges, inductance gauges can measure either conductive or non-conductive coatings on magnetic or non-magnetic substrates.

Induction Hardening – A form of hardening in which the heating is done by induced electrical current.

Inserted Fastener – Variety of pins, nuts, studs, standoffs or special hardware which are installed in a workpiece by inserting it into a specifically punched hole. See chapter on Inserted Fasteners.

Inspection Criteria – Characteristics by which the part will be evaluated both dimensionally and cosmetically.

Interrupted Quench – Stopping the cooling cycle at a predetermined temperature and holding at this temperature for a specific time before cooling to room temperature. Usually done to minimize the likelihood of cracking, or to produce a particular structure in the part.

ISO Drafting Standard – Regulation for the creation of technical drawings published by the International Organization of Standards.

Isothermal Treatment – A type of treatment in which a part is quenched rapidly down to given temperature, then held at that temperature until all transformation is complete.


Lap-Welded Joint – Welded seam in which the two metal pieces to be joined overlap one another.

LASER – Acronym for Light Amplification by Stimulated Emission of Radiation.

Laser Welding – Metal melting and fusing using the energy of a concentrated coherent light beam.

Layer – A CAD file is like a layered stack of clear transparency films with design information on the different layers. They are superimposed on each other. One can look down through all of the layers at once, or only selected layers.

Lead Screw – Drive system which converts rotary to linear motion.

Lead Time – Time required to manufacture a product from order placement until availability. It includes planning, engineering, tool design and construction, acquisition of materials, scheduling, fabrication, finishing and packaging.

Leg Size – Width and height of the filler bead of welding material.

Lever Arms – A scissors-like apparatus used to apply pressure to the spinning blank.

Line Width – Thickness of a line in CAD drawings.

Linear Slide Machine – A vertical slide forming machine with the ability to place several opposing slides arranged in a linear fashion on both the front and back sides of the tooling area providing the ability to produce complicated stampings as well as assemblies.

Lines – A straight line segment between two points.

Load Up – Accumulation and compaction of metal particles between the abrasive grit of a grinding belt disc or wheel rendering it ineffective.

Lock Seam Tube – A hollow closed roll form shape mechanically fastened using the roll form tooling.


Magnetic Thickness Gauge – Device, applicable only to ferrous substrates, which measures the thickness of non-conductive coatings.

Mandrel – Usually a fixed tool on a slide forming machine that metal is formed against by the action of a slide-mounted form tool.

Manganese Mn – Lustrous reddish-white metal of hard brittle and therefore nonmalleable character. Element number 25 of the periodic system. Atomic weight 54.93.

Manufacturability – The degree to which a product can be efficiently and accurately produced using modern manufacturing methods.

Martempering or Marquenching – A form of interrupted quenching in which the steel is quenched rapidly from its hardening temperature to about 450 F, held at 450 F until the temperature is uniform, then cooled in air to room temperature.

Martensite – A ferritic material with distinctive needle like structure which is always present in heat treat hardenable steel.

Martensitic Stainless Steel – Select group of 400 or 500 Series stainless steel which are magnetic and hardenable by heat treating.

Masking – Temporary shielding of a portion of a product to selectively prevent the application of a coating.

Master Carton – Large box, generally 42 in. wide, 48 in. long and 30 in. high, made from heavy test cardboard and designed to fit a standard pallet.

Master Die – Universal tool receptacle for holding changeable tool systems.

Master Document – An original file retained in case of subsequent errors to a copy.

Material Utilization – Extent to which optimal use of material is approached.

Mechanical Assemblies – Part combinations attached by mechanical means using hardware.

Mechanical Fastener – Device clamping two or more components together by mechanical force, such as rivets, screws, etc.

Mesh – Number of holes per inch in sieves used to sort mineral abrasive particles into specific grit sizes.

Metal Thinning – Thickness reduction during any forming operation.

Micro Alloying – Specific alloy combination usually designed for special strength, ductility or flexibility.

Micro Ties – Thin bridges of metal which are left to hold parts in place during turret punch fabrication.

MIG Weld Metal Inert Gas or GMAW Gas Metal Arc Weld – Metal melting and fusing process using a continuous metal consumable electrode with an inert gas around the electrode to shield against oxidation.

