# Batch 2018-batch-02 # 4 grains 80mm long for 54mm cases, with 0.5 inch cores These grains were cast by college students after I did a demo batch. The simulator says we need 200g of fuel per grain, so the batch size will be 800g (plus a bit for the pan made up by re-melting previous scraps): * 65% KNO3, 520g * 35% Sorbitol, 280g * 1% red iron oxide, 8g, added after melt * 12 drops Polystep-B1, added before pour using eye dropper This formula is completely fluid with 225F indicated on the Presto Multicooker, but viscosity is noticeabley lower making for easier pouring at 250-275F. Grain fill lines 73.6mm from the bottom of the casting tube. These grains were cast on 2018-12-17. ## Results ## * Grain 1, 193.4g gross, 5.78g casting tube, 187.6g net propellant * Grain 2, 192.5g gross, 5.87g casting tube, 186.6g net propellant * Grain 3, 190.8g gross, 5.83g casting tube, 185.0g net propellant * Grain 4, 195.1g gross, 5.79g casting tube, 189.3g net propellant