instrument name padding

[Jonatan Liljedahl]

I'm trying to add some padding after the instrument names (they touch
the bracket), I've tried setting padding and various other properties
with
        \override InstrumentName #'padding = #3

but nothing happens. I've also tried setting self-alignment-X to
different values but I get no change there either. I tried different
contexes before InstrumentName (Voice. Staff. Score.)... And I've tried
putting it before and after the \set Staff.instrument line... But I
can't figure out how to do this!

Lilypond 2.5.18

/Jonatan    -=( http://kymatica.com )=-