A simple device to tighten slack fences

By Johan Norval | 18 May 2017

Michris Janse van Rensburg was inspired by a design of an Australian entrepreneur that he spotted on social media. “Everyone asked me to make one like it. The Australian version cost around K800 but the man refused to sell it to us. The solution? I made my own version,” he said.

Michris designed ten prototypes of his version of a wire tensioner before he got it right. While designing the device, he kept in mind the needs of clients who often buy his tools.

The wire in the fence after it has been tightened.

“The wire tensioning device is aimed at tightening slack fences without loosening the wire at support poles and starting from scratch. You can even join two sets of wire with it.”

Janse van Rensburg improved the Australian version by joining a piece of pipe at the bottom of each handle so that one can insert another piece of pipe into it (or pliers, like Michris does) to lenghten the handles for improved leverage. This is useful, in the case of steel wire that has to be stretched more.

His device consists of two “arms” of flat iron bars of 600mm each, of which the tops are bolted onto a short “hinge bar” of around 100mm.

The pinching action of the wire is accomplished by cutting through the two lever arms at an angle, about 200mm from the top. A short strip of flat iron is used to join the two parts of the arm again by welding this flat iron to the top part of the arm, and bolting the bottom end of the arm to the flat iron strip. In this way it could hinge as well as pinch the wire by jamming it between the two parts of the arm

The wire is now tightened between the two arms. When a strip of fencing wire is caught between these two jamming points and pushed closer, a loop of wire is formed. To keep the tension, the two arms are joined with a chain at the bottom.

Michris with a South African product developed from an Australian idea.

A loose piece of wire is then fastened on both sides of the tightened fencing wire. Using a short iron strip, the wire loop can now be wound up to maintain tension in the fence.

The operator will now simply cut loose the device and the repairs are done.

Janse van Rensburg sells his device for R500 (K500).

Enquiries: Michris Janse van Rensburg – 0027 73 454 4111 or