The patience of a Jedi. Keeping your mind on where you are at, what you are doing.Clear Coat...
As a side note I used a Sharpie to write THUNK on the rocket. I'd read here that clearcoat over a Sharpie will lead to the Sharpie text bleeding / running. That didn't happen. I made sure to put a light coat of clear over the area of the rocket with the text first, then waited an hour and applied a 2nd coat.
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@lakeroadster's Thunk gave me an inspiration. I'm making a similar rocket. It's a 29mm motor tube. 4 fins top and bottom. 24" long. I have a 3" x 48" mortar tube that I fly a rocket that looks like a 60mm mortar bomb out of. I have sized the fins to fit inside the tube. I have the fins on and the nose cone has a load of BB's and epoxy. If needed I'll add more weight below the nose cone. Now I need to pick a motor. G80-13 maybe. Probably not a good choice for a first flight. I'll pick a motor that will keep the rocket in sight. I think that by the time the rocket clears the tube it will be spinning like a top. That last line made me think, when was the last time I played with a top. Easy answer. A long time ago. Late 60's I think. The mind is amazing. I can picture the top in my mind. It was wood with a metal tip. Red I think. But I can't remember what I did last week. When was the last time you all played with a top? I know. I'm rambling.
Wow. That's fast. I had no idea it would spin that fast. That's as fast as a bullet. I'm going to paint the fins in a white and black roll pattern. It will just be a blur.Sounds like a fun project.
Open Rocket shows a roll rate of 23 rev/sec when THUNK! clears the silo. Maximum rev's is at apogee, and is a bit over 45 rev/sec. That's a lot of RPM's... 45 rev/sec = 2700 RPM. At ejection the roll rate is down to 3.7 rev/sec. = 222 RPM. I'm wondering just what is going to happen when the chute deploys? I have swivels and a long Kevlar chord and an elastic chord too.
Weather permitting, I hope to get THUNK! launched this week.
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Wow. That's fast. I had no idea it would spin that fast. That's as fast as a bullet. I'm going to paint the fins in a white and black roll pattern. It will just be a blur.
I got seconds and minutes mixed up. I thought it was 2700 rev. per sec. My bad.FWIW... rpms vary depending on rifling and muzzle velocity but a bullet spins at over 100,000 rpm's.
I doubt that these rockets will actually spin 2700 rpm. They aren't balanced, so that will limit the rev's. With any luck I'll get some video / photos of THUNK! exiting the silo so we can get a visual.
Hoping to launch Tuesday or Wednesday.
Open Rocket showed a 511 ft. apogee. It seems like it bettered that?Nice flight (My D-powered rockets never get up that high). Surprised no "thunk" though
Should I launch Thunk! again, but with the GDS ports blocked with some aluminized tape, just to see if the stability was truly from GDS, and not from it spinning?
What do you think folks? Is it worth risking Thunk! as a possible sacrifice to The Rocket Stability Gods?
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