Originally Posted by
VincentJ
Not stupid Robert. Theoretically, you are correct. The amount of weight that you add should bring the control surface to the neutral position when hinged, however the weight that I have added is per the spec on the plans. These don't however get the elevators neutral, more weight is needed which I am not adding...
You're an evil man there David!
I bought 1/2 pound of #7 lead shot several years ago to solve problems like I see others having balancing control surfaces and to stop eating planes to flutter.
What I would do, since we already know the surface is 'tail heavy' is leave a 1/8" slot open on the counterbalance beam to be filled in after the rest of the sheeting and sanding is done. Then put the hinges in temporarily and fix the hole with more weight and seal it. To do that, mix up some epoxy and dribble it in and then put shoot into the slot until the surface was level. Oh, another 'trick' is to estimate the needed weight before you start by testing.
The issue here is that the lower the 'out of balance' the less the chance for servo destroying flutter to set in. I really really hate it when flutter eats something I have spent hours building, and it HAS happened! For some nasty reason it always seems to bite me on the elevator circuit.
One lasted a couple of months and another really good scale job went in on the maiden for flutter...everyone there heard it.