Hello,
I have one side of my pcb outline done and I want to mirror it and have it line up on the other side, I tried copy and pasting then flipping, but flipping always flips about the center of the selected edge cuts so I lose my relative position. Is there a way to mirror the edge cuts about a certain axis, or flip not about the center of the selected cuts so I can line it up properly afterward?
Thank you!
Highlight your edge cuts, Duplicate, then Mirror, the duplicate.
Duplicate & Mirror functions are in the RH Select menu. Mirror functions are also up top and can have hotkey assignment.
I wonder why you want to do it?
Maybe to create a symmetrical outline?
Especially if the outline is complex . . . 
Mirrored outline will be symmetric to original. It is obvious.
But what I wonder is - why someone can need it?
Thinking a while - left hand half-keyboard being symmetric to right hand half-keyboard?
Pay attention to the beginning of the first post. One outline, symmetrical around y-axis. Thatās how I understand it. You can draw left side of the outline first, then duplicate and mirror, then position it so that it continues the lines from the left side. In any CAD program, I believe you donāt want to draw left and right wings of a butterfly separately, but want to mirror one wing.
As said before: Complex PCB outlines. Something like:
Note that flipping is not the same as mirroring. With flipping you move objects from the front to the back of the PCB (or visa versa). For layers that do not have a front/back pair, it does resemble mirroring.
KiCadās drawing capabilities are very simple / sparse. KiCadās developer team is still quite small and the recommended path for complex PCB outlines is to draw them in an external program and then import them in KiCad.
Itās for a controller!
I am in V8.
In test design I have rectangle edge cuts. I select it and from context menu select āMirror Horizontallyā and it is mirrored not about its center, but about its left edge.
Even if mirroring about certain axis is not possible you can afterwards use from context menu the function: Positioning Tools - Move Exactly or Move with Reference or Copy with Reference.
Explains me nothing.
Controller is the man who have to see exact picture of opposite PCB outline?
Controller is the other PCB that you want to see how this PCB fits there?
I am currently designing a device containing 4 PCBs one on the another and each having different shape. I am all them designing from the front side of device view even for 2 of them that means all footprints are at bottom.
What would be some good external programs to draw the pcb in? (preferably free!)
The PCB is best designed in KiCad.
But you probably mean the PCB outline. There is a bit of a distinction between āfreeā and FOSS
I use FreeCAD myself, but it has a bit of a convoluted learning curve. Some people like Inkscape but for some reason I canāt wrap my mind around their workflow. LibreCAD is an option, but there is very little development going on there. Apparently Krita can work with SVG files, but I never used it. In general, any program that can export either SVG or DXF should work.
Letās say that some of itās edges are not rough. But itās worth learning if you ever will want to create a 3D model with something which is FOSS; and it has the StepUp workbench which can communicate with KiCad files. Good for several purposes, including PCB outlines.
Advantage or disadvantage? 