Loose Backrest of Shengao Office Chair

The loose backrest of a Shengao office chair can be resolved by identifying the loose location, implementing targeted repairs, adding physical support, using fastening devices, replacing damaged parts, or applying emergency reinforcement methods. Here are the specific steps:

1. Identify the loose location
First, test the degree of wobble when leaning the chair back. If there is a clicking sound, it is likely that the adjustment rod screws are not tightened properly. If the chair back lacks rebound force, the spring or gas lift may be aging. Use a phone flashlight to observe if there are any obvious gaps at the connection point below the chair back to initially determine the root cause of the problem.

2. Targeted repair solutions

• Loose adjustment rod screws: Use a Phillips screwdriver to rotate the plastic cover at the base connection counterclockwise. After exposing the metal fixing frame, use a wrench to tighten the 6-8 fixing screws one by one (you can operate symmetrically at 90° intervals to prevent uneven force).
• Spring detachment: Locate the spring bolt at the bottom of the chair back. Use needle-nose pliers to re-insert the slipped spring hook into the slot. If the spring is deformed, measure its original length and purchase a replacement spring with a diameter of 3-5mm online (the price is about 5-15 yuan).
• Excessive gap in the gas lift: Remove the dust cover at the bottom of the seat. Find the gas lift adjustment knob (a black plastic part) and rotate it counterclockwise to increase the support force. Test the rebound resistance in stages of 30° during adjustment.
• Adjust the mechanical structure: Locate the chair back adjustment knob (located under the seat cushion or on the side brackets). Use an Allen wrench to turn it 3-5 circles clockwise to test the tightness.

3. Add physical support
If the screws are tightened to the limit but still loose, you can insert books or hard plastic sheets at the angle between the chair back and the seat cushion. It is recommended to cut an old mouse pad into 30cm strips, stack them in multiple layers, and fix them with double-sided tape. This ensures support while avoiding discomfort.

4. Use fastening devices
Wrap an elastic band around the backrest frame in a criss-cross pattern or use 3M Velcro straps to fix the backrest angle. These materials can be purchased at stationery stores or hardware markets. Note that leave a 2cm margin of movement at the end of the band to prevent excessive restraint on the moving axis of the frame.

5. Replace damaged parts
If there is an abnormal noise when the gas lift is raised or lowered, replace it with a gas spring that meets TUV or SGS certification. If the plastic buckle on the chair back is broken, you can use AB glue for temporary fixation, but it is better to purchase original factory parts for replacement. Search for "office chair repair kit" on Taobao to obtain universal screws, buckles, and other parts. If the chair has been used for more than 5 years, the fatigue value of the metal parts is close to the limit, and the repair cost may exceed 40% of the price of a new chair. It is recommended to replace it directly.

6. Emergency reinforcement techniques
If you have no professional tools, you can make temporary repairs: Cut a bicycle inner tube into 3cm wide strips and wrap them around the joint between the chair back and the base to increase friction. Or use rubber bands to tie the moving joints of the gas lift to limit the degree of swing. Such operations can maintain stability for 3-7 days.

Daily maintenance advice: Check the tightness of the screws every quarter. People weighing more than 80 kg should pay special attention to the wear and tear of the gas lift.