One method of balancing a plane:
Balancing your radio controlled airplane is critical to proper flight performance. When balancing a
foam electric plane, I use this method to determine the balance point by positioning the battery pack:#1 - Install everything except the battery as per the instructions
#2 - Mark the underside of the wing to locate the C/G (center of gravity) Usually, this is indicated by a distance from the leading edge of the wing
#3 - Create a balancing "jig" (I used the tips of epoxy bottles with this jig - you can use popsicle sticks, or anything similar to support the plane)
#4 - Tape the battery to the fuselage in the location as per the directions (the battery may not be "inside" the fuselage with a foam plane, just tape it to the bottom of the fuselage instead - use just enough tape to securely hold the battery pack in place - you'll be removing the tape later during the balancing process).
#5 - Place the wing on the "jig" so the plane supports touch the C/G marks under the wing (see photos below). The plane should have a support in the front & rear of the fuselage so the plane can "teeter" front to back when sitting on the jig - this helps prevent the plane from falling off the jig during the balancing process.
#6 - By removing & repositioning the battery held in place with tape, you can find the exact position for the battery so the plane will be balanced. When balanced, the plane will not be touching the fuselage supports (see photos below).
#7 - Mark the location for the battery & create its opening
Remember: ALWAYS check the balance of your plane before flying it
Also, it's usually easier to fly a plane that is a bit nose heavy than to fly a plane that's tail heavy.
