The picture at the right shows an MMX downscale I built based on the Odd'l Rockets Break-Away kit.
I tried to fly it once before with an MMX engine, but it was unstable.
The big kit version flys fine, all stable flights.
In this small version I had to add nose weight.
In the picture you can see some metallic dots in the nose cone. Those are finishing nails set into the cone. This model didn't have any room for clay weight.
The newer balsa cones from Balsa Machining Service have three holes in the base of the nose cones. The holes were obviously left from some sort of centering and holding device for shaping.
Finishing nails fit perfectly in these holes and would add just the right amount of nose weight for a stable flight.
I used my wire cutters to score a line around the nail, 1/2" from the tip.
Holding with pliers, I bent it back and forth to easily break it on the score line.