A sinking chair is a nuisance that you shouldn’t spend hours trying to repair with little success, which is why we’re going to share four quick and easy methods to fix your chair.
Before getting into the solution, let’s first look at what causes this problem in the first place.
An adjustable office chair uses a pneumatic cylinder. Inside the cylinder, there is a double-sided position and high pressured gas.
In the cylinder, the gas travels back and forth when someone adjusts the chair’s height. There is also a valve that locks the chair at the user’s desired height.
If your office chair won’t stay up at all, the only way to fix it is by replacing the cylinder. If your office chair is slowly sinking, however, there are a couple of ways to stop this from happening.
An office chair sinks because the gas in the pneumatic cylinder leaks from the valve’s inner seal or the piston seal.
Here are four ways to stop an office chair from sinking:
Adding a new pipe to the chair will often resolve the issue.
- Flathead screwdriver
- A PVC pipe
- Slide calipers (optional)
- Adjust the cylinder of the chair to your desired height by using the seat adjuster.
- Carefully place the chair upside down on the floor or a table.
- You will see a spring clip and a flat washer in the middle on the bottom of your chair. Grab your flat head screwdriver and remove the spring clip. It may take a little work, but the spring clip should slide off with a bit of prying.
- Now, with the spring clip removed, the flat washer is exposed. Remove the flat washer and set it aside next to the spring clip.
- With those parts removed, you can remove the wheels/cylinder housing. When removing the wheels/cylinder housing, make sure that nothing else comes off with it. To avoid missing parts, remove this piece carefully so that if anything falls out with it, you will see it.
- Set the wheels/cylinder housing aside.
- Now you are looking at the cylinder. Around the shaft, there is a rubber washer, steel flat washer, and plastic washer.
- If needed, adjust the washers to their respective places on the shaft. Slide the rubber washer down towards the bottom of the chair. Then place the steel flat head washer and the plastic washer on the other end of the shaft.
- Measure the length between the rubber washer and the steel flat head/plastic washer. Make sure your measurement only includes the distance between the washers.
- Take a visual estimate of the diameter of the shaft so that the PVC pipe can slide around the shaft. Also, note the diameter of the wheels/cylinder housing, so the PVC pipe is small enough to fit back inside.
- Grab your PVC pipe and cut it to the correct length or see if your local hardware store has a pipe with the correct size.
- Take off the steel flat head/plastic washer and glide the PVC pipe on the shaft.
- Put the steel flat head and plastic washer back on by securing it on top or, if it fits, inside your PVC pipe.
- Put the wheels/cylinder housing back on.
- Secure the base by putting the flat washer and spring clip back on.
The PVC pipe method is cheap and relatively simple.
If your PVC pipe is too long and you can’t put the rubber washer, steel flat head washer, and plastic washer back on, you can either cut the pipe more or dispose of the washers.
The washers are so that when the chair’s height moves, they aren’t just hitting metal. So, keeping the washers is optional since the washers aren’t hitting one another anymore.
If you have a slide caliper, use it to measure the shaft’s O.D. (outside diameter) and the I.D. (inside diameter) of the wheels/cylinder housing.
With accurate measurements, you won’t need to worry about buying a PVC pipe that is too narrow or wide.
With the PVC pipe method, your chair will be in a fixed position, meaning you can no longer adjust the height.
Method 2: Adding Some Lurication (WD-40)
Adding some lubrication to the chair may help.
- Flathead screwdriver
- Put the chair upside down or sideways on the floor or on a table.
- You will see a spring clip and a flat washer on the bottom of your chair’s wheels. Grab your flathead screwdriver and remove the spring clip and flat washer.
- Remove the wheels/cylinder housing and set it aside.
- Take off the rubber washer, steel flat washer, and plastic washer from the shaft.
- Spray some WD-40 on the shaft.
- Slide the rubber washer, steel flat washer, and plastic washer back on the shaft.
- Put the wheel/cylinder housing back on.
- Put the flat washer and the spring clip back on.
You have to repeat this method every six months to avoid recurring sinking.
You could substitute WD-40 for a similar thinner oil (anything classified as a lubricant).
Method 3: Using a Duct Tape
Duct tape may not look great, but it certainly gets the job done.
- Duct tape
- Paper towel
- Gloves (optional)
- Place your chair upside down or on its side.
- Take your paper towel and pour some rubbing alcohol on it.
- Clean the cylinder with the soaked paper towel. You will only need to clean the thinner cylinder that is closer to the bottom of the seat.
- Grab your duct tape and wrap the area where the small and large cylinders meet about 4-5 times (put duct tape on the small side, not the large cylinder).
- Wrap the upper area that is closer to the bottom of the chair as well.
This is a cheap and temporary method. It works for some chairs but may not work for all. You may need to use more duct tape if it doesn’t work.
Sometimes, you just have to replace the whole part to fix the issue.
- Pipe wrench
- New office chair cylinder
- Rubber mallet or hammer
- Place the chair upside down on a table or floor.
- Grab your pipe wrench and tighten the pipe wrench around the cylinder. Tighten it as close as possible towards the chairside – not near the wheels.
- Once tightened, turn the pipe wrench until the cylinder comes loose. Loosen until the cylinder housing easily comes off.
- Place the chair aside.
- Grab the wheels/cylinder housing and use a rubber mallet to remove the cylinder from the wheelbase.
- The cylinder should fall out.
- Grab your replacement cylinder and put it into the base of the wheels/cylinder housing.
- Grab your chair and align the cylinder with the hole in the bottom of the chair.
- Place it on.
This is more of an expensive solution. Use a hammer if the rubber mallet doesn’t work.
Having your office chair sink on its own can be irritating, but there are solutions.
Depending on the type of chair you own, there are several easy ways to stop it from falling under you. All you need are a couple of tools and time to take things apart.
Try one of the above methods to fix the issue, and your chair will be good as new!
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