We've just put up a new log entry about our Hackaday Prize project. In this one, we add lids to our hollow volume-comparison objects, and show a bit of the math behind them. (Oh, and prove that the volumes are equal!)https://hackaday.io/project/11312-3d-prints-for-teachers-of-the-visually-impaired/log/44719-putting-a-lid-on-it
