Larry, sure sounds like aft CG to me. The Wonder has a very narrow CG range - you don't want to be off in either direction. Don't use your fingertips to balance; that's not accurate enough. Build a little balance stand like it shows in the manual.

Also, I'm wondering if you are actually throwing the model to launch. Your post makes it sound like you're just letting it go. Mike's got it right - get somebody else to launch those first couple of flights until you get used to it.

And Cobra99 - No, it's not designed with sheet metal in the sides. There must be a story behind that!