ORIGINAL: rgm762
ok i'm totaly lost and need help on cg. i know it's critical and why, guess what i want to know is are there warning signs when balancing? i.e. your putting an arf together and using all the equipment the manufacture calls for, correct size enginge/motor, servos, retracts etc etc, then when you try to balance it needs 10 oz's of weight added to the nose, you've already moved things around in the fuse but still won't balance out, when do you draw the line at adding weight and start looking at the cg? or is it a personel preferecnce? i've read on other threads where someone has added 1lb of weight to the nose or 5oz to the tail. i know this is probably covered on another thread and if someone knows which one?
First off, the CG is critical, but not much. Why?
Because it's EXACT location isn't critical at all. Not at all. What is critical is that you do an accurate job of placing it within a sensible range on the airplane for your first flight. And you need to know that if it's toward the front of the range you might need to increase your elevator throw, and if it's toward the rear you might need to lessen the elevator throw. Beyond that, it's really not very critical at all.
Accurately locate it.
Within a reliable prediction of where it ought to go.
Understand that a forward location deadens the airplane's response and an aft makes the elevator more effective.
And the first flights will be perfectly safe.