Back in the mid-70's, John Kilsdonk, a well-known and honored CL Racing
competitor, published an article describing a basic propellor pitch
gauge. The article was published in the August, 1975, issue of Model
Aviation. This design was available commercially as the
"Prather Pitch Gauge" although that gauge is not quite the same (e.g.,
the "stations" that are defined by the slots in the base are 10mm apart
instead of .5".)
Back-issues of Model Aviation are available online at the AMA website, but to save you the trouble, here are the five pages of the article. The images have been cleaned up a bit.
Recently, a fellow modeler, John Byrne, re-discovered this old information and has gone to the trouble of creating a CAD image of the HoopTee Pitch Gauge. John has labeled this the "HoopteeToo Plans" and has created them in PDF format. You can access the PDF here, and the full-size scale and pointer here.
Much thanks to both John Kilsdonk for being the pioneer he was, and John Byrne for creating a modern-technology working illustration and design.