Printed at 0.2 later height. 2x shells, 16% infill...... apart from mid piece; For the Mid piece to get the upper shells to print correctly you'll need to print on 100% (no difference between 16% & 100%) Now put the shells on 0.6 if you're using a 0.4 nozzle, I know mental right??? But this gets the shells to print correctly, and the mid piece will be good and strong.