Office Chair Lift Cylinder Repair Spacer (Customizable)

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The lift cylinder in my office chair stopped lifting when I pulled the handle, so I removed the base and installed a fixed spacer of the desired lift height instead of trying to replace the lift cylinder. Here is a simple 3D-printable spacer that you can customize to a desired fixed lift amount (change the length either in your Slicer program or in OpenSCAD). If you don't want to bother printing, you can also create a spacer using a piece of 1/2" Schedule 40 PVC cut to the desired length. It's a 5-minute installation, but I used a plastic drop cloth to keep the greasy bearing & washers from landing on the carpet. Steps I followed: 1) Put chair on side and extend lift cylinder fully by pulling on base and lift release handle. 2) Remove clip on bottom. 3) Pull off base of chair. Caution: 2 washers and a sandwiched bearing may go flying... 4) Remove the two washers and sandwiched bearing from lift cylinder piston shaft (if they didn't already go flying when the base was pulled off). Clean up any oil/grease that leaked out of the old lift cylinder. 5) Slip the new spacer over the lift cylinder piston shaft. 6) Reinstall the two washers and bearing on the end of the shaft. The bearing with the smaller diameter hole was installed on the shaft first (if they're not the same). 7) Reattach chair base; the shaft should poke through the hole. 8) Reattach the clip. And voila, the chair is now 3.5" higher and doesn't shrink down anymore. Here's a pretty good video showing chair base removal (video also shows complete lift cylinder removal which I didn't do): https://www.youtube.com/watch?v=zBB8DQQrvek NOTE: If you prefer, there are other repair methods involving a clip on the outside of the chair's lift cylinder and doesn't require chair base removal and hence may be easier to alter the fixed height, but in this design the fix is completely hidden (and requires less PLA). Without a working lift cylinder, note that the chair will no longer squish down at all when you plop into it, even after you restore it's height with this spacer. To add a little "give" when you sit down, you might try printing this spacer with a more rubbery filament such as TPU.