i have a stuck Sheaffer Imperial Touchdown nib unit. The reason why I want to take apart the section is because I have found ink to be leaking through the threads that hold the nib unit to the whole pen. I have tried to remove it with some heat but it wouldn't budge (maybe due to my hairdryer not being able to reach the release temperature of the sealant). I have managed to remove my friend's one but mine wouldn't move at all. I also can't find any rubber sheets nearby which maybe why I can't unscrew it.
Any suggestions? I have posted 2 photos below.