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File 141454081531.jpg - (68.94KB , 240x300 , J528%20Lift%20off%20index%20small.jpg )
6640 No. 6640 ID: 802705
How do you operators feel about sugar rockets?
Expand all images
>> No. 6641 ID: d006d4
Explain. I have never heard of these.

I've heard of mentos, peroxide, plain fucking water, and other odd rockets, but never sugar.
>> No. 6645 ID: 4059f1
>>6641
usually sugar and potassium nitrate.

Very popular with rocket hobbyists and Palestinians.

Performance is rather...meh as far are propellants go, but its chosen for being simple and cheap.
>> No. 6646 ID: 802705
>>6641
I just saw these today. It's as the other poster said, sugar and potassium nitrate. Some pretty cool videos on youtube of what they can do.

>>6645
I imagine there are way better propellants. Seems to be perfect for a beginning enthusiast.
>> No. 6647 ID: fdef19
Slightly off-topic thought:
There would be quite a bit of energy required to break the bond between the potassium and the nitrate ion, and the K/NO3 ratio is 1. So what if one were to use instead an alkalai earth cation instead? They ionise 2+ instead of + and form weaker bonds with anions, so would be far more efficient. Plus fuckyeah red flames if strontium is used.
Though obviously this would be more expensive, defeating the main purpose of using nitrate salts nowadays.
>> No. 6648 ID: c6b4aa
Another mixture I heard of was Potassium perchlorate and sugar. More powerful, but at a higher risk of catastrophic failure.
>>6647
Some times sodium nitrate is used, I haven't heard the result of the experiment. I have some lithium on hand, I should nitrate it to see if there is any noticeable difference.
>> No. 6649 ID: c6b4aa
>>6647
Fuck I totally misread your question. Ba(NO3)2 looks like a good one. Dem green flames.
>> No. 6654 ID: 5b9651
best is potassium nitrate and iron oxide in an epoxy binder.

Google Nakka Rocketry.
>> No. 6696 ID: 2b743f
>>6640
Fuck off James
>> No. 6697 ID: 2b743f
File 141587288128.jpg - (1.64MB , 2560x1920 , jetex.jpg )
6697
Well as we're having a rocketry thread, I'm looking to make DIY jetex motors, I can make rocket candy sure, but that stuff burns way too fast and hot, how could I make a cooler burning fuel to power my balsa planes?

http://en.wikipedia.org/wiki/Jetex
>> No. 6706 ID: 5b9651
>>6697

I looked into this some time back... for reasons.

Anyway the JETEX fuel was a pelletized nitroguanidine and dinitro resorcinol formula IIRC. I dug and dug like a motherfucker, but I could find no sign of anyone ever reproducing it. The chemicals it was made from were originally purchased in bulk as surplus stock from the US space program, and outside of that venue were actually quite rare and expensive.

JETEX was neat, but I don't think you'll be effectively reproducing it today.
>> No. 6707 ID: 5b9651
Correction:
Guanidine NITRATE. Not nitroguanidine.

So it was basically a combination of a fuel/oxidizer compound (guanidine nitrate) with a burn accelerator (dinitroresorcinol).

Resorcinols are highly flammable explosive compounds made by reacting various materials with Styphnic Acid. The common Lead Styphnate used in ammunition primers is also known as Lead Trinitroresorcinol, for example.
>> No. 6746 ID: 7188a3
File 141724904886.gif - (3.24KB , 287x156 , 16774-21-3.gif )
6746
>>6647
Might as well use ceric ammonium nitrate if you want to get into exotic nitrate salts.

>>6697
Consider using concentrated peroxide in some form or other as the oxidizer for cool propulsion. If you'd rather stick to something similar to the original composition, keep urea nitrate in mind since urea is basically guanidine short one amide group. You can get crystals of urea nitrate by simply adding nitric acid to your pee. You're on your own when it comes to the accelerant, though. That shit looks like HE.
>> No. 6747 ID: db7b1c
>sugar rockets
You mean deadly Gaza cruise missiles?
>> No. 6750 ID: 86c753
>>6706

Could I just add bicarb soda to rocket candy to get the desired burn rate, or is there stuff I'm just not thinking of?
>> No. 6760 ID: 7188a3
File 141745375567.png - (3.05KB , 1108x828 , Oxalic_acid.png )
6760
>>6750
No idea. But you should absolutely try it and report back. If nothing else, you'd be able to tell your friends exactly how difficult rocket science actually is.

