The mandrel can be perfectly einrammen in a harder ground, or if you previously briefly veers off the clamping screw, wrap it with a large rubber mallet. How, however, may set a miserable product image, is beyond me. The upper part is still fairly recognizable, down one could however think it's just a round steel, the one einrammt. In a second view you could see that there is a stronger along folded sheet that tapers down.