This is inside my two Jinhao 10 pens. First image is the red one, second is the coffee one. In both cases you can see the adhesive is really sloppy around the part containing the trap door. The trap door itself seems to be OK. I'm turning a light on/off in front and you can see light coming through, so it would appear that's likely where air is also coming through, making it dry out faster.
Not sure if/how that could be fixed but I have a couple ideas.
First idea is to find a way to apply a coat of something to seal it around that ring, like UV cure adhesive. No idea how I would get it into that spot, though, since it is such a tight fit.
Second idea is to use adhesive remover and disassemble it, clean it up, and reassemble it with better (or at least more consistent) adhesive.
Perhaps a third method will present itself...
The Majohn A1 and A2 didn't have any similar problems. No visible light coming through. They seal decently, though.
They were much dirtier inside. I need to clean those a lot better before I ink them again.
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