The first 4 grains were cast today. Each grain weighs approximately 3 kgs. In total 8 of these grains are needed for the CHIRON2 solid rocket motor.

Fig. 1. Four grains in the compression molds

The CHIRON2 rocket requires custom made casting tubes. As the kraft paper tubes of the CHIRON1 rocket may have caused the engine failure, a more solid approach was taken.

120*114 (OD/ID) aluminium tubes were reduced to approximately 117.5*114. To assure proper bonding of the sorbitol propellant, a single layer of thick kraft paper was glued into the aluminium tube.

Fig. 1. Aluminium tubes with the inner layer glued in.