Okay, I tested two different nib sizes on grosgrain ribbon: 01 ( .025 mm nib ), 05 ( .45 mm ). The larger nib "ran" slightly, while the smaller did not. I would suspect though that part of the problem experienced was with the lines on the ribbon itself rather than with the pen. Unfortunately, I don't own any satin ribbon, so I can't check them out for you.
__________________ - dlm., lurker extraordinaire
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