Crosspieces for armchairs: what is it, how are they chosen and changed?

Wheeled chairs are a modern invention that helps you work in comfort, move around the room and reduce stress on your back. But with improper use, and especially when trying to swing in such a chair, a breakdown may occur. Most often, the chair cross is subject to deformation. In this article, we will consider why this part is needed and how to properly replace it yourself.

The crosspiece is a durable part of the chair, to which the wheels of the computer chair are attached and which is the support of the chair itself. It is a structure with rays extending from the center to the periphery, to which rollers are attached, and a gas lift from the chair itself is fixed in the central part. It takes on the largest part of the load, evenly distributing it on the wheels located in a circle.

For a complete understanding of what is a cross-piece for a chair, it is worth deciding on all its inherent features and functions.

• Stability. The first and most important function of the crosspiece is to ensure the stability of the chair. If the instructions for use are followed, it prevents the user from overturning and falling, ensuring safe operation.
• Mobility. The presence of roller wheels on the chair makes it easy to move around the room without even getting up from it. You can simply move the chair to another room, without having to lift it and drag it in your hands.
• Strength. Manufacturers today use only high-quality, durable materials for the manufacture of models. They are resistant to configuration changes, load changes and ensure the integrity of the structure for a long time.
• Modern design. A removable crosspiece allows you to choose exactly such a detail that fits perfectly into the interior of the room and directly under this seat model.
• Standard. One of the features of all crosses is that such units are made using a single technology, which makes it easy to replace a failed structural element. Plus, this makes the method of self-removal of the base the same for any other similar cross.
• Fixed crosspiece. If the user is hampered by the greater mobility of the chair, then there is always the possibility of replacing the wheels with so-called gliders (special replaceable legs).

The existing models differ in various parameters. Let's take a closer look at them below.

An extensive selection of materials allows us to develop models for any type of interior.

• Wood - a very popular and stylish option, most often used for the manufacture of custom-made armchairs for important persons. Only strong woods are used, and metal raw materials are used for the middle. The wheels are mounted on a hub with a cap.

• Wood + steel - an option that includes the beauty of wooden models, but at the same time completely eliminates the problems of wood. The peculiarity is that the metal frame gives strength, resistance to deformation and swelling from moisture.

• Chrome steel - this option is budgetary, sturdy, corrosion-resistant and quite easily replaceable.

• Polished aluminum Is a relatively expensive option, but the durability of these products justifies the price. The aluminum crosspieces can carry loads of up to 160 kg.

• Plastic - the most common material, most of the seats sold have just such a base. A plastic crosspiece is a budget solution, there are a lot of models with various designs that can withstand heavy loads.

• Nylon - a fairly solid option for relatively little money. The downside is that such a cross is susceptible to breakage when the center of gravity moves to one side, then self-repair of the broken beam is almost impossible.

Three parameters are used to classify crosses by size. Cross diameter. The beams outgoing from the middle can have a diameter of 480 to 700 mm, so it was decided to divide these dimensions according to the target audience of buyers.

• For children and adolescents. For this category of users, models have been developed that are designed for relatively lower loads and have a smaller size. The diameter of the crosspieces for such chairs is 480–580 mm.

• For office and computer work (adults). This is the most common model of crosspieces, the diameter of which ranges from 600-680 mm. Withstands a greater load compared to the previous ones, it is designed for larger seats.

• For managers (adults). The largest and most reinforced crosspiece, has a diameter of more than 700 mm, providing an even distribution of the load from massive seats, it allows you to install reclining chairs on it, as it better withstands the movement of the center of gravity to one side.

Gas lift hole diameter. There are 2 options.

• Hole 50 mm - the most popular type, most of the gas lifts have a given pipe diameter. It is used in budget models, and therefore allows repair work to be carried out much cheaper.
• Hole 38 mm - for models with massive armchairs (for executives) from the premium segment.

... Wheel hole diameter. There are also 2 size options to consider when it comes time to repair the crosspieces.

• 11 mm is the most common solution, found in most crosspieces, and therefore there is no problem finding wheels for any kind of floor material.
• 10 mm - a rare hole, functionally does not differ in any way from the previous version, it is used in wooden and design crosses.

Reinforcement of the structure is achieved by using durable materials and reinforcing parts. Additional gluing, double welding of seams, attachment of steel corners and threaded elements allow the chair to withstand higher loads compared to unreinforced models. On the underside of material combination bases, there are often plugs that make the cross piece stronger.

The choice of options on the market is quite wide, but there are parameters that will correctly tell you how not to miscalculate with a new chair support. The main criterion that determines both the appearance of the cross and its strength is the material. It is best to purchase a chrome-plated metal one-piece construction. If it does not suit the style, then you can consider special overlays of the desired color. Next, you should decide on the size of the structure, do not forget about the correspondence of the sizes of the holes of the cross and other elements of the chair. You should also not use bases that are too small for small seats, otherwise the chair will be too bulky and unbalanced. Pay attention to the holes for the wheels, in most seats there is a plug, which can be easily replaced in the event of a breakdown.

To independently replace the crosspiece on your chair, you need to prepare the place of work. The entire surface should be covered with newspapers or oilcloth. To remove the cross from the wheelchair, you need a Phillips and flathead screwdrivers, a hammer, and hands.

• For better access, turn the chair upside down and place it in a stable position.
• Detach the seat of the chair by unscrewing the bolts that attach it to the piastre (the part that connects the bottom of the chair to the gas lift).
• Use a flat screwdriver to pick up the plug that holds the gas lift and prevents it from sliding out of the cross hole (located right in the center). If there is a cover, it is necessary to bend the plastic clips and move it gently upwards.
• Remove the pipe from the cross-piece hole by tapping lightly on it until it comes out.
• Inside the gas cartridge are small parts and grease that may fall out during disassembly. Lubrication can smear the whole room, and small details get lost - you should not allow this.
• Pull the wheels out of the old spider with a little force.
• Replace the old crosspiece with a new one and reassemble the structure in the reverse order.

For information on how to choose a crosspiece for the chairs, see the next video.