Knife edge spin is very stressful on the plane.... you can search youtube for some videos... basically, you're doing a forward spin but on the tip of the wing...as if you were in a knife edge position.
http://www.youtube.com/watch?v=DB_wM...eature=related etc

So the plane is put together.

I think I'll get scale level flight out of the 46ax... I current have 11x6 props but I think I will need a bigger prop for sure on this one.

the recommended range for the 46ax is all the way up to 12x7! has anyone tried this prop?

I was thinking of trying the following four props... what can I expect?

12x5
13x5
12x6
12x7

Hopefully someone who's tried those sizes on this engine can chime in

Thanks

I think you would prefer less prop to let the engine wind up a bit more.

For example I use 11X6 on my .55 AX

I think 11X5 or 12X4 might be better choices than the ones you listed for a 46 AX

I have a 46AX on my Big Stik 40 and mine wouldn't turn a 12x6 APC, not enough rpms. It runs great with an 11x6, and I have it currently setup with a 12x4 which I really like. I ordered a 12x5 to try next. It's a nice running engine. I had a faulty needle valve from the factory that gave me fits (air leak at the o-ring due to poor machining. Let me know how your prop testing turns out, I'm interested in seeing your results. DG

I ran 11x6 APC on it with my 4*. It was a great prop for speed and Thrust. But the Yak54 is about a pound heavier than the 4* and I have a few 11x6 props I can try.

I think I'm gonna stop by the LHS and pick up 12x4, 12x5 and 12x6 and try them all.