Friday, March 19, 2010
Work has started on the 2 inch, 29mm Drago kit. Here is the motor mount assembly, with the top centering ring in place. A notch was cut out of the ring to allow the kevlar shock cord (thinner than in the 38mm thunderbolt) to pass down the side of the motor mount. Everything was tacked in place using thin CA. Sadly, the ring somehow wound up a bit crooked. I will now have to sand, crack, or dissolve the CA and redo it. Once it looks good enough, everything will get a thick layer of epoxy (maybe JB weld rather than 30 minute due to the heat exposure?) I plan to slide this motor mount into the rocket, and then CA the fins in place around it. The lower ring will be kept out so that the fins can be reinforced with fillets both inside and out of the rocket, per the technique used in builds particularly in the late 90s. The idea is to get a really solid fin mount so that this rocket can handle some serious performance and high speed recoveries.
This kit is very bare bones - there is no motor retainer, that is common, but there are not even any launch lugs! It is clear how they can keep the costs down, and someone with the basic experience needed should be able to take advantage of that.