Neil_W's half-baked design thread

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I could imagine doing it with 3D-printed curvy tube, but not with little pieces of BT5. They would also tend to obscure the view of the ball somewhat.

Ping pong ball diameter 40 mm
Ping Pong Balls. Table Tennis | Ping pong balls are spherical polymer balls fabricated specifically for the sport. Established under international rules at a diameter of 1.57” | 40 mm

BT-5 is about 14 mm outside diameter.
You need three tubes for effective cage, add a couple mm for freedom of ball to rotate if needed.

14 + 2 + 40 + 2 + 14 = 72 mm

Not that big, really
 

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Decorating the ball is already a vexing problem here, now you'd have to add the requirement that it be translucent, which would probably dictate clear decal paper. How do you cover a ball with decals?
Two ideas

1. Easter Egg Dye?

2. @kuririn ’s apogee post requoted on last page post 1,171.
 
It's pretty obvious that a lot more can be done with Open Rocket than I'm capable of. I've barely scratched the surface. Neil seems to be the Yoda of Open Rocket. I've got a lot more learning to do.
Just experiment, and ask questions when needed. If there are any designs for which you want to see the file to see how something was done, just ask. Nothing here is proprietary. Likewise, you can learn a lot from K'Tesh's files as well (we've given each other ideas over the years).

One important thing to keep in mind is that there are things you can do *visually* in OR that won't simulate properly. My initial goal, for the purposes of this thread, is to create and visualize a design. I use OR for this because (a) then the design can be easily adjusted to a "sim-friendly" version in OR, and (b) I lack the CAD chops to do it any other way.

So my designs here typically have some elements that don't simulate, and I need to deal with that when trying to actually assess stability and motor selection. I don't, however, include anything that wouldn't be considered part of the *design*. If you look at K'Tesh's files you'll see he has modeled fine bits like motor hooks or retainers, and other things. They look good but must be removed to get a working simulation of the design.

I do have one secret weapon: I'm using an alpha build of the next OR version, which has some additional capabilities that are quite useful.
Here's an idea that I've been working on, but can't seem to get it to work. Even without a motor, CP is ahead of CG. Neil's would actually fly.
View attachment 423834

You will find that, in general, designs like that are almost impossible to get to be stable without a monstrous amount of nose weight. There's a reason we put the fins in the back. :) This is often a limiting factor in doing sci-fi designs, because ships that are designed to fly in space don't need rear-mounted fins... or any fins at all for that matter. Many compromises must be made to get the rocket to both look like you want, and be adequately fin-stabilized to fly in the atmosphere.

That's just part of the challenge. :) Keep experimenting!
 
Decorating the ball is already a vexing problem here, now you'd have to add the requirement that it be translucent, which would probably dictate clear decal paper. How do you cover a ball with decals?

My first thought was that epoxy tie-die method in the Apogee newsletter. But that would probably not be very transparent. (or maybe???) EDIT: BABAR beat me while I was trying to distinguish my tea from the keyboard.

Now that's a whole lot more interesting. I had a similar thought for PDII, although the inner core tube was essentially minimum size so there'd be no place to put LEDs inside. This one would have room inside the ball.

Unfortunately, I have zero prospects for attending a night launch, so if I lit a rocket like this it would purely be for my own amusement, not that there's anything wrong with that.

Totally cool, even without a night/dusk launch.
 
2. @kuririn ’s apogee post requoted on last page post 1,171.
Holy crap that is incredible. There's a 0.0% chance that I'd ever do something like that in my basement, but truly that is magnificent.

It would indeed be great for the plasma ball. If anyone wants to do up a ping pong ball like that and send it to my I'll take it. ;)
 
Holy crap that is incredible. There's a 0.0% chance that I'd ever do something like that in my basement, but truly that is magnificent.

It would indeed be great for the plasma ball. If anyone wants to do up a ping pong ball like that and send it to my I'll take it. ;)
I think that’s how God made Jupiter!
 
OK, I definitely need to read that article. I'm many issues behind, but this has just jumped the queue.

Inside a ping pong ball, if you run a BT-5 for ejection gas and a BT-5 to BT-50 centering ring for the forward penetration, you could run wires through holes in the CR to LEDs surrounding the BT-5 inside the ball. Continue the BT-5 about half way up the main BT-55 to another centering ring; the parachute goes above that, and you've got a "dry" compartment below it for the electronics. Snug couplers in both tubes in the middle of the dry compartment would provide access.

Surely there are translucent paints one could brush onto a ping pong ball. If the light inside is from color changing LEDs it would be all the more awesome. For that matter, if you could manage several color changing LEDs, out of sync and scattered around the ball, then you wouldn't want to paint it at all.

To quote Dr. Frankenstein the younger, "It! Could! Wooork!!!"
 
To quote Dr. Frankenstein the younger, "It! Could! Wooork!!!"
I have some little jack-o-lantern lights that have changing colors, could theoretically dissect one and repurpose. Without paint, though it'd look crappy in the daytime. Painting challenge would be getting a good plasma design onto it, so it looks good even without the lighting.
 
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This design absolutely vexes me. I feel like there's a great design in there trying to get out, but I can't find it. Never mind the paint in the following images; they're just to show enough contrast between the important bits.

This experiment adds an enlarged front section where the windows would go, common to sci-fi starship designs.
1594345075077.png
Maybe great decor could save it, but it's not really working for me. I mean, it's "OK", but feels like it's missing something. Maybe better with canards?
1594345516555.png
I dunno, doesn't feel very inspired. Here is without the enlarged front section, also stretched a bit:
1594346020488.png

Sleeker, I guess? Here's what I started with originally:
1594345816017.png
I got rid of the pods on the vertical stabs because they make no sense if the plasma core is the primary drive. Also too busy. Likewise, got rid of the forward core because it also doesn't seem to make much sense, although it looks kind of good. The wings are somewhat larger on the newer design due to the need to accommodate the much larger plasma ball core.

