Welcome to the forum!
1) You can get “automatical” stemlets as a “global” option for all the measures in the entire document:
Document menu > Document Options > Beams
where you can find the options
- Extend Beams Over Rests
- Extend Secondary Beams Over Rests
- Display Half-Stems for Beamed Rests
The term “Half-Stems” means stemlets.
The length is set “globally” in
Document menu > Document Options > Stems
where you can find the option
- Half-Stem Length
Sternie wrote:I have to notate a passage that would be read more easily with stemlets …
2) From your description it sounds like you only need the stemlets in a specific passage, not in the entire document, right?
To do so,
- select “Display Half-Stems for Beamed Rests”,
- set the “Half-Stem Length” to zero,
- where needed, add a custom stemlet with the Special Tools Tool sub-tool Custom Stem Tool.
You will have to create the custom stem in the Shape Designer.
When you have created the shape with the custom stem, you can use that custom stem over and over whereever you need it.
If you have a gazillion measures with the same {custom stemming}, consider creating one measure with the {custom stemming}, and using the Copy Filter to copy only your stem alterations to all the other measures.
Hint for the Shape Designer:
In the Shape Designer you can use the sub-tool Selection Tool to select a line.
A handle will appear on both ends.
When a handle is selected, you can nudge it with the arrow keys.
Hint for precision layout:
The numerical values are easier to work with if you choose small Measurement Units, like Points or EVPUs.