Ok, I have a uproar 40 with a 46ax on it. I know that is more a sport plane then 3D but I've heard of people making the control surfaces bigger so it will hover. I can hover mine now for about 20 seconds at best then it wants to nose over. I think I'm still nose heavy though. My question is how much bigger should I make the surfaces?

I did a similar mod to a somethin extra. I added a counterbalance to the top of the rudder about 2" high and 1" to the elevators. Make sure you can get at least 45 degrees throw out of both surfaces. I didn't do anything with the ailerons except maxed out the throws. Start working the CG back slowly (so you can get used to it). And then practice, when you think you practiced enough then practice some more

I added counter balances and wingtip gates or side force generators. The coupling is terrible for knife edge If I were to make the SFG again I would add equally top and bottom. This is my first plane that I ever did tail touches on the runway with. You may want to make it more tail heavy as well, I don't recall where I had mine.

Blessings,

Jay

what can really improves is to put on a turtle deck, add a canopy and make the fuse much more taller, also SFG can be a good idea too, tall fuses and more lateral area makes the model roll better KE muuuch better and adds more rudder control, besides it will look much better!