Process encyclopedia

Manufacturing processes, from machining to finishing

One record per process: how it works, the materials it suits, typical tolerances and size limits, surface finish, lead time, what drives the price, when to use it and when not to. Every record links to the U.S. shops in the Noramark directory that offer it and to the materials it is used on.

64 processes across 11 groups.

Attach a drawing (PDF or STEP) or describe the part; a U.S. shop that fits quotes it.

CNC machining

Subtractive processes that cut parts from bar, plate and billet.

  • CNC Machining

    CNC machining cuts parts from solid bar, plate or billet on computer-controlled mills and lathes: any machinable material, tight tolerances, from one piece to production.

  • CNC Milling

    CNC milling cuts pockets, holes, bosses and contours into plate and billet with rotating cutters on 3- and 4-axis machining centers, in any machinable material.

  • CNC Turning

    CNC turning makes shafts, bushings, pins and fittings by spinning bar stock against a fixed cutting tool; live tooling adds cross holes and flats in the same setup.

  • 5-Axis CNC Machining

    5-axis CNC machining tilts and rotates the part under the spindle so complex parts are cut in one setup: impellers, aerospace structures, implants and multi-face housings.

  • Swiss Machining

    Swiss machining turns small, long, precise parts from bar on a sliding-headstock lathe: the bar is supported at the cut, so 10:1 lengths hold ±0.005 mm.

  • Screw Machining

    Screw machining turns fasteners, fittings and small round parts from bar on single- and multi-spindle automatics: seconds per part, tens of thousands per order.

  • Wire EDM

    Wire EDM erodes a profile through conductive metal with a thin charged wire: hardened tool steel, carbide and superalloys cut to ±0.005 mm with no cutting force.

  • Sinker EDM

    Sinker EDM burns a shaped electrode into hardened conductive metal to make blind cavities, sharp internal corners and deep ribs no rotating tool can cut, to ±0.005 mm.

  • CNC Grinding

    CNC grinding finishes hardened parts with an abrasive wheel: surface, cylindrical and jig grinding hold ±0.0025 mm, flatness under 0.005 mm and finishes of 0.2 µm Ra.

  • Centerless Grinding

    Centerless grinding sizes round parts and bar between a grinding wheel and a regulating wheel, with no centers or chucks: fast, ±0.0025 mm, roundness under 0.001 mm.

  • Gear Cutting

    Gear cutting makes spur, helical, internal and worm gears by hobbing, shaping and grinding: hobbed gears reach AGMA Q8-Q10, ground gears AGMA Q12-Q14 after hardening.

Cutting

Profiling sheet and plate with a laser, waterjet or plasma torch.

  • Laser Cutting

    Laser cutting profiles sheet and plate with a focused beam and assist gas: fiber lasers cut steel to 25 mm and stainless or aluminum to 20 mm at ±0.1 mm.

  • Waterjet Cutting

    Waterjet cutting slices any material with high-pressure water and garnet abrasive: no heat-affected zone, plate to 150 mm thick, ±0.13 mm, a 1 mm kerf and a slight taper.

  • Plasma Cutting

    Plasma cutting profiles conductive plate with a constricted arc: the cheapest cut through 6-50 mm carbon steel, at ±0.5 mm with a small bevel and a hardened edge.

Sheet metal and forming

Bending, stamping, drawing and rolling sheet, tube and strip.

  • Sheet Metal Fabrication

    Sheet metal fabrication cuts, bends, welds and finishes flat stock into brackets, enclosures and chassis: no hard tooling, fast turns, one piece to thousands.

  • Press Brake Forming

    Press brake forming bends sheet and plate between a punch and a V-die; bend radius, tonnage and springback follow from the die opening and the material.

  • Metal Stamping

    Metal stamping blanks, pierces and forms sheet in a hard tool on a mechanical or hydraulic press: high tooling cost, then parts in seconds at pennies each.

  • Progressive Die Stamping

    Progressive die stamping feeds coil through a multi-station die that cuts and forms a little at every stroke; finished parts drop out at hundreds per minute.

  • Deep Drawing

    Deep drawing pushes a flat blank into a die with a punch to form seamless cups, cans, shells and housings, with depth approaching or exceeding the diameter.

