When drawing robots to be colored by hand I generally ink with one line thickness. The term inkers sometimes use is “dead line weights.” I add thicker lines when I’m finished with the marker colors because the marker will dull some of the ink and I would have to go over the thicker areas again anyway. You can see how the lines are beefed up a bit when the colors are finished in the Transformers art below. (Scroll the line left and right compare.)
You can view more of my Transformers art in my gallery.
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