Have done this! Works great if you do it right. You have to heat hot, then pull the nib out of the handle if you entend to reuse the handle. Squeeze fast and firm with a spacer in the V. Preferably the sharp side of an Xacto blade, as the Staedtler nibs come to a sharp V where the Speedballs are round in the troff. They do tend to crack a bit easier than the Speedball nibs, but it is posible to do and has been done before. The kicker is that if you do crack them they are still closer to being usable than the Speedball nibs. I think if you crack a Speedball you might as well toss it in the trash.