  • Roll Forming

    Roll forming bends coil through a line of roller stands, a few degrees per stand, into a constant cross-section: long uniform profiles, cheap per foot.

  • Tube Bending

    Tube bending forms tube and pipe around a die, rotary draw with a mandrel for tight clean bends; centerline radius, wall factor and ovality set the limits.

Welding and joining

Fusing parts into assemblies and weldments.

  • Welding

    Welding fuses metal parts into one assembly: MIG for speed, TIG for precision, spot for sheet, laser for low heat. AWS D1.1 and D17.1 set the rules.

  • MIG Welding

    MIG welding (GMAW) feeds a continuous wire under shielding gas: the fastest arc process for steel, stainless and aluminum, and the default for fabrication.

  • TIG Welding

    TIG welding (GTAW) uses a tungsten arc under argon with hand-fed filler: the cleanest, most controlled welds on aluminum, stainless, titanium and thin parts.

  • Robotic Welding

    Robotic welding runs a MIG, TIG or laser torch on a programmed arm in a fixtured cell: repeatable welds at 2-4x manual output once the fixture is built.

  • Laser Welding

    Laser welding fuses a joint with a focused beam: deep narrow welds, very little heat and distortion, and high speed, at the price of tight fit-up and fixturing.

Casting

Pouring or injecting molten metal into a mold.

  • Sand Casting

    Sand casting pours metal into a single-use sand mold made from a pattern: low tooling cost, any size, in iron, steel, aluminum or bronze, with rough surfaces.

  • Investment Casting

    Lost-wax investment casting: a ceramic shell around a wax pattern gives fine detail, thin walls and near-net shape in steel, stainless, superalloys and aluminum.

  • Die Casting

    Die casting injects molten aluminum, zinc or magnesium into a steel die under high pressure: thin walls, fine detail and fast cycles behind a $20k-$200k tool.

Forging and extrusion

Shaping metal by force, hot or cold.

  • Forging

    Forging squeezes hot metal between dies into near-net blanks with aligned grain flow: the strongest, toughest parts in steel, aluminum, titanium or nickel.

  • Aluminum Extrusion

    Aluminum extrusion pushes a hot billet through a steel die into long, constant-profile shapes: low die cost, 6063 and 6061, cut to length and machined.

Plastic molding

Molding thermoplastics at volume.

  • Injection Molding

    Injection molding shoots molten plastic into a steel or aluminum mold: identical parts in seconds at cents each, once a $3,000-100,000 mold is paid for.

  • Overmolding

    Overmolding molds a second material onto a first: soft TPE on rigid plastic by two-shot or pick-and-place, and plastic around metal by insert molding.

3D printing

Building parts layer by layer in metal or polymer.

  • 3D Printing

    3D printing builds parts layer by layer from CAD. Choosing between FDM, SLA, SLS/MJF and metal powder bed fusion by material, tolerance, finish and cost.

  • Metal 3D Printing

    Metal 3D printing (laser powder bed fusion, DMLS) makes dense titanium, stainless, Inconel and AlSi10Mg parts with internal channels, HIPed and machined.

  • SLA 3D Printing

    SLA 3D printing cures liquid resin with a UV laser for the finest detail and smoothest surface: cosmetic prototypes, clear parts and casting patterns.

  • FDM 3D Printing

    FDM 3D printing extrudes thermoplastic filament layer by layer: the cheapest, largest prints, from PLA prototypes to Ultem 9085 and PEEK parts.

  • SLS 3D Printing

    SLS and HP MJF fuse nylon powder into tough PA12 and PA11 parts with no supports: functional prototypes and production runs into the low thousands.

Finishing and coating

Anodizing, plating, painting and surface treatments.

  • Anodizing

    Anodizing grows a hard, dyeable aluminum oxide layer on aluminum parts, 8-25 µm thick, for corrosion resistance, colour and a durable satin finish.

  • Hardcoat Anodizing

    Hardcoat anodizing (MIL-A-8625 Type III) grows a 25-75 µm oxide layer on aluminum at 60-70 HRC equivalent, for wear surfaces, slides, pistons and tooling.

  • Powder Coating

    Powder coating sprays dry resin powder onto grounded metal and bakes it into a tough 50-100 µm film: the durable colour finish for steel and aluminum parts.

