UPDATE 20170907: Due to the KNER propellant misbehaving during casting, I opted not to invest any resources in this KILO 12G KNER project anymore. What I noticed during casting KNER in the casting tube is that the solid KN particles settled towards the bottom of the grain. Leaving 25mm of plain ER at the top. With the normal
Final thoughts on the CATO / overpressurization of the KILO 12G KNSB motor at the LRE 2017 launch: The motor had a very conservative port-to-throat area ratio of 1.5 to prevent velocity based erosive burning. This resulted in a higher than necessary, Knaverage of 700 and thus higher Maximum Expected Operating Pressure (MEOP). Mass flux based erosive burning. Little has been described about
“We had a bad day”. This pretty much sums up our launch day at LRE 2017. First LD’s CHIRON 3 rocket overpressurized in a spectacular way, taking out the upper 2/3rd of the launch rail. A makeshift launch rail was made and the GIGA was launched from the remaining 2,5m lower section. The GIGA rocket suffered the
The GIGA rocket has been designed as a true minimum diameter rocket with fin brackets mounted directly onto the casing. This is not a particular KISS approach but rather a result from the “sustainer ready” requirement. Alternatives considered were: Welded aluminium fincan. However due to the lack of availability of matching off-the-shelf materials (it is
After some struggles with the high L/D ratio EDPM liner I managed to find an approach which worked well both inserting the liner into the casing as wells as inserting the grains into the liner. Below sequence seemed to work best: Talc both the casing and liner (in & out), remove excess talc. Insert both Full
Boring post but to be used as personal reference Liner dimensions:1629 x 300mm. Width of liner: In general the liner is constructed with a 20% overlap. Hence: pi x ID of the casing x 1,2 = 301mm = approximate 300mm wide. Length of liner: Depending on chamber length but chamber length usually is grain stack
Need a good reason to thoroughly clean your lathe? Try machining some graphite. A good shop vacuum cleaner such as a wet /dry Karcher helped a lot in keeping the mess to a minimum. However it showed over time that it was unavoidable that, after machining a full graphite nozzle, the entire lathe was covered in graphite particles. I had
One week, one part. The nozzle retainer will hold the full graphite nozzle in place. It is a variation on the simplest form of a retaining ring as used earlier on the KILO 6G motor. The variation consists of: the nozzle retainer has a divergent section where it lengthens the actual divergent section of the
Finished the casing today. It is 1780mm long and will hold 12 BATES grains. Important factor in long rockets is that all parts being properly aligned. To facilitate this all the tubes (casing, airframe & nose cone) rest on square faces. As I didn’t want to rely on the squareness of the band saw cut I had
Finished the combined retainer ring / coupler for the KILO 12G “lite” motor. The coupler was made from 80x5mm tube and almost a direct fit into the 86x3mm casing. It is a bit beefy. However lets first see how she copes with the 96bar MEOP and the countersinking of the 86x3mm casing which will probably extend into the retaining ring / coupler