Reference

Fabrication Glossary

Plain-English definitions of 151 metal-fabrication terms used in gate, fence, balustrade, and drawing work — from battened gates and RHS to orthographic views and pool-fence compliance. Each entry links to the CAD60 models that use it and to the relevant Australian Standard.

A

Aluminium: A lightweight non-ferrous metal that doesn't rust. Used for gate battens, slats, louvres, and lightweight residential gate frames.
Aluminium extrusion: An aluminium product made by pushing heated alloy billet through a shaped die. Source of all standard batten, slat, louvre, and rail profiles.
Aluminium slat fence: A fence built from aluminium slat extrusions on steel or aluminium posts. Low maintenance, modern look. Ubiquitous in suburban Australia.
Anchor bolt: A bolt or threaded stud designed to be cast into wet concrete, providing a fixed thread for a base plate to bolt down to once the concrete cures.
Anti-lift bracket: A steel hook on a cantilever gate that grips under the rollers. It stops anyone lifting the gate up and off its rollers.
AS 1428.1 (disability access): The Australian standard for design for access and mobility. For pedestrian gates, sets the minimum 850 mm clear opening for compliant access.
AS/NZS 1554 (welding of steel structures): The Australian/NZ standard for welding structural steel. Covers welder qualifications, weld procedures, inspection, and quality categories.
AS/NZS 5131 (structural steelwork construction): The Australian/NZ standard for the construction of structural steelwork, with four construction-category levels (CC1 to CC4) of inspection rigor.

B

Balustrade: A protective barrier of vertical members fixed atop a balcony, deck, or stair edge to prevent falls. Minimum 1 m height in residential Australia.
Battened gate: A welded steel frame infilled with vertical battens at small gaps. The standard residential look in Australia: privacy without total opacity, no wind catch.
Bi-fold gate: A driveway gate that folds in half on a hinged centre joint, halving the swing arc. Used where opening width is wide but swing room is short.
Bottom rail: The bar across the base of a gate frame. On a sliding gate it is heavier because it carries the rollers; on a swing gate it matches the top rail.
Bottom roller: A wheel fixed under a tracked sliding gate. It runs along the V-track or inside the U-track and carries the gate's weight.
Bracing bar: A horizontal steel tube welded behind battens or slats for extra rigidity. Hidden from the gate face but stiffens the infill against wind.
Butt hinge: A pair of flat plates joined by a pin barrel, fixed to the gate stile and the post. The standard low-cost hinge for light pedestrian gates.
Butt weld: A weld that joins two members end-to-end in the same plane. The workhorse joint for splicing tubes and joining frame extensions.

C

Cantilever gate: A sliding gate with no track on the ground. It hangs from rollers on a post and balances on a tail. Good for a clean, clear driveway.
Cantilever rail: The strong beam along the bottom of a cantilever gate. It rides on rollers fixed to a post, so the gate hangs in the air with no track on the ground.
Catch plate: A welded plate on the latch side that stops a swing gate over-swinging past the closed position. Also a target for the latch tongue.
Catcher post: The post on the far side of a sliding-gate opening. It catches the front edge of the gate and holds it straight when the gate is fully shut.
Centre line: A long-dash-short-dash line showing the symmetric centre of a feature (a hole, a shaft, a symmetric gate face) or the axis of a rotation.
Chainwire (chainlink) fence: A fence made from interwoven steel wire forming a diamond pattern, hung from posts with top and bottom tension wires. Cheap, transparent, ubiquitous.
Chemical anchor: A threaded stud bonded into a hole drilled in concrete using a two-part epoxy or vinylester resin. The strongest retrofit anchor for steel-to-concrete fixings.
Circular Hollow Section (CHS): Cold-formed steel tube with a round cross-section. Used for handrails, posts, and any application where a circular profile suits the function.
Clear opening: The width of the gap a gate has to cover, measured between the inside faces of the two posts. The first number you take for sizing any gate.
Coach bolt (carriage bolt): A bolt with a domed mushroom head and a square shank under the head that bites into timber to stop the bolt rotating during tightening.
Colorbond fence: A pre-painted steel sheet fence (BlueScope Colorbond) with sheets sliding into channelled steel posts. The standard residential boundary fence in Australia.
Concreted post: A gate post set directly into a concrete footing. The strongest and most permanent post mounting for swing and sliding gates.
Continuous weld: A weld that runs uninterrupted along the full length of a joint. The default for structural and load-bearing gate joints.
Core-drilled post: A balustrade or fence post fixed into a hole core-drilled through the slab and grouted in place. Strongest non-cast retrofit fixing into concrete.
Counterweight section: The part of a cantilever gate that sticks out past the post when the gate is shut. It balances the gate's weight so it sits steady on the rollers.
Crimped Spear Tip: A pressed-flat pyramid tip formed from the top end of a palisade spear shaft. The cheapest tip option: no separate fitting, just press and weld closed.
Cross brace: A diagonal steel member welded inside a gate frame to resist racking (the frame trying to deform from a rectangle into a parallelogram).
Cutting list (BOM): A list of every steel section in the gate, with length, count, and any cut-angle. Feeds straight into the workshop cold saw.

