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Book:	Fencing
Chapter:	5 Techniques for post and wire fencing
Section:	Handling, straining, fixing and joining wire
Metadata:	Details	Buy this book

Always treat wire with respect, both to prevent damage to the wire, and to ensure there is no risk to the handler or any bystanders. High tensile wire requires particular care, as its springiness makes it liable to tangle in the coil if not handled with care.

Handling plain wire

Plain wire is normally supplied in 25 or 5kg coils. Weight/length equivalents are given on page 35. The start of a new coil should be marked with a label. Mark the start end of a partly used coil with a U bend, and bind the coil at three points with tying wire.

Mild steel wire can be unwound by attaching the start end at the straining post, and then unrolling the coil along the ground. This is satisfactory on level grassland, but difficult in rough terrain. Use of a wire dispenser (see safety, equipment and organisation) is safer and more efficient, and is essential for handling high tensile or spring steel wire. Place the coil on the dispenser with the start end down, so the wire feeds off from the bottom of the coil. Do not undo the tying wires until the coil is clamped in position.

Always secure high tensile or spring steel wire on both sides of the cut before cutting, to prevent the wire recoiling. The method used will depend on the straining procedure. If possible, strain and fasten the wire before it is cut. Alternatively, put your foot on the wire to hold, or get another person to help. After cutting, push the free end of the coil into the ground to temporarily secure it, or bend the free end to mark it and replace on the coil.

Tensioning devices such as Gripples are threaded onto the wire, which therefore has to be cut before it is strained. Spiral fence connectorsÂ can be wound onto the wire before it is cut.

The sequence of operations will depend on the situation, but a suggested method is as follows:

Put the dispenser at the second straining post from the start of the fence, pull out the wire to the first straining post and fasten off.
Attach the wire strainers to the second straining post. Strain and cut the wire, the order depending on the method of attachment. On uneven ground, the wire is left on the strainers to allow for adjustment in wire tension (see constructing). Otherwise fasten off. Repeat stage 1 and 2 for each line wire required.
Without moving the dispenser, pull the wire out to the third straining post, fasten off and strain back to the second straining post and fasten off as before. Repeat as necessary.
Move the dispenser, strainers and other tools to the fourth straining post, and strain to the third and fifth posts. This procedure saves moving the dispenser and other tools more than necessary.

Handling barbed wire

Always wear thick gloves, preferably of leather, with gauntlets to protect the wrists.
Take care when transporting reels of barbed wire inside vehicles. Place the reels inside tool boxes or separate compartments.
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To unroll barbed wire, slide a short crowbar or stout piece of wood through the reel, so it can be safely carried by two people. Place the reel so the wire feeds off the bottom.
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Always put up any barbed wire as the last job, to avoid the chance of people damaging themselves on it while the fence is being erected.

Handling stock netting

On short grassland and fairly level ground, netting can be unrolled by laying the roll on the ground, and then walking backwards along the fence line, unrolling the netting as you go. Don't stick your fingers down between the wires, because every so often the middle part of the roll suddenly unwinds, and can trap the fingers. Use the heel of the hand, and don't let go towards the end or the whole lot will roll back up again!
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On difficult ground you will have to keep the roll of netting upright, lifting and turning it to unroll the netting.

Straining wire

Many different methods have been devised for straining wire, some of which are described below. The Monkey strainer (or similar type) is the most widely used and versatile tool for straining wire. Note the following general points:

When using the wire strainer, always make sure before you start operating the lever, that the grips are securely holding the wire and that the chain is not twisted. If the chain is twisted, it will jam as the strain is taken up.
Pull the wire reasonably taut by hand before you attach it to the grip, or you will run out of chain before the wire is fully tensioned, and then have to release the strainers from the wire and start again. This is especially important on long strains. As the total length of strain increases, so does the amount of 'stretch' that you need to take up with the strainers.
It requires some practice and dexterity to attach wire strainers quickly and efficiently, particularly on awkwardly placed wire such as the bottom wire on a roll of stock netting. It is more easily done with someone else to help, either holding the wire or netting in position, or forcing the wire down into the grip of the strainers.
Once the strainer is attached, one person should easily be able to operate it. Never add a longer handle to give extra leverage, as the strainers are designed to allow a person of average strength to put sufficient tension on the wire.
It is advisable for other people to stand out of the way while the wire is being strained, in case the wire slips and springs back, or breaks.