My wild guess is that adding enough baking soda to significantly slow the reaction would result in inconsistent burn rates. Like so inconsistent the engine is liable to just stop in the middle of the burn. But you'll never unless you try. Also, I'd be inclined to try using oxalic acid instead of baking soda as a moderant. No ionic bonds to break, but the sheer amount of hydrogen bonding should have an overall dampening effect on the reaction with no solid residue. You can buy the stuff in bulk off the internet as it's used to clean stains in wood, among other things.
>> No. 6780 ID: 86c753
>>6760
Rust remover, yeah I know a hardware store that has that.

Thanks
>> No. 6781 ID: 86b7dc
  >>6640
This is some pretty impressive stuff. To think for less than $20 you can make an absolute shitload of entry-level hobbyist rocket engines that can fly in excess of 2,000 feet.

Incredible. It's science like this that gets me hard.
>> No. 6785 ID: cbf3af
>>6781

Its got serious problems though.

The sugar is hygroscopic, so it doesn't store well.

ANY rough handling can cause microfractures in the fuel mass that will cause an explosion under burn conditions (blowout).

If the motors are solid-cast then shrinkage cracks on cooling are a serious problem.

If the motors are pellet-cast, the burn rate can be very unpredictable.

Its neat, but very strictly amateur/palestinian level stuff.
>> No. 6786 ID: cbf3af
I just had a thought.

You MIGHT be able to replicate JETEX performance characteristics by using a fuel of bonded sodium azide (pre-1999 auto airbag gas generator fuel). If you mixed it with sodium bicarbonate as a burn moderator and used a solid binder, like epoxy, it might work.

It might also be a pipe bomb, so I don't recommend trying it.
>> No. 6818 ID: 7188a3
>>6786
I'd expect that to result in a (relatively) mild bang, sending fragments of engine everywhere.

See, azides don't really burn as much as just violently dissociate, which is why they're considered gas generators as opposed to fuels. The very reason they were used in airbags is precisely because they don't generate a lot of heat per mole of gas evolved. Bicarbs slow down combustion by absorbing heat to generate a heavy inert gas; they wouldn't do much to azide decomp rxn rate.
>> No. 6824 ID: 514949
  Why don't you redneck together a hybrid rocket that uses paraffin wax as the solid fuel and liquid oxygen as the oxidizer.
>> No. 6843 ID: 5b9651
  Because LOX is a PITA to make, store, and use.

http://benkrasnow.blogspot.com/2008/08/diy-liquid-nitrogen-generator.html

Small hybrid motors using acrylic and gaseous O2 from a bottle have been done though.

>>6818

Good thinking.
>> No. 6844 ID: db7b1c
>>6843
cant hear anything, why the fuck are they banging pans like baboons in the background?
>> No. 6855 ID: ca62af
>>6824
Because hybrid motors suck, unfortunately.
>> No. 6923 ID: 5f2bf8
>>6750
When I was younger, I was really into developing a smoke grenade mixture for airsoft, and I used sodium bicarbonate to slow the reaction. The smoke mixture is identical to the rocket candy fuel mixture besides the sodium bicarbonate.

All that being said, I was *really* into model rocketry when I was a kid, I built them to use the off-the-shelf Estes engines. You could get bulk engines for an order-of-magnitude cheaper at Toys R Us, but they stopped carrying them, so I kind of fell out of the hobby. I found the rocket candy recipe online not too long ago, and planned to get back into rocketry, but couldn't find a proven design for a nozzle. I have a hunk of Graphite that I planned to make it out of. If anyone is holding onto a nozzle blueprint, it would be most excellent if you could post it. What do you use as an ejection charge for sugar rockets?
>> No. 6929 ID: 06970f
File 142083230389.gif - (4.61KB , 565x294 , k-det4.gif )
6929
>>6923
http://www.nakka-rocketry.net/kappadx.html
>> No. 6930 ID: 06970f
File 142083234020.gif - (7.85KB , 730x365 , nozdwg1.gif )
6930
>>6923
http://www.nakka-rocketry.net/epoch.html
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