Fixed Knot Fencing: How to Clip It and What It Costs
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Fixed knot mesh carries its own tension, so you don't clip it the same way you clip hinged joint. Most of your clips go into roll joins, aprons and top wires rather than into every line wire at every post. Budget on the materials for a tall exclusion grade fixed knot run costing several thousand dollars a kilometre before labour, and expect an all up figure into five figures per kilometre once you add posts, strainers, an apron and someone's time.
That's the short version. Below is what the knot actually does, why it changes the clipping, and how to work out your own numbers instead of taking a guess off a forum.
What the fixed knot is doing
A hinge joint knot is a wrap. It's made to move and spring back after a hit. A fixed knot is a separate piece of wire tied around the line wire and the vertical stay so the joint doesn't slide either way.
That one difference changes the whole fence.
Because the knot won't slip, the mesh holds its own geometry under tension. You can strain a fixed knot fence up hard and the wire spacings stay where the factory put them. High tensile line wire in the mesh means it takes and holds that tension rather than stretching out over a couple of summers.
You'll see it written as codes like 13/190/15, 16/180/15 and 17/190/15. Same convention as hinged joint. First number is line wires, second is height in centimetres, third is stay spacing in centimetres. So 17/190/15 is 17 line wires, 1.9 metres tall, stays every 150mm. Australian product is generally manufactured to AS 2423 with zinc coating to AS/NZS 4534.
Why that changes where you clip
On hinged joint you're effectively hanging soft mesh off strained plain wires, so you clip a lot and you clip often. Have a read of how to clip hinged joint mesh if that's the job in front of you.
Fixed knot is a different animal. The mesh is the structure. Over constraining it at every line wire at every post can work against you, because a high tensile fence wants to move slightly along its length as it heats, cools and takes a knock. Pin every wire at every post and that movement has nowhere to go.
So the common approach on a fixed knot run looks like this.
- Strain the mesh itself, properly, with a spreader bar across the full face of the roll.
- Fix at the posts with staples on timber (driven at an angle, not flush, so the wire can still move) or with post clips on steel.
- Use C24 rings for the work the staples and post clips can't do.
That last line is where a clip gun earns its keep on this sort of fence.
The four jobs a clip does on a fixed knot fence
Roll joins. Where two rolls meet you overlap and tie the line wires together. Clipping through the overlap at every line wire makes a join that carries load evenly instead of hanging off two or three tied wires.
Aprons and skirts. If there's an apron laid out on the ground or turned down and pegged, it gets clipped to the bottom of the main mesh, usually every 300mm or so along the whole run. On a kilometre that's a lot of clips and it's the single biggest clip consumer on an exclusion job.
Top and bottom plain wires. A plain wire above the mesh, a barb on top, or a plain wire along the bottom all get clipped back to the mesh so nothing can be lifted or pushed through the gap.
Repairs and add ons. Patching a hole, adding a lower skirt to an existing fence, splicing in a new panel after a tree comes down. The gun does in a few seconds what pliers do in a minute and a bit.
Working out your clip count
The calculation is the same one we use everywhere. Count what you're actually clipping, not what's theoretically clippable.
| What you're clipping | Working | Clips per km |
|---|---|---|
| Apron to mesh at 300mm | 1000 / 0.3 | 3,334 |
| Apron to mesh at 500mm | 1000 / 0.5 | 2,000 |
| Top plain wire at 500mm | 1000 / 0.5 | 2,000 |
| Bottom plain wire at 500mm | 1000 / 0.5 | 2,000 |
| Roll joins, 17 wires, rolls every 100m | 17 x 10 | 170 |
| Every line wire at every post, 13 wires, 4m posts | 13 x 250 | 3,250 |
That last row is the upper bound rather than the expected number. Most fixed knot jobs don't clip every wire at every post, for the reason above. If your fence design does call for it, check the mesh manufacturer's installation guide first, because some of them are specific about it and some of them are specific about not doing it.
A realistic exclusion grade fixed knot run with an apron clipped at 300mm plus a top and bottom plain wire lands somewhere around 7,000 clips a kilometre. A box of 10,000 won't quite do a kilometre and a half of that. Compare that to a standard hinged joint run at two to three thousand and you can see why people underorder.
