Unparalleled product knowledge

Choose a project below. You need to first remove the base to do anything.

• How to remove and install a Gas chair base. (See below) For Manual types, click here
• Diagram of a bearing kit with schematic for installing or replacing
• How to measure to replace a gas cylinder (Read below)
• How to remove and install a gas cylinder (Read below)
• How to remove and install a gas column (Read below)

Base Removal

First turn the chair up-side-down so that the and in the center of the base bottom underside can be seen.

Spread newspapers on floor to prevent greasy falling parts from causing stains

With a screw driver or needle nose pliers, lift up the holding clip
upper portion only from the piston rod tip

Withdraw the base while pulling and turning. The base will easily remove from the gas cylinder most likely pulling with it (hidden inside) the 2 washers and ball bearing. Set these parts aside to be reinstalled with the replacement base. There should be 4 small parts. If not, look inside the withdrawn column for the remaining part(s) where usually you will find a washer at the bottom.

Installation and bearing kit information

A replacement Gas Cylinder cannot be measured properly unless the base has first been removed. Optional method

To install or replace a base, first replace the rubber cushion onto the piston rod, pushing it as far up as it will go. Then the large washer, then a lightly greased bearing and lastly, the other large washer. Wipe off greasy hands on the gas cylinder body. Now, slip the base with hub column up onto the gas cylinder. The remaining small washer and clip are then lastly installed onto the protruding piston rod end at the outside bottom of the hub column. These six small parts can all be easily replaced using our very low cost bearing kit #108 with printed schematic.

Abacus uniquely includes a new column (AKA standpipe) with a replacement base. We recommend you use the new column, This is especially important if your chair has a lot of milage on it, as the plastic part inside the the column supporting the gas cylinder is probably worn or perhaps cracked, loose or broken. All of which will cause your chair to annoyingly rock and wobble while in use. To remove the column which often appears that it does not remove, read this.

Installing a Gas Cylinder is accomplished by simply hand inserting the Taper (releaser button) end of the Cylinder into the mechanism. Install small parts of Bearing (kit #108) per schematic, lightly greasing the bearing. Wipe off greasy hands on the cylinder and install base. Turn the chair over into it's normal use position. Sitting on chair once or twice is enough to make the tapered joints fit unimaginably tight.

Click photo to see cylinder selection

There are two types of bases

1. Gas height adjustment chairs (are those chairs having a lever under the seat)
2. Manual height adjustment chairs (you turn a part that looks like this to lower and raise the chair)

View all Gas bases---View all Manual bases

After removing the base from either a Gas or Manual height adjustment office swivel chair, squirt a shot or two of WD 40 at the underside of the base where the Column protrudes out the bottom. Aim where the Column and Base meet. Turn Base over and repeat at the topside of the Base and Column. The WD 40 must run down entering the tight fitting tapered joint to facilitate removal. Do this by sharply striking the side of the Column from 4 directions using a short length of 2" x 4" (14" to 18" will do very nicely) or a steel hammer. The idea is to "Shock" the Column setting up a vibration which will permit the WD 40 to run into the joint. Set the Base and Column aside for 5-10 minutes to permit the fluid to penetrate into the joint.

Then, with the Base with Column underside facing you, lay the 2 x 4 flat on top of the protruding piece of the Column, strike repeatedly with medium/hard blows. Do not use a mallet! Nine out of ten columns can be removed in this manner...sooner or later. If you have a Ten, purchase a new Base with included Column.

It is highly recommended to replace the Style #108 Bearing Kit (each kit includes a schematic) whenever removing the base, column or gas cylinder. A #108 kit if ordered separately does not meet our required $20.00 minimum merchandise purchase.

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Column Installation

The Column does not require any special installation into the Base. Simply inserting the Column into the tapered center base hole is adequate as the weight of the chair and normal sitting will seat the Column taper very tightly after only a single use or two. Insert the column into the center hole of the 5 leg chair base. Do not use any tools to seat it.