A little theoretical mechanics
As mentioned above, cantilever sliding gates are the most complex and expensive design. The moving leaf rests on 2 points located on the side, near the gate post.
To understand why gates with a cantilever structure are more complex and expensive, let’s turn to the basics of theoretical mechanics: we will conduct a visual practical experience. Take a household scale (floor or kitchen) and a wooden bar about 700 mm long. Let’s imagine that this bar is our gate design. We will weigh the bar and remember the readings. Now let’s set the bar-beam horizontally so that one end of it rests on the scale, and the second — on the support (for example, on an inverted glass). We will get a layout of a beam with two supports.
If you look at the scale readings, you will see that the value has decreased by about half. This is why suspended sliding gates are more reliable and simple: the load is evenly distributed on 2 support pillars.
Now let’s make a model of a cantilever beam, that is, a horizontal beam that is fixed only at one end. Fix the end, which is supported on the scale. This can be done by putting the end of the bar under the door of the kitchen Cabinet or simply holding it with your finger. Just do not create additional pressure — just hold the bar, not allowing it to tip over. And the second support (glass) will be removed.
If you look at the scales, you will find that their readings have increased almost 4 times compared to the original ones, when we just weighed the bar. Naturally, if you put something on the free end of our cantilever beam-bar (for example, an Apple that will simulate the weight of the gate leaf itself), the load on the support will increase even more. Now, knowing the weight of the gate, you can roughly estimate the required cross-section of the support cantilever beam and the power of the Foundation for roller supports.
Location of the cantilever beam
As mentioned above, the cantilever beam can be at the bottom of the gate leaf, in the middle or on top. The most common (but not the best) option is with a lower location, as in the diagram above, although there are many positive aspects.
Indeed, at the lower position, the load from the weight of the sash on the beam is less. The load on the Foundation is also lower, because the higher the center of gravity is raised, the more powerful the support should be. And externally, the gate structure itself looks more aesthetically pleasing: the moving mechanisms of the carriages are hidden inside the guide beam, and it does not stand out too much from the frame of the gate.
However, with this arrangement of the guide beam, the mechanism that drives the sash is also installed almost on the ground. This means that it is more susceptible to adverse conditions: in summer it is flooded with rain and splashed with mud, in winter it is covered with snow.
In the cold season, there is another problem-the lubrication of the rollers freezes. The standard set for the lower beam includes 2 carriages with 8 rollers each. Difficult movement of the mechanism increases the load on the electric motor of the drive. The number of rollers, which means that places that require lubrication, can be reduced by increasing their diameter. This facilitates the movement of the gate leaf at any time of the year, and increases the service life of the drive.
Both of these problems are offset by the installation of a beam in the middle of the gate, but this design is less aesthetic: all the mechanisms are visible. In addition, not all companies engaged in the installation of sliding gates are able to produce this version of the design, because most of the components are offered for the lower location of the console. Even less common is a structure with a beam located at the top of the sash.
The device of the gate with your own hands
Sliding gates consist of elements that are manufactured on site (for example, the Foundation), and standard ones that are available for sale. Therefore, a householder who knows how to use the tool, it is quite possible to assemble and install them yourself. First, you need to choose the right place for the gate and its size. These factors depend not only on the location of the house and flower beds, but also on the access road to the site: if the passage is narrow, the gate will have to be made wider.
When choosing accessories for sliding gates, you need to take into account the size of the sash and its weight. The metal frame is assembled from profiled pipes, the gate leaf is filled with sections of fencing, taking into account the tastes and capabilities of the owner. The frame can be welded or assembled mechanically: using bolts. An important point is the application of a protective coating. The better you paint and paint the frame, the longer you will not have to remember to repair the gate.
Some companies offer kits for self-Assembly – manufactured and factory-painted gate elements.
For installation of roller supports, a reliable reinforced Foundation with an installation platform is made. Its size and depth of laying depend on the weight of the gate and the depth of soil freezing.
For more comfortable use, the sliding gate is equipped with an electric drive. The force from the rotation of the motor shaft is transmitted to the toothed rail attached to the gate leaf.
The engine power is also selected depending on the weight of the movable structure. To install the electric motor that opens the gate, do not forget to pre-lay the cable (the required core cross-section is indicated in the passport of the electric drive). In addition, you will need additional power cores or low-current wires if you plan to remotely control the opening of the gate, lighting, magnetic lock, installation of an intercom or video surveillance.
You can insert a gate into the gate, but it is more convenient to make the entrance for pedestrians separately. Using it will be more comfortable for children and elderly family members, and you will not have to cross the threshold with a stroller or Bicycle.
Here, in General, is all the information necessary for an initial acquaintance with the device of sliding gates. Do you plan to install such gates on your site?