/sci/ - Science & Math

Here is the exhaust nozzle.

Are there any chemists than can calculate the potential energy for a mass of fuel? I will have a weight of the fuel mix later.

Forgot my trip!

>lets shoot more junk into space, yay!

>By this time next year /sci/ will be in space. The first prototype motor is complete and almost ready for a live test fire.
>It's a welded steel pipe

Never change /sci/, never change.

fucking amazing thread

>>4156952
>Are there any chemists than can calculate the potential energy for a mass of fuel? I will have a weight of the fuel mix later.
ChemE here, is you mixture massed based of mole based?

>>4156973

Mass. I will have a measurement of what it holds later.

>>4156945
As doubtful as I am of the KNO3 and Sucrose mixture supplying enough energy in the final rocket, I approve of OP.

I will start some number crunching.

>OP's face when it falls back down and comes crashing through a house and killing a baby

In 1.00g you 0.65g of KNO3 and 0.35g of Sucrose
MM)sucroese = 342.296 g/gmol
MM)KNO3 = 101.103 g/gmol

Thus you have:
0.35g of Sucrose / 342.296 g/gmol = 0.00102...gmol Sucrose per gram of rocket fuel.

Sucrose enthalphy of combustion: -5644 kJ gmol-1

0.00102...mol Sucrose x 5644kJ/gmol = 5.771028583...kJ
(2 sig. fig. ) ~5,8 kJ/0.35g of Sucrose

Thus you have 5,8 kJ per gram of rocket fuel of energy supplied by the Sucrose alone.
(simply multiply this value with the amount of gram of rocket fuel measured to find the chemical potential energy inside the combustion chamber in kJ)

[contd. for KNO3 calculation]
(searching the web for enthalphy of combustion of KNO3)

I will have to use a different type of cap if I decide to use a more powerful fuel, it will be too dangerous if some fuel gets crushed in the threads

Sorry, had something urgent to attend to.

Also struggling to find enthalphy of potassium nitrate decomposition...
Fuck it, disregard my previous post.

5 C12H22O11 + 48 KNO3 = 36 CO2 + 24 N2 + 24 K2CO3 + 55 H2O
Enthalpy of reaction: -29064 kilojoules per mole

In 1.00g you 0.65g of KNO3 and 0.35g of Sucrose
MM)sucroese = 342.296 g/gmol
MM)KNO3 = 101.103 g/gmol

0.35g of Sucrose / 342.296 g/gmol = 0.00102...gmol Sucrose per gram of rocket fuel.
0.65 g of KNO3 / 101.103 g/gmol = 0.006429...gmol potassium nitrate per gram of rocket fuel.

Total: 0.007451594 gmol reactants per gram of rocket fuel
Thus you have 29064 kJ/gmol x 0.007451594 gmol = 216.573128...kJ/g

(2 sig. fig. ) ~220+-5 kJ per g of rocket fuel
(simply multiply this value with the amount of gram of rocket fuel measured to find the chemical potential energy inside the combustion chamber in kJ)

[sources: http://www.wolframalpha.com/input/?i=5C12H22O11%2B48KNO3%3D36CO2%2B24N2%2B24K2CO3%2B55H2O]

Physicsfags can take it from here.

Uhh, how will you know if it actually gets into space?

>>4157032
I'm going to invest in a smartphone with some GPS capability and it will get a protective box made to house it. Once it gets to orbit there will at least be a few days to collect data and email it back.

>>4157029
Thanks for the help

>>4156945
Your motor looks kinda off center.

>>4157041
Just how big is your rocket going to be?

Do you know how to factor in air resistance? Taking into account that the composure of the air changes as you ascend.

>>4157044

It's not too bad, I know it's not perfect but this will never be used for flight, just for material testing. The bolt on the end will actually be screwed in so it's pretty centered.

>>4157046

I expect it to be not much taller than a person but possibly quite fat, final dimensions will be determined from the thrust to mass ratio I can achieve. I have an idea for using a buttload of stages to orbit that I would like to investigate.