The clip calculator will run your own numbers off your mesh code, post spacing and apron spacing, and there's more working shown in how many clips per kilometre of fence.
What a fixed knot run costs
Anyone who gives you a single number for this is guessing. Costs move with terrain, clearing, post type, mesh height and who's doing the labour. But here's how to build your own estimate.
| Line item | What drives it |
|---|---|
| Mesh | Height and line wire count. A 1.9m 17 wire roll costs a lot more per metre than a 0.9m 8 wire roll. |
| Posts and droppers | Spacing, and whether you're on steel, timber or a mix. |
| Strainers and stays | Every corner, every change of direction, every gateway. |
| Plain wire and barb | Top wire, bottom wire, any barbs. |
| Clips and staples | Use the table above, then add 10 per cent. |
| Apron | Extra mesh, pegs, and the clips to hang it. |
| Clearing and preparation | The line item that blows out on scrubby country. |
| Labour | Contract rate per kilometre or your own time at a rate you're honest about. |
For reference points that are published rather than invented: an often quoted Australian figure for a tall fixed knot kangaroo exclusion fence puts materials in the region of $5,500 a kilometre and labour and clearing at around $5,000 a kilometre, though that example dates from 2019 and materials have moved since. A separate indicative figure for a full exclusion fence that stops deer, macropods, pigs and wild dogs, apron included, sits around $16,000 a kilometre. Treat both as a sense check for your own quotes, not as a price.
What that tells you is useful all the same. Clips are a small fraction of the total on a fixed knot job. Skimping on the clip to save a few hundred dollars across a fence that costs five figures a kilometre is a false economy, especially with the coating. See stainless vs galvanised fencing clips for where that call actually matters.
Practical notes from the fence line
Tension in stages. Bring a fixed knot roll up gradually and walk it, rather than winching it hard in one go. The knot won't let the mesh redistribute for you.
Watch your ground line. A fixed knot fence is only as good as its bottom. Any dip you don't pull the mesh into is a gap, and on exclusion work a gap is the whole ballgame. Aprons exist for this reason.
Keep the closure consistent. A C24 ring on high tensile mesh wants to be closed snug without flattening the wire. Set the gun on a scrap first and leave it alone.
Order the clips with the mesh. There's nothing more annoying than a roll of mesh sitting on the ground waiting for a box of rings to turn up.
The tool side of it
A cordless gun suits fixed knot work because the job is usually a long way from a power point. No compressor, and no hose to drag along behind you.
The Outback ClipGun kit runs a 4.0Ah battery with a 240V charger, holds 120 rings in the magazine and weighs 2.75kg without the battery. It fires standard C24 clips, so you're buying an industry size rather than something proprietary. The rest of the range is on the fencing clip guns collection.
If the fence you're planning is exclusion grade, read the exclusion fencing clipping guide before you order anything, because the apron changes your clip count more than anything else does.
FAQ
Is fixed knot better than hinged joint?
It's different rather than better. Fixed knot holds its shape under tension and suits tall exclusion work and hard country. Hinged joint flexes and springs back, costs less, and it's still the right call for most internal stock fencing.
Do I clip fixed knot at every post?
Usually not every line wire at every post. The mesh carries its own tension, so it's normally fixed with staples or post clips and the C24 rings go into joins, aprons and plain wires. Follow the mesh manufacturer's installation guide, because they vary.
What clip size does fixed knot mesh take?
C24 rings, same as hinged joint. 16 gauge, 1.8mm wire, 24mm crown. Set the closure so the ring grips without flattening the high tensile wire.
How many clips for a kilometre of exclusion grade fixed knot?
With an apron clipped at 300mm plus a top and bottom plain wire, around 7,000 per kilometre. Without an apron it drops a long way. Run your own figures through the clip calculator.
Can I use a clip gun on high tensile mesh?
Yes, that's what C24 rings are for. The thing to get right is the closure setting, because over closing on high tensile wire cracks the coating and that's where the rust takes hold.
What does a fixed knot fence cost per kilometre?
There's no single answer. Published Australian reference points put a tall exclusion grade fence somewhere around five figures a kilometre once you include posts, clearing, an apron and labour. Price your own mesh, posts and labour and use the table above as the checklist.