FLYMIKE,

A properly setup plane will certainly make 3D easier and that includes thrust angles.

To check side thrust, go to at least 80% power and pull a vertical line, do not correct for anything, just let the plane slow down and watch what it does. If it's pulling to the left you need right thrust, if it's pulling to the right you need left thrust. You also want to do this into the wind, not in a crosswind and you want to make absolutely sure your wings are level before you pull vertical and you have no rudder trim in.

For up/down thrust come into the wind flying perfectly level at least 1/2 throttle. Chop the power and see what the nose does. What you want is the nose to stay where it is until the plane starts to slow. Once the plane starts to slow it will gradually lower the nose on it's own. If the plane suddenly drops the nose you have too much up thrust, if the nose suddenly raises you have too much down thrust.

Do each of the above several times.

You also want to make sure your CG is where you want it and your lateral balance is correct and the prop you have on is the one you want to use. Each of these can effect each of the above so they must be done first.

Also, while you are at it, check to make sure you elevators are moving at exactly the same speed and exactly the same throw. The easiest way I do this is to take to long and very straight sticks of balsa and glue them to spring type close pins. Now clip each one to each elevator half in the same spot on each half and have them meet just behind the rudder. Now move the elevators slowly and you will quickly see if the elevators are perfectly matched all the way through the complete travel range. Throw meters work well but this method is very quick and easy to see the results and cost little to make