In undulating ground, straining posts should be sited in the bottom of dips, in order to anchor the fence securely. However, this is not always possible, and it may be necessary to anchor intermediate stakes in dips using tie downs, to prevent them pulling up when the wire is strained. The same technique can be used in soft ground, where it is impossible to get stakes firm simply by knocking them in.
Tie downs can also be used on high tensile wires and netting, to pull the fence down at dips that occur between stakes, which may be spaced up to 10m apart. However, these do not always hold firm, and it is better to fill in with earth or rails where possible.
Some different methods of making tie downs are shown below. The greater the angle the wire is pulled down, the stronger must be the attachment of the tie-down in the ground.
Spanish windlass
This can be used to firm up stakes in mild steel fencing, where they cross soft ground.
- Knock two fencing stakes as shown, as far as possible into the ground, but leaving at least 150mm protruding.
- Run a length of 4.00mm mild steel wire as shown, and staple. Repeat for the other side.
- Then with one person each side, insert a stout piece of wood or wrecking bar between the wires and twist until tight. The wood or bar can then be removed.
- Cut off the stake tops if protruding over about 150mm.
Ground anchor
This is a special metal disc with a wire threaded through, which is screwed down into the ground using a T shaped handle. Ground anchors are very strong, but have the disadvantage that if the disc hits a rock before it goes deep enough, it cannot easily be retrieved. Ground anchors and handle are available from Gallagher Power Fence (UK) Ltd.
Gripple Ltd supply the Anchor Fast system, which includes a ‘duckbill’ ground anchor that is inserted into the ground with a special tool. This is attached to the post with a wire rope that is tensioned with a Gripple rope grip.
Buried object
Sometimes it is possible to use a large log, rock or even a piece of scrap machinery to anchor a high tensile fence in a dip. Attach a wire to a dropper and fasten it around the object. Fill in to hide the object as necessary, and to make the fence stock proof.
