I've just got a Kaweco piston filler, with a "Warranted ... " nib. Piston works smoothly (but not freely!) but does not fill at all. Not a single bubble expelled when working with it. Cork most probably needs replacement.
Piston driving assembly seems to be just screwed from the top, but if anyone has already destroyed one of these I would like to receive his/her advice...
TIA
Martin
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