I'm trying to subtract a line from a rectangle, but when I do, the line just disappears

[martinf90893535]

The title kind of says it all. I made a design for something I'm making. When I try to subtract a line from a rectangle, the line just disappears, and the rectangle is left without any difference. 

Do I have to remake my entire design with rectangles? Because that's gonna take a while. Is there a way I can just mass convert them? Or am I just doing something wrong with Pathfinder?

[Peter Spier]

Some screen shots might help to explain the problem.

Using Pathfinder to subtract implies you want what is subtracted to be removed. If that's not the case, you might want to use the scissor tool instead to cut the line.

[martinf90893535]

I'm trying to subtract the white from the red, but the white is made out of lines.

[Peter Spier]

I was able to produce something similar by drawing a closed shape like your lines using the pen tool.

I made two stacked copies of that in position over the rectangles (I needed two in order to subtract from both rectangles; select the topmost drawn shape and one rectangle, then run subtract; repeat with other drawn shape and second rectangle), but honestly I think it might be just as fast to simply add some points to the edge of the rectangle using the Pen tool and use the Direct Select tool to reposition them where you want them.

[Eugene Tyson]

How many lines? Can you make one line?

Here's my test - and it worked fine - white stroke in front.

[Peter Spier]

But you lost the little triangle...

[martinf90893535 · Accepted solution]

In the end, I just made a hexagon, and used the edge to make the effect. That allowed me to subtract it.

[Eugene Tyson]

That was expected.