Model – 1 Pre-production sample made with limited emphasis on tolerance to test a design concept. See, also, Prototype. 2 A computer graphic depicting exact geometry of a part.

Mold Lines – Lines in a drawing connecting the inner radius and outer radius of a bend and showing the extent of bend.

Multiple Level Forming – A sequence of slide forming operations at different elevations of the center tool.


N/C Press – Numerically controlled press

Nesting – 1 Grouping of identical or different parts in multiples within a workpiece to conserve material. 2 In packaging, stacking of parts whose shape permits one to fit inside another.

Nibble Marks – Slight irregularities at the edge of the stock surface after progressive punching nibbling operations in a turret press.

Nitriding – The process of adding nitrogen to the surface of a steel, usually from dissociated ammonia as the source. Nitriding develops a very hard case after a long time at comparatively low temperature, without quenching.

Nominal – The targeted value for a dimension that defines the size of an ideal part.

Non-Ferrous Metal – Elements and their alloys without iron as a major constituent.

Non-Geometrical – Information not related to the shape of the product. i.e. part number, notes, material lists, tolerances, etc.

Non-uniform Coverage – Inconsistent paint thickness.

Normalizing – The process of heating steel to a temperature above its transformation range, followed by air cooling. The purpose of normalizing may be to refine grain structure prior to hardening the steel, to harden the steel slightly, or to reduce segregation.

Notching – Operation in which the punch removes material from the edge or corner of a strip or blank.

Nugget – Area melted together during resistance welding.


Obround – Contraction of the words oblong and round denoting a punched slot with semicircular ends and straight sides.

Orange Peel – Surface condition characterized by an irregular waviness of a paint finish, resembling an orange skin texture.

Orbital Sanding – Non-straight-line abrasive finish with irregular circular marks.

Organic Coating – Designation of any chemical finish containing carbon.

Orthographic Drawing – A drawing showing a projection of a part in which all the features are visible.

Outboard Mill – A roll forming machine with housings that support both ends of the roll tooling shafts.

Outside Radius – Formed outside radius of a bend.

Overspray – 1 Spray material which may be lost within the spray booth or to the atmosphere. 2 Spray material which subsequently falls on the product. 3 Areas adjacent to coating of surfaces requiring paint.

Oxidation – Chemical reaction between a material and oxygen.

Oxidation Scale – Stained, discolored and flaky surface condition.


Pallet – Wooden platform, generally 42 in. wide, 48 in. deep, and 6 in. high designed to facilitate lift truck handling of parts or packages.

Pancake Die – Simple push-through die for blanking or piercing.

Parametrics – Defining a feature’s size by establishing a geometric relationship between it and other features, instead of defining it with a dimension.

Pattern Direction – Orientation of features or surface patterns on sheets and coils.

Pem Fastener – Self-clinching inserted fastener nut, stud, standoff, pin, blind stand off, etc. made by Penn Engineering & Manufacturing Corp.

Pencil Hardness Test – Method to measure coating hardness based on the scratching of the film with pencil leads of known hardness. The result is reported as the hardest lead which will not scratch or cut through the film to the substrate.

Penetration – 1 Depth of a cutting operation before breakout occurs. 2 In welding, the depth of material through which fusion occurs.

Periphery – The extreme outer edge of part or drawing.

Perpendicularity– Dimensional relationship of a part or datum located at right angles 90° to a given feature.

Phosphating – Pretreatment of metal surfaces by chemical solutions containing metal phosphates and phosphoric acid, to form a thin, inert, adherent, corrosion-inhibiting chemical conversion coating that serves as a substrate for paint coats.

Phosphor Bronze – Copper base alloy with 3.5 – 10% of tin to which phosphorus has been added in a molten state in varying amounts of less than 1% for deoxidizing and strengthening purposes.

Pickled and Oiled – Hot rolled steel with the scale removed through immersion in acid and a follow up rinsing and oiling process for oxidation protection. Also referred to as P&O and HRPO.

Piercing – Punching of openings such as holes and slots in material.

Pigment – Finely ground, natural or synthetic, inorganic or organic, insoluable particles that when dispersed in a liquid vehicle to make paint may provide, along with color, essential properties of a paint opacity, hardness, durability, and corrosion resistance.