  • Plating

    Plating deposits a thin metal layer (zinc, nickel, chrome, tin, gold, silver) on a part for corrosion resistance, wear, conductivity or appearance. Which metal, and how thick, is the decision.

  • Electroless Nickel Plating

    Electroless nickel deposits a uniform, hard nickel-phosphorus layer on any shape without electric current: corrosion and wear protection that holds size on steel and aluminum.

  • Zinc Plating

    Zinc plating puts a thin sacrificial zinc layer (5-25 µm) on steel parts, usually with a chromate passivate: the cheapest corrosion finish for hardware and small parts.

  • Hard Chrome Plating

    Hard chrome plating deposits 25-250 µm of chromium at 850-1,050 HV on steel shafts, rods, molds and bores: the classic wear and salvage coating, ground to size after plating.

  • Nickel Plating

    Electrolytic nickel plating deposits a bright decorative or a ductile engineering nickel layer on steel, copper and zinc parts, 5-250 µm thick, alone or under chrome.

  • Passivation

    Passivation cleans free iron off stainless steel in a nitric or citric acid bath so its chromium oxide film reforms intact. No coating, no dimensional change: it restores corrosion resistance.

  • Black Oxide

    Black oxide converts the surface of steel to a thin black magnetite film in a hot alkaline bath. Near-zero thickness, a matte black look and mild rust resistance once oiled or waxed.

  • Chem Film (Chromate Conversion Coating)

    Chem film (MIL-DTL-5541, Alodine) is a chromate conversion coating on aluminum: sub-micron, conductive, corrosion resistant, and the standard paint base. Clear or gold.

  • E-Coating (Electrocoating)

    E-coating deposits paint from a water bath onto a charged metal part: an even 15-30 µm epoxy or acrylic film that reaches inside tubes and recesses.

  • Hot-Dip Galvanizing

    Hot-dip galvanizing dips fabricated steel in molten zinc at about 450 °C, bonding a 50-150 µm zinc coating that protects outdoor steel for decades.

  • Bead Blasting

    Bead blasting throws glass bead or grit at a part to clean it, hide tool marks and leave a uniform matte finish: the usual prep before anodize and paint.

  • Vibratory Finishing

    Vibratory finishing tumbles parts in abrasive media to deburr, radius edges and smooth surfaces in bulk: low cost per part, little control per feature.

  • Electropolishing

    Electropolishing removes a thin, controlled layer from stainless steel in an acid bath under current, leaving a bright, smooth, clean and passive surface.

  • Shot Peening

    Shot peening blasts a part with round steel, ceramic or glass shot at a controlled Almen intensity, putting the surface in compression for fatigue life.

Heat treating

Changing hardness, strength and stress state with heat.

  • Heat Treating

    Heat treating changes hardness, strength and internal stress with controlled heating and cooling: quench and temper, normalize, or solution treat and age.

  • Carburizing

    Carburizing diffuses carbon into low-carbon steel (8620, 1018), then quenches it: a 58-62 HRC wear case over a tough core for gears, pins and shafts.

  • Nitriding

    Nitriding diffuses nitrogen into steel below its transformation range: a hard, wear- and fatigue-resistant skin with no quench and very little distortion.

  • Induction Hardening

    Induction hardening heats only a band of a steel part with a copper coil and quenches it: a 1-6 mm hard case on shafts, pins and gear teeth in seconds.

  • Vacuum Heat Treating

    Vacuum heat treating hardens, tempers and ages parts in an evacuated furnace with a gas quench: bright, decarb-free tool steel and aerospace parts.

  • Stress Relieving

    Stress relieving heats a part below its transformation range and cools it slowly, so welds and machined parts stop moving, with little change in hardness.

  • Annealing

    Annealing heats metal and cools it slowly to soften it, restore ductility after cold work and improve machinability: full, process and solution anneals.

Inspection and testing

Proving parts meet the drawing.

  • CMM Inspection

    CMM inspection probes a part on a coordinate measuring machine to verify dimensions and GD&T, and documents it in first article (AS9102) and PPAP reports.

  • Nondestructive Testing (NDT)

    NDT finds cracks, porosity and inclusions without damaging the part, by penetrant, magnetic particle, ultrasonic, X-ray or eddy current inspection.