Hiding your fins in plain sight-- 240 Calories of Fun

[BABAR]

Handy Dandy Rocket Stand doubles as a ring fin.

 

[cwbullet]

What is the fin ring made of?

 

[BABAR]

Ring is cut from a white plastic bottle from pool chemicals.
Paint job on the coke bottle was fun. Sprayed some black paint into the bottle, put cap on, shook it up. Took cap off and let it dry. Repeated twice. Thus all the paint is on the inside. The fins and the inside of the ring were blackened with a marker. The red oN the outside of the ring is Mylar tape.

 

[hornet driver]

Very clever, very clever indeed.

 

[aditat2]

Next you need to do one out of a rum bottle:lol:

 

[Aeronerd]

Brilliant idea. That must really get a ton of attention when yoh launch at a club meet. Did you need to add any weight to the nose end?

 

[BABAR]

Brilliant idea. That must really get a ton of attention when yoh launch at a club meet. Did you need to add any weight to the nose end?

Wow, my own necro thread! 7 years!

Didn’t need any nose weight. I think the combo of the ring and the attaching fin “spokes” provides plenty of surface area. Some guys have done Space 1999 Eagle models (plastic model conversion), I figured a big ring fin on the end with a “lunarscape” decoration around the sides would work. Basically with a big ring fin like this you can make just about anything fly.

 

[jqavins]

Well, I didn't see it 7 years ago, and I think it's brilliant! I've thought many tines about making a rocket out of a 2 or 3 litre soda bottle always been stopped by how to handle the fins.

The 16 oz, 20 oz, and 2 litre bottles all use the same blank, formed by inflation inside a form, so they all have the same neck. The three litre bottles have a larger neck, which I expect should take a BT-50, so D engines could go into the really, really draggy rocket.*

You have proved your brilliance sir, once again.

P.S. I found a good picture and the outer bottle dimension, 5.05". I little bit of the threaded section is visible between the cap and the wide disc (pouring aid) so I scaled that from the overall diameter and got 1.38", 35 mm. The inside should easily be an inch or more. One could likely even get a 29 mm mount tub in there.

P.P.S. This design raises an interesting question that might be applicable to non-novelty rockets. What are the aerodynamics of a ring fin and it's pylons that overlap a tail cone?

 

[CalebJ]

Necro or not, I'm glad to see this. Very cool build!

 

[K'Tesh]

Time for this to be revived again... NICE! That solves some problems I was thinking of for my concept of a bottle rocket.

 

[Grog6]

Cool thing I found by accident about those bottles; if you fill them with boiling water they will return to the original shape.
You can arrest this transformation by sealing the bottle, and cooling the outside.

My GF at the time was making tea in a 2l...

 

[Bat-mite]

Looks like you had a tone of fun with that one! If only I were so creative ...

 

[BABAR]

Cool thing I found by accident about those bottles; if you fill them with boiling water they will return to the original shape.
You can arrest this transformation by sealing the bottle, and cooling the outside.

My GF at the time was making tea in a 2l...

Easy and energy efficient way to make iced tea.

get a pitcher or bottle, doesn’t matter which, my recipe uses two liters or two quarts, difference isn’t significant.

fill bottle with cool or cold water (in other words, I heated) from whate source you prefer (I am fine with tap water.)

for two liters, fill with water, add 4 tea bags, and stick it in the fridge for a couple of hours or overnite (again, doesnt really matter.). I like two bags of constant comment and two of green tea, but any bag will do.

the tea will “steep” just fine in the cold water.

drink as is or sweeten as much as you like. if you do ad sweetener, once you get down how much you will use, it is easier to dissolve it BEFORE you stick it in the fridge, but again doesn’t matter much.

personally, I can’t taste any difference between this and normally brewed iced tea, and it sure saves a lot of energy. Always seemed silly to boil water, steep the tea, then stick a ton of ice in it to cool it off again.

I used to call this “Moon Tea” because it was made in the dark, but the name has been appropriated by the “Game of Thrones” series into something with a somewhat different meaning and purpose.

 

[Scotty Dog]

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Handy Dandy Rocket Stand doubles as a ring fin.

High on Coke.

 

[Pem Tech]

Next you need to do one out of a rum bottle:lol:

Captain Morgan, AWAY!

Just as an aside. One guy who played Captain Morgan in commercials worked for the NRC. Used to take classes at NRC headquarters in TX with people who knew him.

 

[jqavins]

Cool thing I found by accident about those bottles; if you fill them with boiling water they will return to the original shape.

You mean it shrinks back to the size of a test tube?

Easy and energy efficient way to make iced tea... if you do ad sweetener, once you get down how much you will use, it is easier to dissolve it BEFORE you stick it in the fridge, but again doesn’t matter much.

Easier still to boil a little water, or use some hot from the tap, just enough to dissolve the sugar, which is surprisingly little.

I used to call this “Moon Tea” because it was made in the dark...

Sticking the bottle or pitcher out in the sun works, and used to be popularly called sun tea, which I assume you know and took your name from. And therein lies an interesting question: if one makes two otherwise matching batches of sun tea, one in a PET soda bottle and one in a glass pitcher, will there be a tastable difference? The glass blocks most UV, which could very plausibly change the character of what leaches from the leaves, either in the moment that some molecule is or isn't leached or later, when it is or isn't altered while in solution.

What I love about this thread in particular is how it led to other things. My P.P.S. in post #8 (nearly two years ago) led me to create Fire One, a prototype of a ring fin rocket whose ring has the same diameter as its main airframe and is placed at the aft end of a boat tail. (That prototype failed, and in my head I'm still trying to correct the problem.) That in turn led to a project of @lakeroadster's, wherein he took the notion in a different direction. The ideas propagate like biblical begats.

 

[boomtube-mk2]

Let me guess . . . it so-da flies?

 

[Grog6]

Yes, boiling water will turn it back into a preform; flattened a bit by the counter and all but close enough.
She had poured it thru a funnel into the bottle, where she had placed the tbags.
Boiling water went everywhere, as it shrank.
This is pretty simple to test; beware of boiling water, lol.

 

[jqavins]

I'll take your word for it. I'm rather surprised that it would shrink all the way back down, since it's a heck of a long way back. Still, having asked for and received confirmation of such, I am satisfied.