How Guides and Stops work for Sliding Gates
Sliding Gates require a system of guides and stops to hold the gate up even when moving.
At the closed end is a keeper that the gate closes into holding it in place. It also prevents the gate closing too far so acts as a hard stop too.
The keeper is flared to allow for a situation for when the wind or other force on the gate may cause it to by out of alignment and it guides it back into alignment.
A sliding gate must also have a guide system to hold it up while it moves. The simplest way to do this is using a pair of rollers.
Guide rollers are suitable if the top of the gate is straight, doesn't rise or fall very much and there is no timber or metal cladding fitted to the front face of the gate (face mounted).
Nylon Block and Rail
This system has an Aluminium guide rail fitted to the back of a sliding gates top or middle rail that slides through a nylon block that can move up and down in an extruded aluminium channel. Aluminium is used because it is smooth and provides the least amount of friction. The channel may be fitted to either a guide post or "U" shaped mounting bracket that goes over the top of the gate from the front gate post. The advantage of the "U' channel is it is more economic but does require the very top of the gate (including face mounted cladding) to be lower than the post other wise the bracket may be visible.
A block and rail guide system leaves the front of the gate free for cladding and allows the gate to rise up hill as it moves, although if the guide rail is on the same angle as this slope then the whole guide system must be on the same angle.
If the top rail is curved the guide rail should be fitted to a middle rail of the gate and a short guide post installed behind the gate.
The guide rail length is the same as the width of the gate plus and extra 50mm to make sure it passes through the block properly when the gate is fully closed.
Open Hard Stop
The gate must also be prevented from opening too far because if it does it may come off the guide system and fall over, which can be dangerous.
Preventing the gate from being lifted to gain access into a property
If a gate is light weight there is a possibility that a very keen burglar could lift the gate off its track to gain access into your property.
Two pieces of angled steel or aluminium can be used to prevent the gate from being lifted off the track, one fitted to the post and the other to the gate so they line up when the gate is closed. The gap between them should be 5 to 10mm to allow for any ground movement but not too much other wise the wheel can be pulled off the track.