Building the (scratch) R13 (part 1)

I’ve started building the R13, an oddroc I conceived of almost a year ago. I’ve been referring to it here as RX, but forget that. I decided last year to build a smaller, less odd prototype, the Rxiiiab; I built it, flew it, painted it, declared victory, and this year I build the real thing.…

0FNC: Some further thoughts

Chris Michielssen pointed out his build of the Centuri (American Rocketeer) Finless Rocket. Somehow I missed that one! Interestingly, he says it’s stable on a B6-4 but unstable on a C6-5. I tweaked my Finless sim to get it close to what Chris built. With a B6-4 the CG is 3.284″ ahead of the (OR-computed) CP.…

0FNC: Some thoughts

I made attempts at simulations of the Arcturus, Candlestick,* and American Rocketeer Finless Rocket. Here they are along with the Rxiiiab.There was a fair bit of guesswork involved and the CG must be somewhat uncertain. The CP from OpenRocket coincides for the Arcturus with that given (presumably calculated by hand from the Barrowman equations) by…

0FNC: Some history

You don’t see a lot of finless rockets like the Rxiiiab, but they’ve been around for ages. Of course there was Centuri’s The Point, and others in a similar vein like the Odd’l Rockets Wedgie and for that matter their Birdie. But I’m thinking more of 0FNCs: Rockets with a nose cone, and a body tube for it…

Broke and confused

I’m a bit mystified as to what happened to the Big Blinka. The shock cord leader (running from the motor mount to just below the end of the booster section) broke, just above the centering ring — i.e. at a point away from the blast zone. It doesn’t look to me like it burned through,…

Building the (scratch) Rxiiiab (part 2)

So here’s a start on the 13 mm motor pod. The two BT-5/20 rings are to close the gap and align the tube while the BT-5/50 acts as a thrust plate. Here it is in the end of the BT-50 body tube. I made two cardstock shrouds (from the patterns generated by OpenRocket), picked the…

Building the (scratch) Rxiiiab (part 1)

You know things are getting bad when the number of rockets “in progress” gets into double digits. I have 8 rockets in various stages of painting waiting for me to finish them, and 1 about ready to start painting, plus the Fat Boy being assembled. But when the glue is drying and weather doesn’t permit…