Hi everybody. I am looking for advice regarding a couple of Waterman fountain pens with
extra-fine nibs. I have two fine-point fountain pens (a Cross and a Sheaffer) that write
beautifully with any ink. I also have a couple of extra-fine Watermans (a Carene and a Preface II)
that only write well with certain water-based, shellac-free inks. Other inks e.g. Pelikan Black, just don't
flow easily from those extra-fine nibs. I'd like to know if this a bug or a feature of extra-fine Watermans?

The Waterman repair people have understandably asked me to send them the pens for examination, but
I'd rather not bother them if this is just a case of Waterman extra-fines performing as they're supposed to.

I should add that I clean the pens regularly, and that they have never been damaged,