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How do I remove my shower knob?
I am trying to replace my shower knobs. The basic removal is Hot/Cold button, screw, then pull knob and it releases from the shower stem. The stem from the cold side looks like a cube so I am assuming the hot side does also. After removing the knob from my cold side I am having problems removing the hot knob. The knob seems fussed to the stem. Any ideas on how to remove the knob?
Probably, the hole started to round out -sort of a square-peg in a round-hole situation -- common when the valve starts leaking and people turn the knob harder and harder to try to get the water to stop dripping. This typically happens on the hot water valve (the hot water breaks down the valve washer faster). I don't suppose you've got a slow leak from the shower head? 
Turn it all the way on, then force it a little further, and you'll probably feel it give a bit as it twists back to it's normal position -- of course, you probably won't be able to turn it back off without it jambing again. You might want to turn off the hot water at the water heater first.
If twisting it the other way doesn't free it up, you'll have to pry or cut it off. To pry, use a claw hammer and put a block of wood under it to protect the shower wall. Be careful to direct the force directly away from the wall - you don't want to torque the valve stem -- also be careful if it's a flimsy fiberglass enclosure. If prying doesn't do it, you can cut and break it off. Using a handsaw, cut a slot parrallel to the valve (staight out from the wall). Cut a 1/4-1/2" slot, and then use a large screwdriver or pry bar to wedge the cut open, and the handle should break in two.
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