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Basket Case 2 - 3D Printing + a K535 = awesome

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BABAR

Builds Rockets for NASA
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Curious. From a stability and aerodynamics standpoint why not just mount it higher up? Puts CP a bit higher but also moves up CG. Not sure which wins.
 

BABAR

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I tape keychain cameras on LPR rockets routinely with no shrouds, stick them as far forward as possible on the body tube. No stability problems so long as motor can handle the mass. Then again, I don't approach Mach ;)
 

neil_w

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If I'm interpreting the drawings correctly, the camera will be pointing down just above the tail of the rocket. I'm trying to think if I've seen in-flight video with that sort of camera positioning. Curious to to see how it will look.

I can appreciate the desire not to have the camera all the way at the top of the rocket, when half the video is just a static picture of body tube. I do think it's nice to be able to see the fins, at least for the occasions when they flutter which is pretty wild (of course we're normally hoping for no flutter).

Also will be interesting to see how it looks at launch, when the camera is extremely close to the motor exhaust. Once the rocket gets up to speed, and especially during coast, I would expect a very nice, mostly unobstructed view.
 

Dustin Lobner

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Just saw the various post here...wasn't notified for whatever reason.

Yes, the plan is for the camera to be down near the bottom for a less obstructed view down...I'm hoping that the fins will basically "frame" the corners of the image. I'm hoping for less tube in the frame.

I looked at it a bit last night, I believe I'll be able to put a shield of some sort that will be removed by the airstream and functionally act as a "tear away".
 

Dustin Lobner

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Made a purchase last night for this - I've been running the Eggtimers on 9V batteries, exactly as Cris tells you not to like 50 times in the manual. It's worked, but exactly as he described the Wifi is kinda flaky at that point. So, switching over to 2S Lipo as recommended.

I purchased 1S batteries and will run 2 in series. BetaFPV has a really neat battery that is in a long/skinny form factor that works really well for this rocket's av bay. https://betafpv.com/collections/batt-1s/products/bt2-0-450mah-1s-30c-battery-4pcs

They have 260, 300, and 450 mAh options. I'm going to go with 450s for the computers (one set of batteries for each computer) and 300's for the deployment channels (for those who haven't worked with Eggtimers, you have the option of powering the computer with one battery and firing the charges with another battery, so as not to brown out the computer when firing the charge).

Absolutely awesome little thing, they actually sell 2S pigtails, already wired up for running 2 of these batteries in series. https://betafpv.com/products/2s-whoop-cable-pigtail-bt-2-0

Printed the first take on the "pod", got some changes to make for sure...the "tunnel" that the camera resides in is too deep, so the whole point of putting it near the bottom for a better view is moot with the current design. Also, after feeling it, I'm sure I can make it shorter (protrude less into the airstream) without messing up the structural integrity, so going to do that. Also think there's room to "sink" the battery and camera into the side of the fincan and make the pod shorter...which seems like a great use of 3D printing (to make something that while otherwise possible is a lot more difficult) but I'd be worried about the strength. Maybe. The way the fincan is designed, the bottom 8" or so carries all the load (the tube doesn't go all the way to the bottom), so I'd be asking a lot of the 3d printed material. Things to think about on a cold Saturday in Wisconsin.

...Making progress on both the L3 and this one at the same time. Crazy.
 
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