How can I take the arms off my desk chair?
They're probably installed with some sort of thread lock.

Try a few good whacks with a hammer to the screw heads. Then use a high torque screw driver (One that you can turn with a wrench), or a vice grip on the outside of the head, or an impact driver.


Make sure to use the correct bit for those screws.  It should be the largest one that fits and doesn't wobble.

Sit the chair upside down, and place YOUR ENTIRE BODY WEIGHT onto the back of the impact driver to avoid stripping another screw head.  Hopefully the one that stripped one will loosen enough with the other three off.  It not, use one of these stripped screw remover bits.



If you have to use those bits, again, place extraordinary backpressure on the back of the impact driver when you do.

If all else fails (say they literally welded the threads in place) you can use an angle to grind away all four screws from both sides.  But be careful not to let enough heat build up to melt or burn the fabric.