Why do plotted lineweights sometimes differ from what you see on screen?

[indiancad]

A drawing may look properly organized with different lineweights assigned to layers, but the final PDF or printed output can look completely different. Some lines appear too thick, while others become difficult to distinguish.

One possible cause is a mismatch between layer lineweight settings and CTB/STB plot style configurations. The PLOT settings and selected plot style table can override the appearance you expect.

When your plotted output doesn't match the drawing display, what do you check first: layer properties, CTB/STB settings, or plot configuration? Have you encountered any less obvious causes?

[SAFeSTeR]

I don't seem to have this problem these days but I would think it's just something you need to solve by trial and error until you get the result you desire. I'm sure you're aware of the 'scale lineweights' option in the plot settings which may help but I haven't experimented with this.

I rarely set a layer to anything other than the default lineweight (0.25mm), nor do I use custom plot styles, preferring to use acad/lt.ctb instead. For polylines I always set a global thickness and for the symbols (blocks) I create I usually set all object lineweights within it to 0.00mm as they are fairly detailed and most often used at a small scale, using a higher setting will likely blur that detail.