I try to build a "grid" with rolled up fences.

But now I have problems with the alignment of the headers of these fences...
Its not possible to place f.e. 10 fences in one column with the same distance.
I enabled the option that there should be 5 pixels distance between the fences
but it seems that this is not workin properly...
In every column there are some distances which are bigger and its hard with pressed Shift 
to align the fences manually...

Are there some tips what causes this problem and how I can avoid this?

THX