If i measure my plane and wings can someone help me on the ceter of gravity i have tried the cg calculator but get stuck on the mac part of the ecuasion. Thankyou all

P.S damn no spell check lol

MAC = Mean Air Chord

What kind of plane are you working on? Most planes will be flyable with the C/B set from 25%-30% of wing chord (this is length not span). so if you have a wing that is 10 inches from leading edge to trailing edge you can safely fly it with it ballanced at 2.5 inches from leading edge.

In adition the above works on rectangular wings not tappered or delta.

Ok starting to make sense. Its a high wing trainer dont know what make could be a home built one. anyway it has a wing chord of 12 and a half inches including ailerons and 11inches excluding ailerons. Im guessing I should take the ailerons into consideration so it should be aprox 3inches from the leading edge?

of course yes it has a flat bottom and has a dihadral. Ithink thats what its called the wing tips are higher than the middle of the wing if you know what i mean lol

Yes you are describing dihedral. With your Chord length of 12.5 in devide by 4 (25%) = 3.125 inch or 3 1/8 from leading edge. This should be a safe starting point.

Thankyou Verymuch I should sleep well tonight. Thanks again everyone

Ok one more problem just come to mind. is the downthrust of my engine important on my trainer?

Likely (but not always) the CG on a trainer will be on the spar . make sure your fuel tank is completely empty when balancing. and no breazes from furnace etc. balance laterally as well by holding it with a loop of string to the prop shaft and by the tail end of the fuse(a well centered pin helps). this will make a much better flying plane good Luck

lmao thanks I love your quote OzMo

Yes.