Staff spacing for Z beam

[Helge Kruse]

Hello,

I have a spacing question (once again). I want to write cross staff 
beams like you can see in the attached example.

But this code does not gives the expected result:

\version "2.16.0"
\include "deutsch.ly"

upper = { \change Staff = "upper"  }
lower = { \change Staff = "lower" }

finaleUpper = \relative c'' {
  \key h \major
  \time 3/4

  R2.

  % Properties of the VerticalAxisGroup grob
  % staff-staff-spacing
  %  Used to determine the distance between the current staff and the staff
  %  just below it in the same system, even if one or more non-staff lines
  % (such as Lyrics) are placed between the two staves.
  \override VerticalAxisGroup #'staff-staff-spacing #'padding = #10

<h, dis>8\p \lower <cis cis,> \upper
<h dis>[ \lower <cis cis,>] \upper
<h dis> \lower <cis cis,> \upper |
  \repeat unfold 3 { <h dis> \lower <cis cis,> \upper }
  \repeat unfold 3 { <ais fis'> \lower <cis cis,> \upper }
}

finaleLower = \relative c {
  \key h \major
  \time 3/4
  \clef bass

  %<fis dis''>2.
  R2.
  s2. s s
}


\score {
  \new PianoStaff {
<<
      \new Staff = "upper" \finaleUpper
      \new Staff = "lower" \finaleLower
> >
  }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

But when I uncomment the large chord the staff distance increases and I 
get the required Z beams. I think these are easier to read.
- How can I increase the inter-staff space for the required measures?
- How can I overwrite the angle of the beams to make it horizontal.

I read about spacing issues, but didn't find how it works. I also placed 
the staff-staff-spacing in the \layout block although I don't need this 
extra spacing in the whole score. But this gave no space at all.

I hope you can enlighten me.

Thanks
Helge

Zbeam.PNG
Description: PNG image