lilypond: Odd horizontal spacing with two voices

Question

In the example below I get an unwanted large horizontal gap between the d and the c. I think it has to do with a conflict between \voiceOne an \voiceTwo, because alone they are typeset properly.

Maybe it is a simple thing, that I've overlooked?

\version "2.19.82"

voiceGrundbass = \relative c {
  \override Stem.direction = #'DOWN
  \omit Stem
  \set fontSize = -3
  s1 g4
}

bassLine =  \relative c' {
  \set fingeringOrientations = #'(right)
  \clef "bass"
 <f,-1>1
 \set fingeringOrientations = #'(left)
 <d-5>
 \set fingeringOrientations = #'(right)
 <c-1>
 <c-1>
}

fb = \figuremode {s1 <6 4 3>1 }

% The score definition
\score {
    \new PianoStaff \with {
      \override BassFigure.font-size = -2
      \override BassFigureAlignmentPositioning.staff-padding = 4
    }
    <<
      \context Staff = "1" \with {
      }
      <<
        \time 8/1
          \new Voice= "1" { \voiceTwo \bassLine }
          \new Voice= "2" { \voiceOne \voiceGrundbass }
        \fb
      >>
    >>
  \layout {
    \context {
      \Staff
      skipBars = ##t
      \remove "Bar_number_engraver"
      \remove "Stem_engraver"
    }
  }
}

Answer 1

Change your code for the Grundbass, by adding *4, to the note g4. This scales the duration value (and hence spacing) of the note (but not the note symbol).

That piece of the code will now look something like this:

voiceGrundbass = \relative c {
  \omit Stem
  \set fontSize = -3
  s1 g4*4
}

This gets rid of the large space between the D and C:

It still looks a little unbalanced, but this is just because of the figures on either side of the notes; the notes are now equally spaced horizontally.