D

Datum line: A line that is perfectly flat and level. You stretch it across an opening and measure from it, so every measurement starts from the same place.
Detail view: A magnified view of a small region of a parent drawing, used to show fine geometry that would be cluttered or unreadable at the parent view's scale.
Dimension line: A line with arrowheads at each end that measures the distance between two extension lines on an engineering drawing.
Double rake: A gate built for ground where the top and the bottom both slope. You measure four heights from one level line: up to the top and down to the bottom on each side.
Double swing gate: A two-leaf swing gate where each leaf swings independently. Used to span openings wider than a single leaf can carry.
Drawing scale: The ratio between dimensions on the drawing and dimensions on the actual part. Common gate-trade scales are 1:50, 1:25, 1:20, 1:10.
Drive rack: A toothed steel bar fixed along the bottom of an automatic sliding gate. The motor's gear grips the teeth and walks the gate open and shut.
Driveway gate: A vehicle gate spanning a driveway entry. Built as a single swing, double swing, sliding, cantilever, or telescopic gate depending on the site.
Drop bolt: A vertical bolt mounted on the leading edge of a gate that drops into a ground sleeve to lock the gate when closed.
Drop latch: A simple gravity latch where a pivoting bar drops into a slot to hold the gate closed. The cheapest and oldest gate latch design.
Dynabolt (sleeve anchor): A mechanical anchor with a sleeve that expands against the wall of a drilled hole as the bolt is tightened. Quick to install but lower capacity than chemical anchors.

E

Elevation view: A view looking horizontally at one face of the object. Front, back, left, and right elevations are the standard set, plus the top is often called the plan.
End stop: A steel block fixed to a sliding gate's track or rail. It stops the gate at the end of its travel, both when fully open and when fully shut.
Equal angle (EA / angle iron): A steel L-section with both legs the same width. Sized as leg x leg x thickness (e.g. 50x50x5 mm). Used for brackets, ledgers, and stiffeners.
Extension line: A line drawn perpendicular to the feature being dimensioned, extending outward to where the dimension line is placed.

F

Fence panel: A pre-fabricated infill panel that sits between two posts in a fencing run. Built as a rectangular frame with battens, slats, or louvres face-fixed to it, then bolted or welded to posts on site.
Fillet weld: A triangular-cross-section weld joining two surfaces meeting at an angle. Typical for hinge plates, brackets, and stiffeners.
Flat bar: A solid rectangular cross-section steel bar, sized as width x thickness (e.g. 50x6 mm). Used for hinge plates, brackets, and traditional pickets.
Footing: The concrete base into which a gate post is set. Sized by post depth and diameter to handle the post's overturning moment and hinge load.
Footplate post: A gate post bolted to a steel base plate that's anchored to a concrete pad. Used when digging a footing isn't an option.
Form 16 (engineering certification): The Queensland building approval form on which an RPEQ (Registered Professional Engineer of Queensland) certifies design or construction compliance.

G

Galvanised steel: Steel coated with a layer of zinc to resist rust. Hot-dip galvanising gives 25+ years of outdoor service in most Australian climates.
Gate motor (operator): An electric motor that opens and closes a gate for you. There are types for sliding gates, swing gates, and ones hidden underground.
Gate stop: A small steel block or angle fixed to the ground or post that physically stops the gate at its open or closed position.
Ground clearance: The gap between the bottom of a gate and the ground. Too small and the gate catches on dirt and leaves; too big and it is easy to crawl under.

