This is a classical construction, if you search for “pinwheel”, you’ll find at least two more in the Ravelry database, by Carolyn Christmas and Elisabeth Ann White.

Warning: The pattern is in German, as is the forum it is posted in. If you are a speaker of German, feel free to apply there. If you don’t understand German, don’t bother; it is probably easier to make up your own star pattern then to fiddle with the translation. :)

Please note that “free” does not mean “available online by a click”. You have to apply to get into the forum.