Recently bought a Pelikan 400NN cheaply on Ebay has a fine nib and wondered how it would write with a medium one. Anyway the nib unit seemed quite stiff when I tried to unscrew it, so soaked it for a while and tried again.
This time the nib started to move, but after a few turns, the nib and feed came out leaving the collar still firmly screwed in the neck of the pen. I managed to push/twist the nib and feed back in, filled up and got too much ink flow, the pen flooded badly. After a few attempts I managed to remove and adjust the nib and feed so that at the moment it seems to be writing OK (but will have to use a bit more to see if this is a 'permanent' fix).
If it carries on working OK, I wil probably leave well alone, but just in case, does anyone know a way of unscrewing the collar from the pen, so that I can either fit it to the feed or replace the nib with another one. I don't think that it will come out with the nib/feed as it seems fairly solidly seized.
Any suggestions gratefully received.