RE: Help with Sig 1/2A Skyray
Dont know what you are using for a motor but if it is a Cox with the tank attached the plane balances... and you dont really need to do more than make sure the nose drops when you put two fingers under the wing 3/4" back from the leading edge. CL 1/2A planes tend to fly better with the CG a little further forward than you may expect. The only time I have seen a skyray not balance was when someone locally changed the fuse over to a beam mounted engine resulting in the TD being back about an inch and a half from where it would be if firewall mounted.
Bob