A fountain pen can write cleanly in one notebook and leave a fuzzy mess in the next. Try another sheet before you blame the pen or swap the ink.
Fountain pen ink is liquid. Some paper soaks it up too fast. The ink spreads along the fibres and doesn’t stay where you put it.
How paper started
Paper was first made in China. Cai Lun gets the usual credit, AD 105, although scraps survive from several centuries earlier. He improved the way it was made.
Early papermakers used plant fibres. Rags and fishing nets went in. They broke the fibres down in water and lifted them out as a thin layer. Drying did the rest.
What happens when ink touches paper?
Little hairs along the edge of the writing: that’s feathering. Ink on the other side of the page is bleed-through.
Papermakers slow this with sizing. It can be mixed in during production, or put on the surface afterwards. Either way, it keeps the ink from spreading through the fibres.
The surface is a separate matter. A smooth sheet lets the nib move easily. Some people want a little texture. Paper that absorbs slowly leaves you waiting. Turn the page too soon and you smudge the line.
Don’t go by thickness. GSM is grams per square metre: weight, nothing more. Thin paper can take fountain pen ink. You may still see the writing as a shadow on the back. That shadow is ghosting. It doesn’t mean the ink has soaked through.
Paper brands to try
Leuchtturm1917 notebooks use smooth 120 gsm paper.
Lochby journal refills use 68 gsm Tomoe River very thin paper made for fountain pen ink.
Filofax‘s notebook range includes 100 gsm paper, though weights vary by refill, so check before buying.
Rhodia‘s orange and black pads use smooth 80 gsm paper, ideal for loose notes.
For letters, Original Crown Mill makes matching paper and envelopes. Their Pure Cotton is soft, while the laid paper gives the nib more texture.