Originally Posted by Valid8r
Can anyone provide a basic primer on determing CoG? With, without batteries? From where to where?
The object isn't to 'determine' CG. The object is to 'set' the CG to the proper point. Assuming that you have a basically stock SS with an EPS300 power system, that CG should be about 4-1/8 inches back from the leading edge of the wing. On the SS, close is good enough, btw.
Measure back along the center rib on the underside of the wing and make a mark where the CG should be. Then (with the battery pack mounted to the plane and using the mark you just made as a guide) pick the plane up by the underside of the wing with your fingertips on each side of the rib at CG point you just marked. Let the plane teeter-totter from your fingertips.
The plane should hang level. If it doesn't, slide the wing and/or battery pack around on the aluminum tube until it does.
That will be a good starting point. Once you become familiar with how your SS flies, you can adjust the CG forward or backward to tailor how the plane flies.
May the Force be with you.