Normal straining

The strainers are attached as shown, with the chain looped around the post. Make sure that the chain is just out of the way of the line of the wire. If it's on the same line, it will be in the way when you come to fasten the wire. If it's too far above or below, it will be pulling the wire out of line.

Loop the chain as shown, so that it runs out on the same side of the post as the wire, to keep the line of strain straight.

The last short section between the wire strainer and the straining post can be tensioned with a Gripple Tensioning Tool, and fastened off with a Gripple. This must be threaded on the wire before it is passed around the straining post (see below).

Alternatively use fencing pliers or a Myti wire strainer. It's easier if one person pulls the wire around the post with strainer or pliers, while another person fastens it by one of the recommended methods. To allow for the small overall loss of tension resulting from doing this, slightly more tension can be put on the Monkey strainers to compensate. This shouldn't need to be as much as one link in the chain, but it should be sufficient if the operator of the strainers can hold the lever at the 'half-way' stage for a few moments while the wire is fastened off. This may seem rather a fine point to worry about, but especially on strains less than 50m, the difference can be significant.

A variation of this method is to use a wire strop, attached as shown to the straining post. The advantage is that it keeps the chain well away from the straining post, so that it does not interfere with the operation of fastening the wire to the post. It also allows the full length of chain to be used, so that a longer length of wire can be strained.

To strain netting, two sets of Monkey strainers can be used as shown, or for better results use a clamp with strainers. The last section is strained by hand using a Myti strainer or fencing pliers, and the wires attached to the post with staples, or back on themselves with spiral connnectors. The Gripple system, which is useful for joining netting, can't easily be used to strain and fasten off netting, because the vertical wires prevent the Gripple being slid along the horizontal wires.

Back-straining

This method avoids having to strain the last section by hand, and is suitable for straining plain wire.

The strainers are attached as shown below, with the wire passed around the post. Make sure the wire is at the correct height around the post, because it will not be possible to slide it up or down once the strain is on it. Loosely tack a guide staple. Strain the wire to the required tension, and then secure it back on itself using a spiral fence connector or a Gripple (which must be threaded on before the wire is passed around the post). Do not secure the wire by driving home the guide staple, as in order to hold the wire under tension, you will have to hit the staple so far in that it will damage the galvanising of the wire.

Back-straining is the best method for straining plain wire around a round straining post. It is less easy with a square straining post, as the wire digs into the corners of the post as it is pulled around. Straining barbed wire or stock netting by this method is not recommended, as the barbs and joins catch on the post as the strain is taken up.

To strain up to 200m length of plain wire by this method, the Gripple tensioning tool and Gripple can be used instead of Monkey strainers.

Fixed object

In order to avoid the problem of straining the last piece by hand, it is possible to attach the strainers to a convenient object such as a tree, or a stationary vehicle. However, this method is not recommended, for the following reasons.

The straining post must be allowed to take up the strain gradually as tension is put on the wire. If you strain to another object, fasten off to the straining post and then release the strainers, the tension is suddenly transferred to the straining post, which is much more likely to move and possibly pull out of the ground.
With the strainers in the position shown, there is no satisfactory way of securely fastening the wire to the straining post so that the wire does not slip when the strainers are removed. The only way is to knock in staples so far that the wire is kinked and the galvanising damaged.

Other methods of straining allow either the wire to be taken around the post and joined back on itself with a connector, or allow the free end to be bent into a gentle 'U', giving increased friction between wire, post and staple. Don't be tempted to try and use a stationary object placed at an angle to the straining post in order to give a longer length of contact between the wire and the post. Strainers so placed will then be pulling the straining post in a direction which it is not designed to withstand.

Extra post

Some fencers favour using an extra post or other device, temporarily braced against the straining post, in order to avoid straining the last piece by hand. However this has the same disadvantage as described above in attaching the wire, although it does allow the straining post to take up the strain gradually. It must be positioned directly in line with the fence, or it will twist as the strain is taken up.