Pinch Trim – Trimming excess material from a drawn part at the bottom of the stroke. Leaves drawn shell without an inside burr, but with an outside burr and a thinned edge.

Pitting Inter-Crystalline Corrosion – Gal-vanic attack under moist and acidic conditions between molecular structures of differing alloy content.

Plasma Arc Welding PAW – Specialized process utilizing a non-consumable electrode ionizing an inert gas and increasing temperature to melt the material being welded.

Plastic Deformation– Permanent deformation occurring in forming of metal after elastic limits have been exceeded.

Plate – Sheet steel thicker than 7 gauge 0.179 in. 4.55 mm or sheet aluminum thicker than 3/16 in 4.76 mm.

Point – A piece of geometry at an exact location.

Polishing – Abrasive process in which the surface created takes on a bright reflective finish, scratch-free to the unaided eye.

Postcut Rollforming – A process whereby the raw material is fed into the rollforming mill in coil form with the formed part cut to length. This is the most common roll forming material feeding process.

Powder Coating – 100% solids coating applied as a dry powder and subsequently converted into a film with heat.

Power Spinning  – The art of forming metal over a mold in one pass using hand or hydraulic pressure.

Precipitation Hardenable – Alloy in which a constituent precipitates from its supersaturated solution allowing the material to gain added strength.

Precut Roll Forming – A process whereby the raw material is cut to length prior to entering the roll forming mill and fed into the mill as blanks. Primarily used for low-volume applications.

Prefinished Material – Stock which has been painted or plated prior to fabrication or stamping.

Prenotch/Prepunch Press – A device used to stamp a hole or notch pattern in incoming material on a roll forming line prior to roll forming.

Press Attachment – A bed mounted device on a slide forming machine used for punching, piercing and other press operations.

Press Section – A device that is built into a slide forming machine used for punching, piercing and other press operations.

Primer – First application of a substance capable of adhering to the substrate and providing good adhesion to a subsequent coating.

Programmable Back Gauges – Stops on metal forming machines which can be adjusted during and between cycles by computer numeric control.

Progressive Tool – Die using multiple stations or operations to produce a variety of options. Can incorporate piercing, forming, extruding and drawing, and is usually applied to high quantity production runs.

Projection Welding – Using protrusions on one of the two parts to be resistance welded, creating a positive conductance path.

Prototype – First part of a design which is made to test tolerance capability, tooling concepts and manufacturability.

Pull Down – Area of material next to the penetrating edge of a piercing punch, or die edge of the blanking station, where the material yields, i.e. flows in the direction of the applied force, creating a rounded edge. Also known as roll-over.

Pulse Mode – Intermittent surging of laser cutting power action.

Punch Direction – The direction from which a tool or punch enters the workpiece.

Punch Press – Machine supplying compression force for reshaping materials.

Punch Side – Opposite side from burr side for pierced features; side on which the punch enters the material. The punch side is the burr side for blanked outside contours.


Quenching – Cooling from high temperature, usually at a fast rate.

Quick Change Inserts – Tool sections or parts which may be changed without removing the entire tool from the press.


Ram – Driven movable part of a metal forming machine.

Rear Cut Off – A device on a slide forming machine driven by a cam that is mounted on the rear shaft allowing the removal of a slug from the strip, thus providing the ability to produce a blank with special end shapes.

Repositioning – Operation in turret press fabrication denoting the release of the workholders, movement of the X axis to a new position on the workpiece, and the regripping of the workpiece so that a sheet larger than the X axis table travel can be fabricated.

Reproducibility – Extent to which parts from multiple lots are identical.

Rerolling – Final cold rolling operation, usually done to achieve specific thickness control and improved finish.

Resins – Natural or synthetic basic material for coatings and plastics.

Resistance Spot Welding RSW – Melting and joining action of two adjoining metal surfaces created by the thermal reaction of the metal to the flow of an electrical current forming a weld nugget.

Revision – A subsequent part drawing usually denoting new corrected or improved version.

Revision Description – A written notice describing the nature of changes to a drawing.