>>4157041
A cellphone which beams signals to towers on the ground, while it's in orbit... Alright.
And besides- isn't launching junk into space some kind of felony? Managing space junk gets kind of legal last time I checked.

>>4157053

It will be taken into account. It doesn't need any oxygen from the atmosphere and the finished rocket will be a lot more aerodynamic

>>4157062

I'm ready to get the approvals from the appropriate authorities, I'm not going to shoot it into international airspace blindly lol.

>>4157059
>I expect it to be not much taller than a person but possibly quite fat
I hope you've done the research on the legality of what you're doing. I think it's a great idea and I hope you succeed, but I don't want to see you get 20 years in prison for crushing some guy.

>a bolt
>a screw
>-----------
>rocketship

Amazing

>>4156964
lol'd

Why do things have to be going so fast to escape earth's gravity? Couldn't you theoretically drive out at 5mph?

>>4157086
Drive? Shit man you could fucking walk out, it's easy.

>>4156987
>filename
>why dot jaypeg

>>4157086

Because off with your head moron

Empty weight of case, fuse, tissue wad = 102.2 grams +/- 0.1g

Full weight = 107.9g +/- 0.1g

Fuel = 5.7g +/- -0.2g

Video coming soon. It's missing the oomph I expected, will try some different mixes but I think poor nozzle construction on inside is a big problem. A nice taper may encourage it to empty more fluidly.

Looks like some tissue from holding the fuse clogged it though I'm not convinced that's tissue. I poured water over it and didn't inspect.

It is however, fully re-usable.

/sci/ - 1
NASA - 0

>>4157172
when can we expect space flights for our fellow /sci/ residents?

On the one hand, ahaha oh god.
On the other, the pure enthusiasm in the face of adversity is refreshing. Shine on, you crazy fucker. Watch out for the feds.

>>4157174

December 19th + 20th 2012

>>4157206
are you gonna keep this thread going? im tired and need to sleep, but i also want to see the video. if you manage to pull this off, i can only imagine what some underage lurkers will do with this sort of thing.

i, for one, will be launching sex toys into outer space.

>>4157194
I'm convinced that the difficulties of the common man getting to space are over exaggerated to discourage us from trying.

Video available - I can't into editing, this is the best I could spit out (7.5mb) http://www.megaupload.com/?d=V1OER1CW

>>4157242

Downloading

>>4157242

What is this a test of?

>>4157242

What are you trying to accomplish here? It looks like your fuel just burned out without any propulsion.

>>4157242
You've made a tiny pipe bomb. If you sincerely think this is any sort of start on a motor capable of reaching orbit you're delusional. You couldn't calculate the energy content of the mixture never, i really doubt you've calculated just how much it takes to get to orbit.

Bottom line is people with far more knowledge than you have tried, none have succeeded.

I'm entertained, OP. Keep notes on what you try, and at the very least you'll have an interesting story to tell.

>>4157263

Far more knowledge than the collective /sci/?

If they had more knowledge than that, I doubt they failed.

>>4157289

>>Implying 65% of /sci/ isn't pretentious undergrads/high schoolers hidden by a veil of anonymity

>>4156945
There are plenty of books out there. The best way though is to take your base fuel and oxidizer, and get a specific impulse.

>>4157291

>implying the 35% graduates of /sci/ isn't enough to get a phone to orbit the earth.

This is the most amusing troll I have ever seen.
>He thinks some pipe parts will get him into orbit.
>He doesn't know about powdered aluminum and sodium perchlorate...
>MFW

http://projectstratos.nl/
fuck if a couple of undergrad students can get to 15 km

>>4157296

>>75% of that 35% aren't trained highly enough in physics to make this work

ChemE, EE, biologE, and higher math can only get you so far. You do realize that the big boys in aerospace engineering have computers more powerful than every piece of technology in your house combined along with the resources of major universities/NASA/CERN/etc., right?

