lilypond instrumentName breaks geometry

Question

I have a score which looks great, until I try to set the instrumentName:

Without instrumentName:

With instrumentName:

\score {                                                                        
  \new StaffGroup <<                                                            
    \new Staff \with {                                                          
      instrumentName = "Baß Tube I&II in B"      
    }{                                                                          
      \transpose c bes                                                          
      <<                                                                        
        \new Voice = "TenorIb" { \voiceOne \tenortubaib }                       
        \new Voice = "TenorIIb" { \voiceTwo \tenortubaiib }                     
      >>                                                                        
    }                                                                           
    \new Staff \with {                                                           
      instrumentName = "Baß Tube I&II in F"    
    }{                                                                          
      \transpose c f                                                            
      <<                                                                        
        \new Voice = "basIf" { \voiceTwo \bastubaif }                           
        \new Voice = "basIIf" { \voiceOne \bastubaiif }                         
      >>                                                                        
    }                                                                           
    \new Staff \with {                                                          
      instrumentName = "Kontrabaß Tuba"          
    }{                                                                          
      \clef bass                                                                
      \tuba                                                                     
    }                                                                           
  >>                                                                            
} 

Answer 1

The paper block is used to set values such as the indention values.

To make enough room for those (long) instrument names you'll need to set the indentation value to something greater than the default (15\mm), say:

\paper {
    indent = 35\mm
}

If you are also using short instrument names (e.g. shortInstrumentName = "Btb.") you can set the short indent value (default 0\mm) in the paper block too, with say: short-indent = 10\mm.

---

You can use units other than \mm (millimetres), such \cm, \in, \pt.

Other paper block variables can be found here: https://lilypond.org/doc/v2.24/Documentation/notation/horizontal-spacing-paper-variables