5_spot,

Not picking on you at all. Listing a prop or two for various engines as a "place to start" is one thing, and can be useful. For that purpose, you can just check the engine instructions, or just list one prop for each size as a starter.

But the problem with charts and such is they tend to be interperted by beginners as "listed props are ok, not listed props are not ok".

When what a beginner should be learning is that our engines can actually run with a rather wide variety of prop sizes, and you want to pick your prop to match your engine (not just displacement/size, but the make and model), airframe, and the way you expect to fly it. It sounds complicated, but it's actually not a big deal.