Rivet Nut – Internally threaded fastener designed to be used as a rivet from one side of a workpiece or assembly and to provide threads for a screw or bolt to be used in assembly of a mating part.

Rockwell Hardness – An indentation hardness test based on the depth of penetration.

Roll Formed Shape, Hollow – A roll formed shape which is closed by mechanically fastening or welding the two strip edges together.

Roll Formed Shape, Open – A roll formed shape with a linear or curved contour in which the two ends of the shape are not brought together.

Roll Forming – A continuous bending operation in which sheet or strip metal is plastically deformed along a linear axis by being passed through a series of roller dies and progressively shaped to the desired contour.

Roll Stations – Tandem sets of rolls used in roll forming to shape the metal stock in a series of progressive stages to form the desired cross-sectional configuration.

Rotary Slide Machine – A vertical forming machine with the ability to place several forming slides radially around the center tool and produce intricately formed stampings and wire forms.

Roundness – Extent to which a feature is circular.

Run – Sag or accumulation in a paint or finish film prior to curing.

Run Out Flange – Feature on a formed part which is designated by the designer to absorb the tolerance accumulations created by multiple forming operations.


Scale – 1 Thick oxide coating on material normally associated with hot working. 2 Deposit formed from solution directly in place upon a confining surface.

Scallop – Edge condition resulting from nibbling a feature in a turret press.

Scrap – Leftover, unused material relegated to recycling.

Selective Perforation – Hole or slot pattern over a specific portion of a workpiece, normally used for ventilation purposes.

Self-Extracting Archive File – A library file that can automatically create a group of CAD files without requiring the operator to have any special knowledge, or use special software.

Self-Fixturing – Part designed to be self-locating into proper position to another part with the use of built-in locators.

Self-Locking Fastener – Fastener which is machined with interference threads or which has a nylon insert or other locking mechanism to securely hold mating fasteners in high torque or vibration applications.

Semi-Gloss – A gloss range between high gloss and eggshell, approximately 35 to 90 on the 60 degree gloss scale.

Shake Aparts – Term designating a family of parts on a sheet which are held by Micro Ties so small that the parts can be removed from the sheet after CNC punching by simply shaking the sheet.

Shear Spinning – The art of forming metal over a mold in one pass using hand or hydraulic pressure.

Shearing – Cutting force applied perpendicular to material causing the material to yield and break.

Shear-to-Feature – Shearing of an edge of stock to an exact dimension from an already existing feature.

Shielding Gas – Inert gas used for oxidation protection during welding.

Shim Steel – Steel which has been rolled thin to a hard condition and very close tolerance.

Shunting – Short circuiting of a weld current through a previously applied weld nearby.

Shut Height – Clearance in a press between ram and bed with ram down and adjustment up.

Silicon Carbide – Mineral used for abrasive metal removal.

Silkscreening – Printing process using special inks being pressed through a finemeshed fabric which has been prepared by a photo process to let the ink pass through in predetermined patterns of lettering and graphics.

Single Action – Press utilizing one moving element.

Sinkhole – In welding, a dimple on the surface of stock caused by shrinking of the weld during cooling.

Skid Marks Roll Slip – Polished or burnished streaks across the stock surface resulting from improperly set roller driven material processing equipment. Skid marks are transverse to the direction of rolling.

Skin Packaging – Thin poly film which is stretched or heat shrunk over parts for protection or display.

Skin-pass – Single cold rolling process on material after a heat treating process.

Slide Forming – A high-volume stamping process in which a machine with multiple slides sequentially performs various operations i.e. – blanking, piercing, forming, etc..

Slot-to-Form – Distance from a slot edge to the inside edge of a formed feature.

Slug – Scrap from a piercing operation.

Slug Marks – Surface defects caused by scrap being indented into the metal surface.

Soft Tooling – A term generally applied to the fabrication of metal parts using computer controlled technology incorporating CNC turret presses, laser profilers and press brakes.

Solids – The ability of the CAD software to realize that a volume is filled with solid matter. These CAD systems can display a design so that it looks like a solid object. Includes recognition of surfaces and wireframes.

