After last week I took the initial gears and made them from solid gold, not is time to talk about the completely different approach, old writing on old paper, where we will work on the strokes.
So, back to the black and white gears:
If we set the stroke color and unset the fill color will get something like this, with overlapping contours, he will have to get rid of:
So select the gear (gears if we have more) suffering due to this unwanted overlap and convert the stroke to path:
The go to another gear which covers it, duplicate, select the duplicate and the former stroke and do a difference operation:
Repeat with all the gearc covering it until we get to something like this:
Then convert all the remaining strokes to paths.
Now we want the drawing to look rough. But it has a large number of nodes, it will take quite a while to edit them manually for the desired rough look, so, as usual, I will cheat and use an automatic simplify operation (shown at an increased zoom level):
Repeat for all your gears and get something like:
Now define a multistop gradient for the paper - light grown/yellow for old paper or dark blues if we want to go with blueprint (I have not decided yet about the way to go).
A multistop gradient is needed for ink too (not shown), and it has to have fitting colors but good contrast with the paper (like browns for old paper and light blue for blueprints). Apply the gradients:
Then add some texture to the paper: draw a random blob with the freehand tool, will it in a color similar with the background (but slightly darker or lighter), unset the stroke, simplify if needed and blur a lot:
Add some more until you are happy with the texture:
The images is still too sharp for an old drawing on old paper, so we will have to soften the focus. Select all the gears, duplicate, make the duplicate darker (black), apply some blur and decrease the opacity:
And this is all for now:
I still want to tweak this design further, I am researching for an additional effect which I am not sure how to achieve (yet): I want to make the paper look like it was folded (probably a combination of random shapes and blur).