Various home-made metal devices are also used, notably at fencing competitions at agricultural shows, where speed is important and the durability of the wire attachment is not. An example is shown below.

Straining clamps or boards

These are used for straining stock netting. Clamps are available commercially, or can be home-made (see safety, equipment and organisation). Drivall supply 110cm clamps for standard netting, and 220cm clamps for deer netting. Clamps are used with Monkey wire strainers and strops, or with Drivall boundary fence strainers, which have hooks instead of grips, for easy attachment to the clamp, and 6m of chain to increase the length of netting which can be strained.

There are two main methods of using clamps:

1 One method is to attach a pair of clamps to the straining post, using strops and standard strainers or the boundary fence strainers described above. This can be done in either of the ways shown. The last section of netting must be strained as described above. Drivall boundary fence strainers have a 6m chain, which allows up to 400m of high tensile netting to be strained in one go. Monkey strainers have 1.5m of chain, which means that only 100m of high tensile netting can be strained at a time. High tensile netting stretches 1.5m in every 100m, so if you try to strain a longer length of netting you will run out of chain before the netting is fully strained.
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2 Another method of using straining clamps is to attach two pairs of clamps to join the ends of two lengths of netting part way between straining posts. This avoids doing any straining by hand, as the ends are attached to the straining posts before straining, and a very even tension can be achieved along the whole length. Join the netting with fence connectors, Gripples or other joining devices.
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Table 5a GALVANISED STAPLES approximate weights and quantities

Metric Imperial Approx.
>(mm) (inch x SWG) no per kg Use

15 x 1.60 0.50 x 16 2060 Wire netting, light welded mesh

20 x 2.00 0.75 x 14 931 Chestnut paling

25 x 2.65 1 x 12 488 Chain link, heavy welded mesh

25 x 3.15 1 x 10 358 Chain link, heavy welded mesh

30 x 3.55 1.25 x 9 221 Plain wire

40 x 4.00 1.5 x 8 134 Barbed wire

50 x 5.00 2.0 x 6 73 Strand wire
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Pairs of clamps can be used on mild steel netting, but because of the shorter lengths involved, there is less benefit to be gained.

Joining, fastening & tensioning wire

In recent years there have been several devices developed for joining wire. If these are used to fasten the wire back on itself at straining posts, they also serve to secure the wire to the post, without the need for using staples. Devices such as radisseurs and Gripples join wire and can also be re-tensioned at any time. These devices add to the cost of the fence, but are more efficient than knotting or stapling as ways of joining and fastening wire, as well as having the benefit of being re-tensionable.

Stapling

Staples are the traditional method of fixing wire to straining posts and intermediate posts. Staples are easy to use, and are available everywhere. They are still the best method to use on intermediate posts, but there are disadvantages to their use on straining posts.

On intermediate stakes, staples are always fastened to a 'running fit'. This means they are knocked in far enough to hold the wire against the post, but not so far as to grip the wire. This allows an even tension to be made between the two straining posts. The wire can also later be tightened as necessary, without having to loosen the staples on the intermediates. Any extra strain imposed on the wire by a weight leaning against it is taken up along the whole length of the wire. The intermediates are in effect only stiffening the fence, and holding the horizontal wires at the correct distance apart.

Don't leave a large gap between staples and wire, or the wire will rattle in the wind and the galvanising will be damaged. Staples should always be angled as shown. If the staple is aligned vertically with both points entering the same grain, the wood is likely to split. When stapling netting or barbed wire onto intermediates before the wire is fully strained, ensure the staple is so placed that it will allow the wire to be tightened.

Use two staples on dips or rises, to reduce the kink of the wire, and increase holding strength. This also allows the wire to feed through more easily.

On turning posts staples should be knocked to a running fit, but in order to prevent the wire cutting into the post, place an extra staple as shown.

In addition to the normal plain staples, barbed staples are available which are designed for use on softwood posts (Tornado, Jacksons Fencing). If the post dries out and splits, the barb prevents the staple from pulling out. Green Rylock staples are available for use with Green Rylock wire products (Sentinel Fencing).

