Place symbol on stem

I would like to place a little arrow down symbol on a note stem (in a fixed position, much like a trem). How can I do that?

At the moment there’s no way to define custom stem decorations, though it is something we plan to add.

In the meantime, if you don’t need to use e.g. the “z on stem” tremolo, you could change its appearance to suit in Library > Music Symbols.

Thank you, @dspreadbury ! I do need Salzedo notation, and besides that I actually need to create more than one symbol.

I tried “Vertical lines”, but they position themselves either left or right of a note. Is there a way to place them right on the stem?

Can I leave a wish here? Custom stems would be awesome!
And: Why are all the Salzedo symbols grouped in “Pitched Percussion”? Wouldn’t a separate harp section be more appropriate?

As I said in my initial reply, making it possible to define custom stem decorations is something we plan for the future. There’s no way to position a line directly on the stem, which is why I suggested repurposing one of the single-stem tremolo music symbols.