>>4157315

You do realize that we're talking about a phone right?

>>4157315
>implying the CERN Grid isn't the most powerful computing resource in the world

>>4157079
My thoughts exactly.

>>4157311
orbit is so much harder than altitude, it requires enormous velocity.

High altitude launch platform. 4 helium balloons with a launch platform suspended between.

Tried #2

Same mix (65:35) crushed with a spoon with ~0.1g of powdered Al. Compressed a lot more this time. Total weight with a smaller fuse was 109g (+1.1g fuel). Burn looked a lot more stable with less smoke.

Core for fuse was 4mm diameter ~20mm deep. Next one will try cutting core the full length, will have less fuel but hopefully burns better. Video soon

>>4157242
>>4157172
>>4157125

>Meanwhile at /sci/'s advanced research and development centre "/sci/unkworks"

>>4157090
This is very basic filenaming technology, dude.

>>4157392
That's where the magic happens

>>4157254 What are you trying to accomplish here?

Establish a rough optimisation of basic design aspects before beginning development of larger systems

>>4157053

air resistance can be factored in using F=kv and enough experimentation to determine k. It's not out of line to assume k varies linearly with pressure, which varies more or less linearly with altitude (less actually, but you'll want the spillover as your failsafe)

It's nice that a chemist calculated the energy per unit mass, but you're also going to have to do some hardcore experiments to know force as a function of time. Fnet = ma will do you the rest.

I hope you can solve differential equations... I'm also skeptical you're using an adequate fuel. There will be plenty of information online about how to shape your exhaust to get the most momentum... Good luck!

if the africans can do it...

you should seriously consider primary and secondary thrust, strap it to an undergrad-tier rocket to give it the initial boost (a mile up or so, but plenty of velocity) and rig it to fire the tiny thing off of the the primary rocket when fuel pressure gets low.

Just out of curiosity, how will you know it didn't fuck up at height x >> line of sight.

no more science funding in murrikah this is all what they got left

>mfw this thread

Uploading video with all 3 tests in a row. 47mb

Test 1 - Granulated + shaken mix, lightly pressed, 4mm core 20mm. 5.7g KNO3/Sugar 65:35

Test 2 - Crushed with spoon to fine powder, compressed a lot more than granulated. 4mm core 20mm deep. 6.8g KNO3/Sugar 65:35 + tiny pinch of (0.1g) Al powder

Test 3 - Crushed with spoon to fine powder with almost same mix as Test 2. Remaining fuel = 7.5g 0.6g KClO3 was added to remaining fuel before filling. 1.2g of fuel was unused. Approx 6.8g fuel

Uploading...

>>4157443 Just out of curiosity, how will you know it didn't fuck up at height x >> line of sight.

Just wait and see if there is still a signal after time t. If not then shit.

inb4 OP knocks out the ISS or a spy satellite and causes a major international incident because everyone thinks China did it

>>4157315 You do realize that the big boys in aerospace engineering have computers more powerful than every piece of technology in your house combined

You do realise we got to the moon with practically no computation.

http://www.megaupload.com/?d=4K1NEKCC

3 vids

password is sci

>>4157595

Test #3 was also cored 4mm the full length

>>4157443

He should use strap an accelerometer on it.

>>4157062

>>4157624
>he still thinks humans went to the moon

>>4157723
>>>/x/

>>4157595

Watching the videos I'm going to say the velocity of the fuel leaving is getting faster each time, basing it on the shape of the smoke leaving the nozzle.

I think in #3 the full depth core made more difference than the KClO3. There was a little yellowy shit left which I'm sure was down to this messing with the mixture.

If I can thread the outside of the pipe then I should be able to pour a smelted mix in easily. The smelted mix might be good as the fuel for a hybrid motor that uses either pure oxygen or just compressed air.

