Turn placed between notes

[Nick Payne]

See attached graphic. Quite a number of these in the score (Brahms 
Sextet Op 18). At the moment I'm creating them like so:

\version "2.17.13"

\relative f'' {
  f4.^\markup { \halign #-3.5 { \musicglyph #"scripts.turn" } } g16 a |
}

but with the value of halign hard coded, with differing note values and 
bar spacing, I have to fiddle with the value of halign each time to get 
the turn centred between the notes. Is there a more automated way of 
positioning the turn? Lilypond seems to assume that turns should be 
placed directly above a note, but that is often not the case.

Nick

Selection_003.png
Description: PNG image