I came across a pretty exciting explanation of how to weave pinwheels on a rigid heddle loom. Many thanks to Jeen who took the time to explain how it works.
Loom: 20" Ashford Knitter's Loom
Reed: 7.5 dpi
Yarn: worsted weight Malabrigo Rios in Marte and Island Yarn River in Blood Orange.
I warped 9 groupings of 8 strands on the loom. With draw in on the loom, the scarf is currently somewhere just over 8 inches wide and 72 inches long.
Like others have said, this is not a fast weave. But it is a really fun project and I don't mind that it is not fast. I am a bit impatient to get it off the loom and washed to see how it looks finished. About 25 more inches to go!