It is the flexible shaft
DIE grinder:
http://www.caswellplating.com/buffs/flexible_shaft.htm
It only has 0.5 amps, so it cannot turn a big wheel. I did put a 4" canton flannel wheel on it and it struggled with it, but I was able to get some better results. I did not use the technique of cutting in one direction and coloring in the other, although it makes sense. I was going in every direction - circles, zigzags etc.
It seems I was twiced cursed: the wrong tool and the wrong technique,
but, knowing what is wrong is half the battle!