If staples are used to fasten off wire at straining posts, the staples have to be knocked in so that they securely grip the wire. This should not be done by knocking the staples in so far that they kink the wire and damage the galvanising. It should instead be done by sharply angling the staple so that it pinches the wire. In order to make a secure fixing, the wire must be bent into a 'U' curve. Avoid making a sharp 'V'. Use either of the following methods, on mild steel wire and mild steel barbed wire only. High tensile or spring steel wire should not be fastened off with staples, but with one of the devices listed below.

However, even these methods shown have some disadvantages. The bending inevitably causes some damage to the wire galvanising, and on stock netting or multi-strand wire fencing the number of staples used can be considerable. For example, a straining post part way along a run of eight strand stock netting with a top and bottom strand of plain wire might have over 40 staples knocked into it. Staples can also work loose in time, from frost causing expansion and contraction of the wood. For these reasons, the other methods described below are recommended instead of stapling at straining posts.

Gripple

This is a device for joining, fastening and tensioning wire. The wires feed in from opposite ends and are gripped tight by toothed roller bearings. The greater the force exerted to pull the wires back, the tighter the device grips the wires. Four sizes of Gripple are manufactured, suitable for most types and sizes of wire including mild steel and high tensile plain and barbed wires, and stock netting. They can be removed and re-used.

To join plain wire, barbed wire or stock netting which are not under tension, the wires are fed into the Gripple from opposite sides as shown.

To fasten off the start end of a length of plain wire, the Gripple must be slid onto the wire before it is passed around the fence. The end of the wire is then fed through to secure.

This method cannot be used for stock netting or barbed wire, as the Gripple cannot be slid along netting or barbed wire. For the same reason, the Gripple can be used to tension a length of plain wire, but not barbed wire or netting. To tension up to 200m of plain wire:

1 Pull the wire as tight as possible by hand.
2 Cut the wire allowing sufficient to pass around the post and fasten off, keeping hold of the free end.
3 Thread on the Gripple.
4 Pass the wire around the post and thread it back through the Gripple.
5 Use the Gripple Tensioning Tool to tighten the wire.
6 Cut off to leave at least 50mm (2") free end
to allow for re-tensioning in the future.
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The following sizes of Gripple are available:

To tension barbed wire, attach it to a length of plain wire using a Gripple. Then use the length of plain wire to take up the strain as shown, and secure with a second Gripple.

Gripples can be used to join lengths of stock netting which are strained to the middle with clamps and strainers. Using the Gripple Tensioning Tool, minor re-tensioning adjustments can be made to barbed wire and netting, but only so far as the Gripple can be moved along the wire between barbs or verticals. SeeÂ constructing for their use in mending fences.

Gripples are manufactured by Gripple Ltd and marketed by Estate Wire Ltd. The same device is marketed by Sentinel Fencing and is known as a Rapido. Triple Life stock netting from Estate Wire Ltd is factory fitted with Gripples on each horizontal at the start end of the roll.

Spiral connectors

These are used for joining wires and for fastening off at straining posts.

The spiral design was originally developed for use in the telecommunications industry. The idea was extended for use on strained wire structures for hop, vine and fruit growing, as well as for fencing. For cost effectiveness they are best used on high tensile wires, which also should not need re-tensioning. Spiral connectors can be taken off and re-used, for example on mild steel wires that need re-tensioning. Spiral connectors are easy to fit by hand and no tools are required. Two sizes are available, for use on 2.64mm (12 gauge) or 3.25mm (10 gauge) wire.

Connectors are attached as follows:

To fix a wire that is not under strain, pass the wire around the post, locating it at the back with a staple.
Allow at least 500mm from the start of the wire to the post. With the centre mark on the connector level with the end of the wire, wrap that half around the wire, starting from the centre point.
Then wrap the other half of the connector around the wire, checking that the end of the connector is snapped into place.
Strain as normal to the next straining post using the back-straining method. Leave enough tail end of the wire free for attaching the connector. Strain to the required tension, and then attach the connector as described above.

Some fencers like to leave a tail of wire protruding to make it easier to remove the connector if re-tensioning is necessary. The tail of wire can then be 'unwound', rather than trying to prise the connector free and unwind it off the wire.

However, this is not generally recommended, as it makes the connector easier to vandalise, and also leaves the temptation to undo the wire while it is under tension, which is dangerous.
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Spiral connectors are a neat and strong method of joining wires. Two units are required to form the join or splice. They can be taken off and re-used, but cannot be re-tensioned in position.

