speedracerntrixie

I knew you were not the one with a problem.
I was more concerned with something I read about the gap changing.
I can only think of the gap as the distance from the rear of the prop to the front of the engine cowling.

Less than 0.004 inch change or even up to 0.010 change is negligeable but not everyone apparently think so.

In fact a gap change of 1/16" (0.0625") or even 1/8" (0.125") while detectable by eye would not change anything about the performance of the model.

For newbees ___
Some design specify some side thrust and some up/down thrust and often these are built into the firewall structure. These orientations are aimed at obtaining some model behavior desired by the designer(s).

Many models do not use any side, up or down thrust and fly beautifully.
It is difficult to really justify their necessity.

One of their purpose is to aim the thrust line of action in relation to the CG and exert some influence with variations of power settings. They are a compromise and would be optimum for only one power setting.

I am NOT saying they are useless.
Some modelers recommend some flight pattern to determine the required amounts.
Their usefulness are mainly for contesters that have to fly precice maneuvers, precice flight patterns.

For the average Joe (like me) it does not make much difference.
I am quite happy with a well balanced model, one that will glide on its own in case of engine or control failure, and has the best chance of landing like the old free flight models.

Enjoy your flying.

Zor