Solution Heat Treat – High temperature process in which an alloy is heated to the suitable temperature for the alloy constituents to be in a totally soluble condition for the purpose of creating a homogeneous alloy. Through rapid cooling the constituents stay in this solution state. Metal so treated is left in a super saturated unstable state and may tend to age harden at ambient temperatures.

Solvent Based – Paint type in which a volatile liquid is used to dissolve or disperse the film-

Spatter – In welding, droplets of matter deposited as contaminants.

Spectral – Spatial arrangement of components of radiant energy in order of their wavelengths, wave number or frequency.

Specular Gloss – Relative luminous fractional light reflectance from a surface in the mirror or specular direction. Expressed as a ratio of incident to reflected light.

Spheroidizing – A heat treating process used to change all of the carbides in steel to rounded particles, or spheroids. A completely spheroidized structure is the softest and most workable structure for any composition.

Spinning Blank – A circular disk made from sheet or plate metal.

Spot Face – Circular flat surface as a bearing area for hardware.

Spring Back – Partial rebounding of formed material caused by its elasticity.

Spring Loaded Panel Fasteners – Inserted fastener which is equipped with a floating captive screw, spring and retainer such that the hardware will remain in the panel, ready for use, when the panel has been disassembled from its mating component.

Squareness – Measure of perpendicularity of adjacent edges or surfaces.

Stack-Ups – Tolerance accumulations.

Stainless Steel – Various ferritic alloys exhibiting high oxidation resistance through the alloying with chromium and nickel.

Stains – Discoloration on the surface of sheet metal, caused during mill processing.

Staking – Method of fastening using displaced material for retention.

Stiffening Rib – Embossed feature in a sheet metal workpiece which is added to make the part more rigid.

Stock Check – A device used to grip the material as the feed retracts, preventing movement of the material during the forming cycle.

Stock Reel – A powered or non-powered device used to support a coil of material as it is fed into the machine.

Stock Straightener – A machine mounted device consisting of a series of adjustable rolls used to straighten wire or strip stock as it comes off the coil.

Stretcher Leveled – A flattening process in which a material is stretched to achieve a desired flatness tolerance.

Strip Edge Forming – The use of a rolling technique to edge roll slit strip with shaped edge rolls to provide an edge finish equal to the material’s surface finish. Also called edge conditioning.

Stripper – Mechanical hold-down device applied to the workpiece during the punching process.

Stripper Marks – Imprints on one side of the stock around pierced holes, caused by punch strippers.

Stripping – Process of disengaging tooling from the workpiece.

Strips – Sheet material, sheared into narrow long pieces.

Stroke – RAM travel from top dead center TDC to bottom dead center BDC.

Substrate – Original material surface to which a coating is applied.

Surface – The ability of the CAD software to recognize that a closed geometric shape represents a surface of a part. Includes recognition of wireframes.

Surface Inclusions – Debris rolled into the skin of material causing a depression or thinly coated pocket.

Surgical Stainless Steel Types – Any of the 300 series stainless steels with an 18% chromium and 8% nickel content. Also includes the PH type of stainless steels.


T.I.R. – Total indicator reading. Absolute sum of all dimensional variance.

Tack Weld – Usually refers to a temporary weld used to hold parts in place while more extensive, final welds are made. In some sheet metal applications, tack welds may provide sufficient strength to eliminate the need for an all-around fillet weld.

Tape – A flexible plastic wound strip coated with magnetic oxide and used for storing electronic data.

Tape Adhesion Test – Conducted by cross hatching the painted surface with a sharp knife in a 1/8 in. grid pattern, applying tape, allowing to sit for a specified period, and then removing with a quick pull perpendicular to the surface of the part.

Tapping – Operation to create internal threads by either cutting or forming.

Temper Designation – Identifying systems to denote the hardness of a particular material.

Tempering – Reheating quenched steel to a temperature below the critical range, followed by any desired rate of cooling. Tempering is done to relieve quenching stresses, or to develop desired strength characteristics.

Tensile Strength – Breaking strength of a material when subjected to a stretching force.

Test File – A CAD system file used to test the compatibility of supplier and customer CAD systems.

Text Files – A file containing words, but no pictures.

Texture – Structure of a surface as it affects appearance or feel.

Thickness – Gauge or depth of material.

Thread Rolling Tap – Tool to generate internal threads by displacing and flowing metal into a thread shape.

