What did you do rocket wise today?

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I had to teach a night class tonight but had just enough time to cut 4x Super Bertha fins from 2mm plywood before putting my own kids to bed. First time I tried to cut two stacked sheets at once with good success... These fins are pretty large so use up a ton of my 200x300mm material (particularly since I am planning a Booster Super Big Bertha and a Super Baby Bertha -- that's 12 fins sheesh). I want to try to launch a Booster Super Baby Bertha just to be somewhat unique in the Bertha space!!!

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Maybe I need to go back and double check my sim, these fins seem kinda small:
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Well, maybe not once the Kraken tubes are on. ;)
Finlets are for thrust transfer since you don't get TTW from tube fins. Should have just made a centering ring/thrust plate, but I didn't think of it. It's all probably overkill anyway, but that's just how I build right now.

Going to start out single deploy, so I drilled and CA'd the rivet holes that will attach the coupler to the upper half. Will use the same holes and rivets on the DD ebay whenever I get to that. Electronics intimidate me a lot.

Up next is sanding the tube fins and sealing their edges as well as external fillets on my Black Fly. I also need a name for this tube fin rocket; Cuttlefish, maybe? It's basically a long Kraken with 6 fins.
 
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So I was kicking around an idea if picking up some38mm cases... to do this, I have to shop the reloads I might wish to buy. My gauge on pricing has always been to look for the Aerotech J350 reload, a favorite of mine for 20+ years. So what did I do rocketry wise today? I sticker-shocked when I saw that the J350 reload now retails for $81++ bux!!! For 1.8 seconds of zoom!
 
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So I was kicking around an idea if picking up some38mm cases... to do this, I have to shop the reloads I might wish to buy. My gauge on pricing has always been to look for the Aerotech J350 reload, a favorite of mine for 20+ years. So what did I do rocketry wise today? I sticker-shocked when I saw that the J350 reload now retails for $81++ bux!!! For 1.8 seconds of zoom!
's'ok, a couple decades ago, someone named their rocket "75 Bucks A Second" ;)
 
Just "Z-Folded" and taped the first of the OneBadHawk Kevlar shock cords for the Level 3. This is the 30 foot aft one which is why I triple taped the folds... as much energy "bleed-off" as possible.

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Did one pair of external fillets on my Black Fly. Seemed to go pretty well. For some reason I thought I could do two pairs on one batch of rocketpoxy and ended up wasting a bunch. Any tips on how to get one pair to set enough so that I can turn the rocket and do another pair without the first sagging and without the remaining epoxy getting too hard? I want to say a heat gun or hair dryer is the key, but I don't remember.
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I also lightly sanded the edges of half my tube fins and sealed them with CA. I think I might have to start buying BSI super gold, but damn that's expensive.
 
Did one pair of external fillets on my Black Fly. Seemed to go pretty well. For some reason I thought I could do two pairs on one batch of rocketpoxy and ended up wasting a bunch. Any tips on how to get one pair to set enough so that I can turn the rocket and do another pair without the first sagging and without the remaining epoxy getting too hard? I want to say a heat gun or hair dryer is the key, but I don't remember.
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I also lightly sanded the edges of half my tube fins and sealed them with CA. I think I might have to start buying BSI super gold, but damn that's expensive.
Put the excess epoxy into the freezer after doing the first set. After it has cured then thaw the remaining epoxy and do the second set of fins.
 
Just received a gallon of West System 105/206. My existing batch is getting low and well past its use-by date. Back to building rockets!

For the remaining old batch I am tempted to mix it up in a paint tin in the backyard. One reasonably large batch. Could be a good spectator sport, especially with temperatures in the 90's.
 
Since it was errand day I didn't do much rocketing. But I did make a 2 stage spool. The dowels should keep the 2 spools together. I hope. The hole in the middle was almost a perfect fit for a C6-0. Just a couple of wraps of tape and they are in there snug. The top motor protrudes slightly into the bottom spool. I'll entertain the crowds at the next launch with it.20220127_211243[1863].jpg
 
Laid out and counted parts for my Eggfinder receiver. I'm planning to start assembling it this weekend.

Also ordered batteries (thanks, @heada and @cerving), a charger, and some JST connectors.

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I'm hoping (and reasonably sure) that your hands are steadier than mine. My hands shake when I concentrate on fine work. I believe that it's Belle's palsy as my grandfather had it. I've sent a few SMT components to God knows where. It steadies up a little as I work though. It helps to brace my hand against something stationary.
Jim
 
Started work on an Estes Ventris (while I'm waiting on parts from eRockets). I built up the engine mount tube and sanded the plywood fins. Heading to the store tonight for some more Fabri-Tac and should finish up over the weekend.
 
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