Starting with the centre mark of one unit level with the end of the wire, wrap half the connector around the wire.
Then wrap the other half of the connector around the wire to be joined.
Repeat with the second unit, winding it into the spaces in the first unit. Ensure all ends are snapped into place.

Crimps

Four different sizes of crimp sleeves are available to join plain wire, barbed wire, stock netting and electric fence wire. They are fastened using the Ezecrimp tool (see safety, equipment and organisation). They cannot be re-tensioned or reused.

Twisting

This method of fastening should only be used on mild steel wire. It is not suitable for high tensile wire, which will spring undone. The neatest finish is achieved by using a small tool called a wire twister (see safety, equipment and organisation).

This method is useful on mild steel stock netting, where many staples would otherwise be needed, and the cost of wire connectors may not be justified. A disadvantage is that the twisted wire is difficult to re-attach if the fence has to be restrained.

Twisting can also be used to join lengths of mild steel stock netting. However, spiral connectors, crimps or Gripples are stronger and neater.

Radisseur

The radisseur, butterfly tightener or in-line strainer is a galvanised steel device used on mild steel and high tensile line wires. Radisseurs are not suitable for stock netting or barbed wire.

The radisseur can be used to adjust tension at any time, both while the fence is being erected, or if the wires subsequently lose tension due to temperature change or movement of posts. Mild steel wire, however well tensioned initially, normally requires re-tensioning after a few months.

Radisseurs can be a bit tricky to fit, as it is awkward to start the winding action when the wire is not under tension. You need to pull the wire fairly tight before you start fitting the radisseur, or you will run out of space on the reel. A spanner is needed to tighten it, or use a special tightening handle, available from Drivall, which makes the job easier.

Radisseurs can be fitted in a number of different ways, as shown. A loop with spiral connector gives the strongest and neatest fit.

Wire tightener

Clip to new wires or those that have gone slack, and wind with special handle to tighten (Drivall, BTCV).

Ratchet winder

This is similar in principle to the radisseur, but is a stronger device with a larger reel capacity. It requires drilling a hole through the post.

Eyebolts

These are mainly used on concrete or metal posts. They can also be used on wooden posts, but have a tendency to pull through with time, especially on softwood posts which have been drilled after preservative treatment. Common sizes are 10mm diameter and 200, 260 and 300mm length.

As the eyebolt has a relatively small adjustment, the wire must be almost fully tensioned using wire strainers. The wire is attached by knotting or twisting it through the eye, and the wire strained to full tension by tightening the nut and washer. Further adjustments to the wire tension can be made as necessary. Loop adaptors can be used to make a double-ended eyebolt for use at straining posts part way along fence lines.

Knotting to attach

As used above for eyebolts and radisseurs, and to attach strain insulators in electric fencing (see electric fencing).

Knotting to join

Knots to join wires have been superseded by the use of devices listed above. Knots are awkward to make neatly, have a tendency to slip and should not be used on high tensile or spring steel wire.

Joining netting to line wires

One fencing technique is to suspend a netting fence on line wires of high tensile spring steel (see designs 4, 7and 8 in chapter 1). The netting is only lightly strained, and the tension is kept in the fence by the line wires.

The netting can be joined to the line wires either by rings or lashing rods. Wire rings are applied using a ring fastener gun, which is quick and easy to use. The gun closes the ring, which should stay closed unless put under strain by the weight of drifting snow or animals leaning or rubbing on the netting.

A stronger join is made by using lashing rods, which are available in two sizes:

For securing B or C grade stock netting to 2.65mm (12 gauge) line wire.
For securing B grade stock netting to 3.15mm (10 gauge) line wire, or two grade C nets to 2.65mm (12 gauge) line wire, as used for deer fencing.

Lashing rods are supplied in boxes of 500, and should be supplied neatly packed. Once tangled, they are awkward to disentangle for use. The easiest way to wind on the lashing rod is to use a short piece of wire as shown. They should be spaced at about 2m intervals. Lashing rods are not suitable for use on hexagonal mesh, as the mesh is too small to attach them. Available from Tornado (see suppliers).