TIG Weld Tungsten Inert Gas – Process using a nonconsumable tungsten electrode and a shielding gas, with filler material optional.

Tolerance – Permissible variation from a specification for any characteristic of the product.

Tool mandrel, chuck – The mold from which the part is made.

Tooling Holes – Openings provided in parts for location purposes during production.

Torque – Turning force.

Transfer – Exchanging electronic data from one medium to another.

Transfer Die – Variation of a progressive die where the part is transferred from station to station by a mechanical system. Mainly used where the part has to be free from the strip to allow operations to be performed in a free state.

Transfer Mechanism – Apparatus used to move a part between die stations.

Transfer Protocol – The mutually agreed upon setting used by two computers in data transmission.

Tungsten Electrode – Current carrier made from the metal tungsten for its high heat resistance.

Turret – Rotary tool holding device in CNC punch presses.

Turret Press – Automatic punch press indexing the material and selecting the intended tool out of the rotary tool holding device turret totally by computer control for piercing, blanking and forming workpieces as programmed.

Twist – The rotation of two opposing edges of material in opposite directions.


Ultrasonic – Sound vibration above the audible range.

Undercut – Condition of the stock resulting from welding or grinding below a desired plane.

Unfolded – The act of developing a flat pattern.

UNIX – A computer operating system. The more complex CAD systems require UNIX.


V Punch – V-shaped tool used for angle forming.

V Die – Tool used in conjunction with a V punch.

Vibratory Finishing – Burr removal process in which an appropriate number of parts, depending on part size and abrasive material, is accelerated and decelerated by mechanical means inside of a drum-like enclosure.

Viewing Angle – Inclination from which a surface is observed, i.e. looking straight at the object = 90°.

Viewing Time and Distance – Specified period to inspect a surface condition at a preset dimension from the eye.

Viscosity – Internal friction within a fluid which makes it resistant to flow.

Void – Area in a weld in which insufficient filler material is deposited.


Water-Borne – Generic designation for a variety of organic finishes which indicates that they are compounded with water as a dilutant rather than a volatile organic solvent.

Water-Soluable – Substance which dissolves in water.

Watts per square inch – Measure of speed based on power level of laser cutting machine.

Webs – 1 Material between two openings or edges. 2 See Micro Ties. 3 In some industries, thin material to be punched.

Weld Accessibility – Ease of reaching the weld area with the torch or electrode.

Weld Nut – Internally threaded hardware designed to be spot or projection welded onto sheet metal parts.

Weld Stud – Externally threaded hardware in various lengths in headed and headless version, welded in place.

Weld Distortion – Depression or bulge on surface, caused by thermal expansion.

Weldability – Ability of a material to be fused successfully without special processing.

Weld-To-Edge Distance – Minimum distance from a spot weld to the material edge to create an acceptable spot weld.

Weld-to-Form Distance – Minimum distance from a formed area to electrodes to avoid shorting.

Weld-to-Weld Spacing – Minimum distance between spot welds to avoid shunting through the existing weld spot.

Wet Film Thickness – Thickness of the liquid coating film immediately after application.

Wet-Film Gauge – Device for measuring the film thickness of coatings prior to drying or curing.

Wipe Die – Forming tool using two opposing edges, separated by one material thickness, moving past each other to form material.

Wire Form – A formed metal part made from wire that is usually fabricated on a slide forming machine.

Wire Line – A standard dimension from the bed of the slide forming machine to the material, used in tool layout.

Wireframe – The capability of the CAD software to represent a design as a three-dimensional arrangement of lines and arcs.

Work Hardening – Increase in tensile strength of material resulting from cold working process.

Workholder – Mechanical device which holds a workpiece.

Workholder Mark – Marring of material through the use of clamping device.

Wrinkling – Condition in a paint film appearing as ripples: 1 produced intentionally as a decorative effect or 2 Defect caused by drying conditions or an excessively thick film.

Wrought – Describes material which has been plastically deformed into shape as by mill rolling.


Yield Strength – Maximum stress that can be applied without permanent deformation of material.

YMODEM – A protocol for transferring drawings electronic files.


ZMODEM – A protocol for transferring drawings electronic files