I need to replace one of the lightbulbs in my bathroom's lightbulb fixture. The bulb itself is a halopin bulb that inserts with a metal hook, but its covered by a glass cage/receptacle that should just screw unto the metal base in the fixture. That glass cage is stuck. Based on other bulbs in the fixture it is supposed to screw off easily but the one that needs to be replaced is jammed. It's hard to put my full force into it because there is a sconce around it limiting my range of motion (I actually broke the sconce on an identical fixture downstairs trying to replace another stuck part). Any ideas on how I can get the glass off the metal more easily?
Try squirting some sort of grease such as WD-40, or even more natural and thicker oils like olive oil into the part where the glass cage touches the inside metal.
Make sure to hold the fixture downward in the way that you pictured and try to minimize getting grease on the part of the glass which you grab.
Apply a damp cloth to the glass cage and fan the area to cool and thus take some of the pressure off of the thread in the metal. Switch between the damp cloth and setting it out in the sun to compress and decompress the glass, all the while attempting to turn it back and forth.
Hope this helps!
I'd try one of the rubber pads used to improve one's grip on pot lids. Be careful; you don't want that dome shattering in your hand.
Remove the glass sconce first.