Simple...exactly...that's why you can forget all about the fancy string trick and do your lateral balancing dynamically -- while the airframe is under a load.

Have you flight trimmed your plane yet? About the forth step is to laterally balance by taking the plane up about 500 feet, going into an idle dive straight down, and pulling out after about 2 seconds, if a wing is low, that is the heavier wing, add weight to the other side...even with wings that are the same physical weight, there could be other issues that cause your plane to be out of "balance."

Do it Peter Goldsmith's way, JR Team Leader, TOC competitor, he is the man! Just read your Model Aviation - Scale Aerobatics Article in Feb and Apr.

There's also a helpful thread on this here in RCU...just type in "Peter Goldsmith" in the search box, look at the one that is titled "Thanks to Peter Goldsmith."