The cartridge and ignition system outlined in a post a few weeks ago has in the last few weeks been manufactured, adjusted as needed and thoroughly tested. Roughly 2 cm of kanthal wire has been used to ignite the guncotton and a few layers aluminium tape has served to separate the guncotton from the particles as well as to keep the particles inside of the cartridge. We are pleased to see that the guncotton consistently ignites when a current of more than 1.8 A is sent through the wire and that the tape layers are easily broken to produce a nice plume of particles.
The picture to the left below displays the cartridge prototype filled with flour and applied aluminium tape. The other picture shows the plume achieved in one of the latest tests using about 0.1 g of guncotton (together with a beautiful old fashion variable resistor).
The next step will be to manufacture a prototype of the entire system of cartridges to be used on the FFUs. The idea is to have ten cartridges similar to the current prototype with ignitors connected both in series and parallel. We are currently testing how best to implement this and more updates are to be expected in the coming week.