Old-Style Office Chair Installation

The installation steps for an old-style office chair can be divided into five parts: base components, seat cushion and chassis, backrest, armrests and headrest, and other components. The specific operations and precautions are as follows:

I. Base Component Installation

1. Connecting Chair Wheels to the Base: Insert each chair wheel (caster) into the assembly holes of the five-star base one by one, ensuring that each wheel is fully embedded and secure. If the base is made of metal, check the holes for burrs to avoid scratching your fingers.
2. Installing the Gas Lift: Flip the five-star base over and vertically insert the thicker end of the gas lift into the center hole of the base, ensuring a tight fit between the gas lift and the base. The gas lift is the core component for adjusting the seat height, so avoid tilting it or applying excessive force during installation to prevent damage.

II. Connecting the Seat Cushion to the Chassis

1. Securing the Chassis: Place the chassis on the bottom of the seat cushion, paying attention to the orientation (usually, the chassis has markings or grooves that correspond to the direction of the seat cushion). Align the screw holes and use screws (such as B screws) to initially secure it, tightening each screw 3-4 turns before fully tightening them one by one to prevent the chassis from shifting.
2. Connecting the Seat Cushion to the Gas Lift: Align the chassis hole at the bottom of the seat cushion with the top of the gas lift and gently press down to fully insert the gas lift into the chassis hole, ensuring a secure connection. If the gas lift does not match the chassis hole, check for incorrect installation or damaged components.

III. Backrest Installation

1. Connecting the Backrest to the Armrests: Align the bottom sides of the backrest with the armrest installation positions on both sides of the seat cushion, insert them vertically, and use screws (such as C screws) to secure the bottom of the backrest from the bottom of the armrest brackets, ensuring a tight connection between the backrest and the armrests.
2. Securing the Backrest to the Seat Cushion Bracket: Align the installation holes at the back of the backrest with those on the seat cushion bracket, use a wrench and screws (such as D screws) to lock them in place, and check if the backrest can recline or lock normally to avoid loose screws causing the backrest to wobble.

IV. Armrest and Headrest Installation

1. Installing the Armrests: Press the button below the armrest surface and insert the left and right armrests into the holes of the armrest brackets respectively. A 'click' sound indicates that they are properly installed. If the armrests cannot be inserted, check if the button is stuck or if there are any foreign objects in the holes.
2. Installing the Headrest: Place the headrest in the middle position at the top of the backrest, press it to ensure a snug fit, and use screws (such as E screws) to pass through the fixing clips and tighten them, ensuring that the headrest can be adjusted up and down or fixed in place.

V. Other Components (Optional)

Some models (such as 908/909) require additional installation of backrest brackets, connecting trays, or footrests. Use dedicated screws (such as M625mm, M820mm) according to the instructions for fixation. Before installation, verify the screw specifications and quantities to avoid mixing them up, which could lead to structural instability.

Precautions:

• Screw specifications and quantities may vary by model. Before installation, confirm the parts list to avoid omissions or incorrect usage.
• Pay attention to the orientation of components during installation, especially critical parts like the chassis and backrest. Incorrect orientation may render them unusable.
• All screws should be tightened to an appropriate torque. Loose screws may cause structural wobbling, while over-tightening may damage the threads or components.