In the past I have seen reference to zinc and sulphur powder being used as a rocket propellant. Although they react vigorously with each other, there is no gas produced, ZnS being a solid. So the question is: how can they possibly produce thrust?
The temperature of the reaction is such that the ZnS is vapourised - certainly a lot of white smoke is produced. I wouldn't put this propellant in a Jetex motor though! We need a woosh rather than a bang!
I did wonder if that is the case. I see ZnS sublimes at 1,185 deg. C. Yes, way too hot for our Jetex motors. There is a fellow on eBay (USA) who offers his formula for Jetex fuel substitute. It turned out to be Zn/S. He obviously knows nothing!
my name is Colin Gammans and I have recently come across this forum which has reawakened a childhood intreast in Jetex and rocket motors which we flew over the local sea shore. I am a Physicist but in recent years have been doing Electro-Chemical research and development.
I have to admit that I am not interested in the model making side of the hobby My interest has been aroused particularly by the problems associated with the supply of jetex fuel and the variability of the performance of Rapier motors. In my humble opinion :-
Dr Edward Jones seems to have done enough research to be able produce suitable propellent pellets but has dropped of the radar before production, is there anyone out there who will take up the task of production. If I can help in anyway please let me know I can probable source all the ingredients needed from my existing supply chain but would not be able to carry out the production.
I have to say |I am not surprised at the variability of the rapier motors which I would suggest comes from the difficulties of mixing the ingredients to a completely homogeneous mixture even using the equipment used for instance for mixing pigments into the base part of paints even dispersion is a problem as I know to my cost. On a cottage industry scale without ball mills or high sheer dispersion equipment it would be almost impossible.
thank you for this. Ed Jones did the fun bit with developing propellents for his 'Spadron' motor, which looked quite promising.
But the real problem, as you imply, is tooling up and production.
I might add that then fulfilling all the legislative requirements for the storage, distrubution and marketing of this pyrotechnic product is daunting indeed.
If you wish to discuss this with me 'off line' (I've been here before quite a few times) please contact me by email.