ORIGINAL: gboulton

Yes. It matters.

First, you want the weight to be on the other side of the plane's CG from the "heaviness" if you will. So, since your thread title says "nose heavy", you'd want the weight to be aft (rearward) of the CG.

Second, the FARTHER away from the CG, the LESS weight you'll need. Simplified, you can do some basic multiplication and arrive at some numbers. Multiply weight x arm (arm being length from CG), and you'll get a "moment".

For example:

Put a 2 oz weight 12" aft of the CG, and you'll have a 24 oz-in moment.
Put a 1 oz weight 24" aft of the CG, and you'll get the same 24 oz-in moment...and thus, the same change to the CG.

So...yes. To balance a nose heavy plane, put the weight rear-ward of the CG, and the farther to the rear, the less weight.

Also worth noting...sometimes simply MOVING some weight a bit will help. The math works the same:

If you have a 6oz battery 6" forward of the CG, that's a 36oz-in moment. Move it back 3", and you cut the moment in half...which would have the same effect as adding an 18 oz-in moment rearward. So, even if you don't move stuff to the other side of the CG, moving something CLOSER to the CG can have the same effect as ADDING something to the other side.