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In response to the ever-increasing number of unsafe aftermarket components hitting the market, the Low Volume Vehicle Technical Association (LVVTA) has developed a purposebuilt cyclic test rig. The rig, for which the major fabrication work was donated by Wellington metal fabrication business Metcon, was unveiled to the public at CRC Speedshow, where it was configured to replicate light driving forces on an aftermarket tiltadjustable steering column — although this is just one of many uses that the LVVTA has in mind for it. The desire to build the cyclic test rig came about as a result of the catastrophic failure of an aftermarket tilt-adjustable steering column in 2013. This failure was traced back to a small plastic component within the tilt mechanism of the column. From this failure, the LVVTA began the process of formulating a method by which quality aftermarket tilt columns could be distinguished from poor-quality items. While some components may easily pass a one-off load test, most automotive components undergo a high number of cyclic — repeated — loads. With this in mind, a specialist design engineer was commissioned to design a cyclic test rig that could replicate those loads. The rig incorporates an electronic actuator that can apply loads of between 2.5kg and 60kg, measured by an electronic load cell fitted to the rear end of the actuator. This sends a signal to the electronic controller, and all data relating to every movement the actuator makes and the loads applied are recorded. The rig’s design allows for columns to be tested at a range of angles, including their maximum tilt setting — a position in which they’re often driven in hot rods and pickups, and a situation that creates the highest loads such a column will receive. Unlike the LVVTA procedure for cast I-beam axles, this is a destructive test, where even a column that passes will be worn and unsuitable for use in a vehicle. If a manufacturer has shown that its production is consistent and to a high quality, the result from the cyclic testing of one column can be used to justify the integrity of others of the same make and model. As unproven and poorly constructed products are becoming increasingly common in the aftermarket, the cyclic test rig has been designed in such a way that it can be used for numerous different components and is not limited strictly to steering products. This will enable the LVVTA to prove — or disprove — the quality of components intended to be fitted to low volume vehicles. Further information on unsafe steering columns, and a detailed explanation of the original column failure, can be found in the Unsafe Aftermarket Steering Columns info sheet No. 01-2013 at lvvta.org.nz.