H

Heat-affected zone (HAZ): The strip of parent metal next to a weld whose microstructure has been changed by the heat of welding. Often the weakest part of the joint.
Hex bolt: A bolt with a hexagonal head, fully or partially threaded, tightened with a spanner. The universal structural fastener.
Hidden line: A dashed line on a drawing showing edges that exist on the object but are hidden from view by a closer surface. Drawn as short evenly-spaced dashes.
Hinge offset: The horizontal distance from the gate-stile face to the centre of the hinge pin. Sets where the gate pivots and how much swing clearance you need.
Hinge stile: The vertical gate member on the hinge side. Carries all the gate's weight in shear and the wind moment in bending. The most heavily loaded part of the frame.
Hot-dip galvanising: Dipping fabricated steel into molten zinc at ~450 °C, forming a metallurgically-bonded zinc coating 60–100 μm thick.
Hydraulic gate closer: A piston-style closer with adjustable damping that returns a heavy gate softly to closed. Used where self-closing hinges aren't strong enough.

I

Isometric view: A 3D drawing in which all three principal axes are equally foreshortened, conveying depth without perspective distortion.

J

Juliet balcony: A balustrade fixed to the outside face of a building above a window or door, providing the look of a balcony without a deck.

K

Keypad (access controller): A weather-rated PIN-entry pad mounted near a gate that triggers the motor to open when a valid code is entered. Standard pedestrian-side gate access.

L

Latch stile: The vertical gate member on the latch side. Carries the latch hardware and stops against the catch plate or latch post when closed.
Lever-handle latch: A latch with a lever or ball handle that retracts the latch tongue when pressed. Used on pedestrian gates that need to be opened from either side.
Lock surround plate: A solid plate welded flush to the front face of a battened gate around the lockbox. It closes the gap between battens so a hand can't reach through to the lock.
Lockbox: A welded steel housing on the latch stile that holds the lock body and protects it from weather and tampering.
Loop detector: An induction loop buried in the driveway that senses metal vehicles and triggers the gate to open or hold open. Standard for vehicle-only gate operation.
Loop-top fence: A tubular fence where the top of each vertical bar bends back over the top rail in a smooth loop. No graspable top, no climb point, no spear.
Louvred gate: A gate filled with angled overlapping horizontal slats (louvres) that block the line of sight while letting airflow through.

M

Magna Latch: A magnetic, key-lockable, top-pull pool-gate latch made by D&D Technologies. The de-facto standard for AS1926.1-compliant pool gates in Australia.
Manual release: A keyed lever on a gate motor that disengages the drive so the gate can be pushed by hand. Required by AS/NZS 4505 for power-fail emergencies.
Marine-grade aluminium: Aluminium alloys (5052, 5083, 6061-T6) chosen for high corrosion resistance in saltwater environments. Used within 1 km of coast.
Mid rail: A horizontal member added between top and bottom rails for stiffness or batten anchoring. Optional on short gates, common on tall ones.
MIG welding (GMAW): Gas Metal Arc Welding. A continuous wire electrode feeds through a gun, melts in an inert gas shield, and lays a fast clean weld bead. The default for steel gate fabrication.
Mild steel: Plain low-carbon structural steel, the default material for gate frames and posts. Cheap, weldable, but rusts without coating.
Mitre joint: A joint between two members cut at matching angles (typically 45°) so they meet at a 90° corner with no exposed end-grain.

N

NCC / BCA (National Construction Code): The Australian regulatory document that sets minimum building requirements. Volume 1 covers Class 2 to 9 buildings; Volume 2 covers Class 1 and 10 (residential).

O

Orthographic view: A 2D drawing showing one face of a 3D object as if projected perpendicularly onto the drawing plane (front, side, or top).
Overlap allowance: Extra width added to each side of a sliding gate so the closed gate laps over the post or fence and leaves no gap. Usually 50 to 150 mm per side.

