Pit viper:

I don't trust the CG machine due to the ease of moving the measuring rods back and forth. Suggest you measure and mark the recommended CG location with a removable ink marker pen, and then use two short lingths of striping tape 1" or so and position it over the pen mark extending from the fuse side toward the wing tip as streight as possible. Now you should be able to position the feet of your CG machine at identical locations on both wings and visually confirm the location. Sounds like your machine is hanging up somewhere, maby the rudder. Should tip freely. Set the CG per tape location and remove from the machine. Now, use your finger tips at the tape. You should get the same results, or at least very close to the same results. Dub Jett uses two led pencils, with a larger pointed eraser. His wings are typically composit, would be a little hard on a 10 lb. balsa wing aircraft. ENJOY