Classic Doodle I
making marks on paper...

The longest I ever recall working continuously on a piece of art is 11 hours.

I was at the small, private college, working in pen and ink, and I know the nib blotted the paper in a couple of places. In trying to work those big black splots into the piece I just kept adding more and more lines and dots, while my roomie obligingly played records that I liked. I took breaks to go to the bathroom, and (presumeably) drink water and, perhaps, eat snacks. The resulting drawing was no masterpiece, but it was an exuberant celebration of lines and dots, most of them very fine.

pen on ink, NYC sketchbook II; approximately 5-3/4 x 8-1/4; probably made on 22mar2020; photographed 19may2020 1/100 sec, f1.7 panasonic lumix DMC-LX100. Adjusted in gimp, mostly to lighten background & square up image, iirc

I haven't the stamina, physical or mental, to do that now.

If I ever stumble across the piece, which may very well have gone on to become the lining for some squirrel nest or ant colony, I'll post it. Back then I would've been using a fine nib, 100, 101 or perhaps 104 and Higgins India Ink. Nowadays I mostly use disposable technical pens, which alas still do not have the marvellous flexibility of line width that was, in my experience unmatched by those delicate steel nibs. However, by switching between different thicknesses of pens, I can get some of the same effects, and they're a lot less messy, and even more important, require no cleanup except putting the cap back on.

I have unfun memories of cleaning 4x0 technical pens, which while certainly more portable than a fragile nib and a bottle of ink, were appalling to keep functional. Disposable technical pens are one of the disposable items I would be most loath to give up, at least until they invent a free flowing, permanent, non-fugitive black ink for the refillable kind. (I don't see that happening any time soon. The very thing you most want—the permanence once dry—is what makes the ink such a bear when it inevitably dries inside the pen's mechanism, and the finer the line, the worse it is to clean.)[1]

I love making doodles. During that same stint in college I had a philosophy prof who not only made quite beautiful ones but forever validated the practise, one of the great, and completely unexpected gifts of my schooling. And particularly during the past several months, I have been making a lot of them. —This one was made at a friend's house as we chatted, just as the increasing COVID19 restrictions made it clear that long, philosophical discussions at a friend's dinner (or in this case, breakfast) table would be going away.

Like that earlier piece, this one is not particularly cohesive,[2] but it represents a fond memory of a happy time.

[1]And let's face it, most ‘pen and ink’ these days is being done on tablets of one sort or another, so there's not much drive to improve the older tech.

[2]note the delicate floral motif, left center, or the the weirdness in the lower left corner—none of which is really tied to the marks along the right edge of the paper