Feedback welcome. I feel like these are *decent*, but I'm having trouble staying objective here.
 
I really like the plasma core part of the design. I think it seems a little incongruent with the styles of the fins, though. Just thinking out loud, what about either one of these approaches:
  • Mirror the swoopy shape of the plasma core in the fins somehow. Either by using the same swoops, but larger, or just similarly swooped.
  • Merge the plasma core and fins into one and the same. How big would they need to be to provide stability to the rocket?
 
Couple options.

First, and more within the box, stop trying to put the ball in the tail or the middle. That puppy is radioactive, keep it up near the nose, generating ions or electricity or tachyons or whatever. Why up front? Because it powers the weapons or sensor array in front of the ship. On a more practical level, allows you to put your batteries and LEDS with all their weight up front. Can run your support through the middle of the ball, or a small external cage. You can go Wild with the fins.

Second is the Star plasma Accelerator/Transporter

Stick this upfront with a launch lug and chute, Pop Fly style,

https://glowproducts.com/us/light-up-flashing-bouncy-balls
Again, this gives you weight up front, doesn’t interfere with ejection charge. In fact, you can go really wild with your rear fin design because you can go rear eject (glowing ball nose falls off and pulls out its own chute.). Oh wait, now I got the name——- “Falling Star”
 
If Neil is the Yoda of OR then K'Tesh is Palpatine. But less evil. As far as we know. ;)

I didn't cut any deals, and I'm not sure I'm overly thrilled about the Palpatine reference (evil?). I worked hard at learning my skills despite obsticles, and share them freely with others. I think I'd be more like Homer Hickam. ;)
 
I like the pods on the fins, but you're right that they don't make sense. They also feel very derivative of something I can't put my finger on.

The forward core wasn't so good in the original, but it might be good to have a second core, identical to the first and only a little bit forward of it. Because one core just doesn't produce enough power for this beast, but in spaceship design you would want to keep all of the core equipment in a single area rather than having to build up all the required structures twice.

I like the expanded front. Maybe add steering thrusters, small guns, big gun ports, and launch bays; you did start talking about this as the mother ship, after all.

Star Plasma Accelerator/Transporter
Oh, now, let's not get into a SPAT here.
 
Couple options.

First, and more within the box, stop trying to put the ball in the tail or the middle. That puppy is radioactive, keep it up near the nose, generating ions or electricity or tachyons or whatever. Why up front? Because it powers the weapons or sensor array in front of the ship. On a more practical level, allows you to put your batteries and LEDS with all their weight up front. Can run your support through the middle of the ball, or a small external cage. You can go Wild with the fins.

Second is the Star plasma Accelerator/Transporter

Stick this upfront with a launch lug and chute, Pop Fly style,

https://glowproducts.com/us/light-up-flashing-bouncy-balls
Again, this gives you weight up front, doesn’t interfere with ejection charge. In fact, you can go really wild with your rear fin design because you can go rear eject (glowing ball nose falls off and pulls out its own chute.). Oh wait, now I got the name——- “Falling Star”
Okay, the bouncy LED balls I suggested may not be the best option. I read the description

The LED bouncy balls are impact activated and once bounced will flash up to 20 seconds, but just bounce it again to re-set the timer. Keep on bouncing the light up bouncy ball and it will keep flashing!

So the light only activated on impact. This would not be optimal for your plasma ball (also for parachutes and streamers, but that’s a different issue.....)

But some kind of LED lit ball is likely possible.
 
I like post 1192 as far as fin/cage proportions. The increased payload diameter from this page gives it extra gravitas too.

Much more than that and you've left fiddly bits behond and gotten into over complication territory
 
(that's also a 55 mm ping pong ball):
Around here we call that a bambucha ping pong ball. 😄
(Remember when you were a kid playing with your marble set? The unusually large marble is called the bambucha. Now it means anything big. Synonyms: ginormous, humongous.)
 
The Aurora's ringtail makes it look 1) not so much like this, and 2) like you probably designed that one too. ;)

I do like the containment ribs doubling as the fins. Since space vehicles don't benefit from fins the way atmospheric vehicles do, it's nice to incorporate features that serve as fins but make sense for some other reason (like plasma containment).

For the double core version in my head, it would be something vaguely along the lines below, using your far greater curviness skills.
1594400810333.png
 
If you are going to put a BALL on a rocket, you need to show it off.
 

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The Aurora's ringtail makes it look 1) not so much like this, and 2) like you probably designed that one too. ;)
When I first saw that one:
1594401339001.png
I was *going* to say "looks like something i would design", but then decided that was a bit presumptuous and changed my wording. But the sentiment remains. :)

For the double core version in my head, it would be something vaguely along the lines below, using your far greater curviness skills.
I'll see if I can work up a model of that, see what it looks like. Probably go back to 40mm ping pong balls if there will be two of them.
 
Your design, obviously. For myself, I haven't left behind the notion of giving the impression of bigness by actually making it big. Like a BT-60 (41.6 mm O.D.) with a pair of 55 mm ba... ahem.
 
Your design, obviously. For myself, I haven't left behind the notion of giving the impression of bigness by actually making it big. Like a BT-60 (41.6 mm O.D.) with a pair of 55 mm ba... ahem.
Won't look much different in the OR renders either way.... can always play with scaling up and down later.
 
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