Gary...are you referring to the "old" paddle blade Graupners or the new "G-Sonic" (APC like) design?

I have used 2 blade "old" ones with quite good results, so I'm interested in the "G-Sonic" line. I'm not a huge fan of 3 blade props, tho I did stumble onto several carbon ones that work well on my PA .51. The next prop to test on it, however is a CF 2 blade "Magic" from Randy.

One of the Dutch fliers recommended one of the "old" 3 bladers (10-7?) for the ST .46. I got one of the props, but haven't run the (T&L) engine yet, and might just sell it to help pay for another PA.  Steve

If it looks vaguely like a Kaysun 6-3, that's the Old Graupner (OG). If it strongly resembles an APC on crack, it's the new "G-Sonic" Graupner. None are cheap, but they're good stuff for a plastic prop, IF they have a size that you can use. The old Graupner, 9-4 is a good prop for .25LA's and probably a .20FP. I only have one, and got it used at a club Swap Meet. My Ex-Dirt (GMA cylinder timing) ST G.51 liked an 11-6 OG, or an APC 12-5 trimmed to 11.5", with the tips restored to near stock shape, which was a LOT more work. Don McClave told me that when he used a ST .60, he used an OG 12-6 on it. That said, there are some Thunder Tiger Cyclone props that are also excellent and about 25% the price.  http://cdn5.hobby-lobby.com/images_products/386_small.jpg

Just looked at the Hobby-Lobby website and didn't find the G-Sonic Graupners, or 3 bladers of either type. Most are too high pitched to suit piped or "wet 2" type engines. APC and also the 11 x 4.5 TT Cyclones are da bomb there.  Steve