P

Palisade Fence: A perimeter fence of vertical spear shafts welded between horizontal rails, with pointed tips at the top. Heritage security style, common on schools, substations, and commercial yards.
Parallel Flange Channel (PFC): A steel C-shaped section with flat parallel flanges. Sized by web height (e.g. PFC 100, PFC 150). Used as posts, beams, and heavy ledgers.
Patterned battens: A custom batten layout where width, profile, and spacing vary across the gate to make a deliberate visual rhythm.
Pedestrian gate: A single-leaf gate sized for foot traffic. Standard residential widths in Australia are 900, 1000, or 1100 mm. Heights run 1200 to 2100 mm.
Photo eye (safety beam): A pair of infrared sensors across a gate opening. Breaks the beam and the gate motor stops or reverses. Standard automated-gate safety device.
Picket fence: A fence with vertical pickets (slim flat or tubular bars) running between two horizontal rails. Open structure, classical look.
Pipe (vs tube): A round hollow section sized by nominal bore (NB) for fluid flow. Different sizing convention from tube, which is sized by outside diameter.
Plan view: A view looking straight down at the object from above. Shows the footprint and any horizontal arrangement of features.
Plate: Flat steel sheet thicker than 5 mm, supplied in standard widths and lengths. Used for footplates, hinge plates, gussets, and reinforcement.
Plug weld: A weld made by drilling a hole in one part, then filling the hole with weld metal that bonds to the part underneath. Used to fix overlapping plates.
Plumb: Vertical, true to gravity. A plumb post stands at exactly 90 degrees to a level horizontal datum. Out-of-plumb is the most common gate-install fault.
Pool fence: A barrier surrounding a private pool. In Australia, AS1926.1 mandates ≥1200 mm height, ≤100 mm gaps, and self-closing self-latching gates.
Pop rivet (blind rivet): A two-part rivet installed from one side using a pull-mandrel rivet gun. Used for sheet-metal and aluminium-on-aluminium fixings.
Powder coat: A dry paint finish that's electrostatically applied and cured under heat. Standard colour finish over galvanised steel for gates and fences in Australia.
Pre-galvanised steel: Steel that's been galvanised in coil form before being shaped. Coating is thinner than hot-dip galvanise but the steel is ready to use straight from stock.
Privacy screen: A fixed panel of battens, slats, or louvres used as a free-standing or wall-mounted screen for visual privacy.

R

Rake: Rake means the ground is not flat. It slopes up or down. For a sliding gate, the slope changes how you measure the opening and how the gate is built.
Rectangular Hollow Section (RHS): Cold-formed steel tube with a rectangular cross-section, used as gate-frame stiles and rails. Common sizes 50×25 mm to 100×50 mm.

S

Sag (gate sag): The drop of the leading edge of a swing gate over time, caused by gate weight, wind load, and any out-of-plumb in the hinge stile.
Section view: A view created by imagining a cutting plane through the part and drawing what would be exposed on the cut face. Shows internal structure that elevations can't.
Self-closing: A gate behaviour: when released from any open position, the gate returns to closed automatically without manual help. Required on pool gates by AS1926.1.
Self-closing hinge: A hinge with a built-in spring or hydraulic cartridge that pulls the gate closed automatically. Required on pool gates by AS1926.1.
Self-latching: A gate behaviour: when the gate reaches its closed position, the latch engages automatically without anyone pressing or pulling it. Required on pool gates.
Setout: Marking where the posts, gates, and panels will go on the real ground before any digging starts. The last chance to catch a measuring mistake.
Side panel: A fixed (non-opening) panel adjacent to a gate, used to fill the remainder of an opening that is wider than the gate leaf.
Side-mount post: A balustrade post bolted to the side face of a slab or beam (not the top), using a heavy bracket. Used to gain headroom or skirt the slab edge.
Single rake: A gate built for ground that slopes one way. The top stays flat and level; the bottom follows the slope. You measure one height on each side.
Single swing gate: A one-leaf swing gate. Practical up to about 3.5 m wide before the leverage on the hinges starts pulling the leading edge out of plumb.
Slatted gate: A gate filled with wide solid slats arranged tight or with a minimal gap, blocking sight lines for a privacy finish.
Sliding gate: A gate that slides sideways to open, instead of swinging out. Picked when there is no room out front for a gate to swing.
Spear (Palisade): A vertical shaft (typically 25x25x1.2 SHS) running between top and bottom rails of a palisade gate or fence panel, finished in a crimped or cast tip.
Spear Arrowhead: A cast or fabricated decorative tip welded to the top of a palisade spear shaft. Heritage style, typically 120 mm tall with a 40 mm base and an optional decorative collar.
Spear-top fence: A picket or tubular fence where each vertical bar finishes in a pointed spearhead. Standard security/anti-climb top.
Spigot-mount post (balustrade): A balustrade post fixed by inserting a spigot (a stub shaft) into a sleeve cast into the slab. Lets the post be removed without breaking concrete.
Spirit level: A hand tool with a bubble in a liquid tube that shows when something is perfectly flat (level) or upright (plumb). Used to set a level datum line.
Square: At exactly 90 degrees to a reference. A square gate frame has all four corners at right angles. Out-of-square frames don't sit right and bind on hardware.
Square bar (solid bar): A solid square-cross-section steel bar (e.g. 12x12, 16x16, 20x20 mm). Used for traditional pickets, balustrade balusters, and decorative work.
Square Hollow Section (SHS): Cold-formed steel tube with a square cross-section, used as gate posts and frames. Common sizes 25×25 mm to 100×100 mm.
Stainless steel: A steel alloy with at least 10.5% chromium for natural corrosion resistance. Used on marine, pool, and architectural gate hardware.
STEP file: Standard for the Exchange of Product Model Data (ISO 10303). A neutral 3D file format for moving CAD geometry between programs.
Stick welding (MMAW): Manual Metal Arc Welding. A flux-coated electrode burns down as it welds, with the flux producing its own gas shield. Tough, portable, no gas bottle needed.
Stile: A vertical member of a gate frame. The hinge stile carries the hinges; the latch stile carries the latch. Together with the rails they form the gate perimeter.
Stitch weld: A series of short welds with gaps between them, instead of one continuous weld. Used to control distortion and reduce weld metal on long joints.
Strap hinge (T-hinge): A long-armed hinge with a strap that bolts across the face of the gate, giving a wider lever arm and more visible structure than a butt hinge.
String line: A thin line pulled tight between two points to mark a straight edge or a level line on site. The cheapest and most trusted setting-out tool.
Swing gate: A gate that pivots on hinges to open and close. Used where there is room out front for the swing arc.

