Plastic Office Chair Installation

The installation of a plastic office chair should follow a 'bottom-up' logic, with the specific steps outlined below:

I. General Installation Steps (Applicable to Most Plastic Office Chairs)

1. Unpacking Preparation

   • Inventory the components: This includes chair legs, seat cushion, backrest, screw pack, casters (universal wheels), height-adjustable gas lift (if applicable), etc. Check for any damage or missing parts.
   • Prepare the tools: An Allen wrench, Phillips/flathead screwdrivers, etc. Ensure the installation area has a flat floor and ample space.

2. Install the Base and Casters

   • Align the casters with the sockets at the bottom of the five-star base and press down vertically until fully seated. For threaded casters, screw them into the holes, ensuring all wheels are securely installed.

3. Install the Height-Adjustable Gas Lift (if applicable)

   • Remove the plastic protective cap from the top of the gas lift. Place the thinner end (with the button) of the gas lift facing upwards and insert it vertically into the circular hole in the center of the five-star base. Press down gently until it bottoms out.

4. Install the Seat Cushion and Connect the Base Plate

   • Place the seat cushion face down on a soft surface (such as a carpet or cardboard box) and locate the metal or plastic base plate at the bottom of the seat.
   • Align the base plate with the screw holes at the bottom of the seat cushion according to the instructions (usually marked with an arrow indicating the front side). Use the provided screws to secure them loosely (do not fully tighten for easy adjustment later).

5. Assemble the Backrest and Armrests

   • Align the armrest components with the reserved holes on the sides of the seat cushion according to the left and right markings and insert them or connect them loosely with screws.
   • Align the backrest with the connection points on the armrests and the rear of the seat cushion, ensuring all holes are aligned. Insert the connecting screws and tighten them loosely.
   • After all structural connections are made, gradually tighten the screws in a diagonal sequence to ensure even force distribution.

6. Final Assembly and Securement

   • Lift the assembled seat cushion (including the backrest and armrests) and align it with the installed base.
   • For chairs with a gas lift, simply place the hole at the bottom of the seat cushion over the gas lift and let it settle into place under its own weight.

II. Installation Steps for Specific Model (913 Ledun Chair)

1. Install the Armrests

   • Align the holes on the left and right armrests with the screw holes under the seat. Use six M6*35 screws with M6151 washers, insert them into the holes, and tighten them with a combination wrench (repeat for both sides).

2. Install the Keel Bracket

   • Align the screw holes under the seat with the holes on the keel bracket. Use three M6*30 screws with M6151 washers, insert them into the holes, and tighten them.

3. Install the Lumbar Support Assembly

   • Align the M6*16 screws pre-installed on the backrest with the holes on the lumbar support assembly, noting the direction (pointed end up, wide end down). Insert them from the back and tighten (repeat for both sides).
   • Align the lumbar support assembly with the slot on the keel and secure it with the adjustment knob.

4. Install the Footrest Assembly

   • Remove the four pre-installed M4*40 screws from the small wings on the left and right. Align the footrest assembly with the holes on the curved tube and insert the screws from both sides.
   • Then, remove four M6*35 screws and align the small wings with the holes on the front iron tube of the seat. Install and tighten them (repeat for both sides).

Precautions: Avoid applying excessive force during installation to prevent screw stripping or component damage. It is recommended to follow the instructions or video tutorial step by step.