Originally Posted by katwalk
I guess it sort of depends on the inks you use with your pens, I tend to use India Ink and find that I need to clean my nibs at least once (sometimes more) during a drawing session as the ink can dry on the nib
Kathy makes a good point, and even within the Indian Ink family, each brand is different. Some are very dense, and some have more shellac (the waterproofing agent). There are now acrylic inks too, which of course contain acrylic resin as the waterproofing agent, which can also cause buildups on the nib. I keep a small container with some pen cleaning fluid to clean off any excess of dried ink that occurs while I'm drawing. The test is, is it affecting your line? If your line seems to become unwieldy, a quick clean might be in order.
This is the cleaning fluid recipe that Kathy was referring too:
In a large jug, mix:
3-1/4 cups water
1 cup ammonia
1/4 cup rubbing alcohol (I used methylated spirits)
1 tsp. dish washing liquid.
Store in a plastic bottle.