Oh no you don't, young man. Not until you finish your dinne... er, pencil.
Build thread: Blackfish
- Thread starter neil_w
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Final weight without shock cord and parachute comes out at 3.45 oz, a bit above model at 3.05 oz. Not too bad. CG, however, comes out somewhat further back at 19.5" vs. 17". I'm going to have to start including more fudge factor in my OR models, because there's clearly a lot more weight in the rear than I have planned. I'll need to recheck with shock cord and parachute, but it looks like I might need about 1/2 oz or hanging from the nose to stabilize this.
What I should really do is refrain from installing the eyelet in the nose cone until I do this measurement; easy to add weight *before* the eyelet, harder afterwards. I'll figure something out.
A JLCR would *almost* be enough, but probably not quite, and I can't assume I'll always use it. But in theory it should fit.
What I should really do is refrain from installing the eyelet in the nose cone until I do this measurement; easy to add weight *before* the eyelet, harder afterwards. I'll figure something out.
A JLCR would *almost* be enough, but probably not quite, and I can't assume I'll always use it. But in theory it should fit.
Once the shock cord and parachute are in, try adding a mass object to the model that's the right mass, then shift it around to find where it goes to get the accurate CG. That should give a clue as to where the extra weight is in the build. Just a clue, but maybe worth it.
My guess: it's all those decals.
My guess: it's all those decals.
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Wow, there’s a REAL blackfish!
https://news.google.com/articles/CA...wL2ICzCckocDMIOHqQY?hl=en-US&gl=US&ceid=US:en
https://news.google.com/articles/CA...wL2ICzCckocDMIOHqQY?hl=en-US&gl=US&ceid=US:en
Ladies and gentlemen, I present to you the Pacific blackdragon (another good rocket name):
Sleep tight.
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Gonna need a lot of nose weight......
To get to sleep?
Nice work Neil, great paint scheme and finish!
Neil B.
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Hey Neil,
Somehow I lost track of this build thread, sorry.
Anyhoot, your glam shots look AMAZING! Well done sir.
Somehow I lost track of this build thread, sorry.
Anyhoot, your glam shots look AMAZING! Well done sir.
Thanks. I really look forward to flying this one. Of course, right now I would be thrilled to fly *anything*. 
...and now, a mere 13 months after completion, Blackfish has flown. Conditions dictates an extremely conservative flight, so I shoved a C11-5 in there and hoped for about 350' according to the sim. Perfect straight ascent, late deployment (as expected; a C11-3 would probably have been a bit better) and clean recovery with no damage. I look forward to flying this one with bigger engines in the future.
View attachment bf_launch.mov
View attachment bf_launch.mov
Yup, 5 maidens, five videos posted.
Under normal circumstances that would be an almost unbearable amount of puckering, but I was flying so low I really didn’t have that much fear, at least after the Blackfish flight.
Successful maidens are always the most satisfying flights for me. Five in one day left me feeling mighty good, I ain’t lyin’.
Did you remove the BT5 tube before the CWF application?
Nope, the entire pod assembly was covered, including the body tube.
