The lifting assembly is the components that are used to ‘pop up’ the roof section. Unless it’s a pop-top camper with its cable and winch system, most pop-top lifting assemblies are quite standard. These standard components all assist when raising and lowering the roof section and typically comprise of spring scissors, gas struts and in most cases today – ‘easy lift’ bars.
Gas Struts
Gas struts were first used in Australia in the late 1970s and were installed to the pop-top roof section of campervans such as the Toyota HiAce and the VW Kombi. They assist by pushing the weight of the roof up when the roof is being raised and absorbing the weight when the roof is being lowered.
How do Gas Struts Work?
A gas strut is fully open when it is in its natural state because compressed gas is pushing on a piston inside the strut. When the pop-top roof is fully raised, the gas strut is in this natural state, however, when the pop-top roof is lowered, the gas in the strut is compressed even more. This is how it assists by taking some of the load or weight of the roof section. Gas struts need to be cycled, which means the roof needs to raised and lowered every now and then (one or two times a month). The reason for this is because every time the strut is cycled, the seals are automatically lubricated with a tiny amount of oil. This oil is needed not only to ensure that the seals work properly but also to keep the compressed gas inside the strut. If the seal dries out due to constant non-use, the compressed gas may slowly leak out and therefore reducing the strength of the strut.
Measurement of Gas Struts
Gas struts are commonly measured in newtons (or N) which is the internationally recognised measurement of force. Since a 1kg weight on the Earth’s surface works out to be 9.8N, a gas strut that is rated at 400N will provide a lifting capacity of approximately 40kgs. 500N will approximately equate to 50kgs, 600N to 60kgs and so on.