propellant development

Hiah folks, I have a 1 stage vacuum pump VP125, but it also includes a 1/2 inch 12x12 plexiglass cover, rubber inner tube seal, vacuum gauge and release valve designed to work on a Kitchen-Aid 6 quart mixer. Works perfectly. Specs: 1/4 HP, 5 Pa, 3CFM. More than adequate for drawing gas out...

Hey guys, I'm currently into building my own motors and was wondering if anyone else out there currently uses star grains? I currently use a bates grain configuration (basically multiple toilet paper roll shapes stacked together with a slight gap between each) but I end up taking a long time to...