is it possible NOT to plot an adge of a solid? [i]mean: my problem is not related to removing hidden lines, nor to isolines and silhouette.[/i] [i]have an helicoidal staircase;[/i] With 3dface, I can represent the lover helicoidal surface of the stairs by splitting it in many 3dfaces with hidden edges. Unfortunately i used true solids. The lower rectified surface has many edges, which i'd like not to plot. I tried to "color" them with a color, say, 255 and to set this color with a screenng=0 in the plot style table. No use: when autocad removes hidden lines, ignores that color assignment and plot those cursed edges. Is there a way?