T

Tack weld: A short, light weld used to hold parts in position before laying the structural welds. Quick, cheap, removable if the alignment is wrong.
Tek screw (self-drilling screw): A self-drilling, self-tapping screw with a drill point. Bites straight into steel up to about 5 mm thick without a pilot hole.
Telescopic gate: A multi-section sliding gate where panels slide and overlap, allowing a long gate to fit a runout shorter than the opening width.
TIG welding (GTAW): Gas Tungsten Arc Welding. A non-consumable tungsten electrode strikes an arc, optionally with a separate filler rod. Slow, beautiful, used on stainless and detail welds.
Title block: The bordered information block at the corner of an engineering drawing containing job name, date, scale, revision, and originator.
Top rail: The bar running across the top of a gate frame, joining the two side bars. It caps the gate and holds the tops of the battens or slats.
Top roller (guide roller): On a cantilever gate, a pair of rollers fixed to the post. They hold up the cantilever rail and let the gate slide, and they carry the gate's weight.
Tubular fence: A fence built from steel tubes (square or round), welded into panels with vertical infill bars between top and bottom rails.

U

U-track: A steel channel set into the ground with the open side up. The gate's wheels run inside it. Another option instead of V-track for a tracked sliding gate.
Unequal angle (UA): A steel L-section with the two legs different widths. Sized as long-leg x short-leg x thickness (e.g. 75x50x6 mm).

V

V-track: A steel rail with a V-shaped top, set into the ground. The gate's grooved wheels sit in the V and roll along it. The common track for a tracked sliding gate.

W

Wall-bolted post: A gate post bolted to an existing brick, block, or concrete wall. Used where a hinge stile lands on a building face.
Weld penetration: How deeply weld metal fuses into the parent metal. Full penetration develops the full strength of the joint; partial penetration is sized to the load.
Weld throat thickness: The shortest distance from the root of a fillet weld to its theoretical face. Determines the shear capacity of the weld.
Weld-on hinge: A hinge with a steel barrel that gets welded directly to the gate stile and post, no bolts or plates. Standard for medium and heavy steel gates.
Welded mesh fence: A fence panel made from horizontal and vertical wires welded into a rigid grid. Common for security, schools, and animal enclosures.
Wicket gate: A small pedestrian gate built into a larger driveway gate, letting one person walk through without opening the full gate.
Wrought iron: A traditional ferrous material with a fibrous internal structure, hand-forged into decorative gates and railings. Mostly replaced by mild steel today.

Z

Zincalume: A BlueScope Steel coating of 55% aluminium and 45% zinc on mild-steel sheet. Lasts longer than plain galvanise in most environments.