What are Fence and Gate Fittings?

Fittings are the connectors and hardware that join a fence together: the caps, brackets, clamps, hinges, latches and bolts that turn lengths of pipe and rolls of mesh into a working fence line with a gate that opens.

They are also where most fence failures start. A fence with the right posts and the wrong hinges will sag; a correctly built gate with an under-specified latch will be the thing that gets forced. Getting fittings right is cheap insurance relative to the cost of the rest of the job.

Understanding nominal bore (NB)

This is the single most important thing to get right when ordering fittings.

Fitting sizes are quoted in nominal bore (NB), not outside diameter (OD). NB is a legacy sizing convention that approximates the internal bore of a pipe — it is not the measurement you get by putting a tape across the outside of your post.

If you measure your existing post, you have measured the OD. You then need an NB-to-OD conversion table to work out which fitting will fit. Ordering by measured OD as though it were NB is the most common fitting ordering error.

Always confirm OD measurements before ordering, and convert to NB using a reference table.

Common fence and gate fittings

Post caps and domes — for square and round posts. Keep water out of the post, which is what determines how long the post lasts from the inside
Gate hinges — adjustable, butt and gudgeon types
Gudgeons — the pin half of a traditional gate hinge, fixed to the post
Rail brackets and cradles — carry the top and mid rails
Collars and clamps — fix mid-rails and stays to posts
Tees, corners and crosses — fixed pipe connectors for framing
Flanges and base plates — for surface-mounting posts to concrete
Drop bolts, latch kits and padlockable hardware
Chain and cable anchors
Temporary fence clamps — joining temporary panels
Fence panel U-clips

Finishes

Fittings are generally supplied in a hot-dip galvanised finish as standard. Select items are also available powder coated — usually black — so they disappear against a coated fence rather than standing out as bright galvanised spots along the line.

Otter stocks fittings from Downee and Vater, available individually or in box lots.

Installation notes and tips

Use anti-seize on adjustable or threaded fittings in coastal or exposed environments. Threads that seize are threads you cannot adjust later, and gate hinges need adjusting
Space and align gate hinges correctly — most gate sag traces back to hinge placement rather than gate construction. Get the vertical spread as wide as the frame allows
Welded fittings offer additional security but reduce post reusability. Worth it on a security line; not worth it on a fence you may reconfigure
Spring latches and buffer stops are recommended on gates with frequent pedestrian use — they take the shock out of the closing cycle
Paint or powder coat visible fittings to match the fence colour and reduce visual clutter
For uncommon sizes, fittings can often be fabricated or adapted using welding or bush sleeves rather than redesigning the fence around available stock

Optional accessories and tools

Rattle-proof collars for rail sections — worth it near residences and on windy sites
Security shear nuts or tamper-proof fasteners — the nut head shears off on installation, leaving nothing to grip
Gate stop brackets and restrainers — stop the gate over-travelling and tearing hinges
Grease points on gate hinges in high-usage applications

Matching fittings to fence type

Fittings differ across systems — a chain-link fitting will not suit a tubular post, because the post sections are different shapes.

Chain-link — round pipe posts and rails, so fittings are sized in NB and clamp around round sections
Tubular — square posts, so brackets are flat-faced and screw-fixed, in standard or tamper-resistant versions
Welded mesh — square posts with panel clamps or U-clips sized to the panel wire
Temporary fencing — dedicated clamps that join adjacent panel frames
Gate automation — mounting brackets appropriate to the post or pillar structure

Relevant Australian Standards

AS/NZS 4680:2006 — Hot-dip galvanized coatings on fabricated ferrous articles; covers fittings, hardware and fasteners
AS 4506-2005 — Metal finishing: thermoset powder coatings
AS/NZS 2699.1:2000 and 2699.2:2000 — Built-in components for masonry construction; relevant to wall ties, connectors and accessories used with chemical anchoring and fasteners

Common questions

What does NB mean?

Nominal bore — the sizing convention used for pipe fittings. It is not the outside diameter of the pipe. Use a conversion table to go from your measured OD to the NB size to order.

Why won't my fitting fit?

Almost always because an outside diameter measurement was ordered as though it were a nominal bore size. Measure the OD, then convert.

Can I buy fittings individually?

Yes — individually or in box lots.

Are fittings available in black?

Select fittings are available powder coated in black. The standard finish is hot-dip galvanised.

My gate is sagging. What went wrong?

Usually hinge spacing or alignment, or hinges under-rated for the gate weight. Post movement is the other common cause — gate posts need concrete footings.

What if the fitting I need isn't listed?

Non-standard fittings can often be fabricated or adapted with welding or bush sleeves. Contact Otter Fencing on (03) 8791 2000 or sales@otterfencing.com.au.