>>4157624
It also cost well over a hundred billion dollars.

you should tape an remote controlled iphone or something to it, then you can post from space

Yeah sure, go ahead and kill someone you faggot

OP, where do you live because I want to ride on your spaceship with you. I'll bring the microwave

>>4157733
implying that wasn't for research we don't need to do since they did stop pretending to no what your talking about

oh shit, i think i'll go to the hardware store and build me a spaceship too!

>>4156945
Good luck explaining how you aren't trying to take down a passenger jet to the Man.

>op succeeds
>knocks down satellite by accident
>poker face
>trash floating in orbit gets the credit
>op slightly disappointed
>buys bigger pipe
>a villain was born

So you want to reach orbit with a smokebomb?

bwwwaahahahahahahahahaahhahhahaa

>>4157860

lol'ed. But one mistake
>knocks DOWN satellite by accident

It wouldn't actually be able to knock down a satellite.

>>4157746
It would be helpful if you could grammar and spelling.

And no, most of that was not research. development on the other hand, yes, but OP will still have to develop his equipment (what he is doing here).

>>4156945

OP, I admire your candor.

That said, this will never, ever, ever work. I'm 99% you are a troll, but on the off chance that you are actually someone who is curious about rocket propulsion, I may have some resources that can point you in the right direction.

>>4157891

Why would you think he's a troll? He posted videos and thanked a chemist for doing some calculations for him. He's obviously very sincere.

>>4157891
I think you misunderstand the word troll.

He's just chasing his dream, even if it's unlikely. This has nothing to do with trolling.

>>4157732

What is it that *pops* out of the pipe just after ignition. At 3# it popped out and then rested on the board.

>>4157877
yeah, isn't sugar and saltpeter what you need for that?

>>4157891
>point you in the right direction
>mfw when not propel you in the right direction

My friend and I will be building a rocket with the exact same fuel / oxidizer soon enough. I am sure you can do all the calculations yourself... Here is a chapter from my DIY manual.

>>4157891
moar

>>4157950
Sauce on manual please.

THERES A BIG DIFFERENCE BETWEEN SOLID FUEL ROCKETS AND LIQUID FUEL ROCKETS.

Solid fuel rockets are fucking cheap and easy compared to liquid ones.

>>4157954
I wrote it myself but have hardly gotten started on it. Other obligations in life have kept me from finishing it.

Its just something i did for myself so i could assemble the most useful information from different sources in a reader-friendly format.
If you go to NASA's website you can find an exstensive guide on model rockets and calculations.

http://microgravity.grc.nasa.gov/education/rocket/rktengine.html
http://microgravity.grc.nasa.gov/education/rocket/rktengperf.html

>>4157968
Thanks.

/b/ is already in space...

>>4157972
That poor toad.....funny though.

Why don't you buy a large weather balloon, make a light, horizontal platform beneath it, put your device on one side of the platform and a counterweight on the other side consisting of a small video camera pointing up. Put a timer on the rocket to go when the balloon has reached maximum altitude. The video camera will record the launch to at least see if it's going up.

The balloon will take you the first 20 kilometers, which are the hardest. The next 80 kilometers are up to your rocket.

>>4158032

>http://www.youtube.com/watch?v=WfJNNXTt85Q

Dream on op

I asume you're American, Rocket Scientist? If so you might want to consider a desert as a launching base if you have the means to get there.
I would also keep the object as small as possible. I'm not aware of the security in your country (American or not) but I assume most countries have radar that will pick up large objects and raise questions. I don't believe you will have any luck taking the 'legal' path so I would take the necessary precautions to remain anonymous.

Good luck and I look forward to hearing more. This thread is interesting even if it will never be more than a thought excercise.

>>4158077
Are you fucking kidding me? Well, so much for my idea being new. I might try it myself someday.

Say you wanted to launch a rocket from a cluster of weather balloons at 20 km. You need to get to 100 km to be in space. Roughly what size rocket do people use in competitions to get this high? How much do they weigh?

If things go well, post the video on YouTube. If things go badly, post the video on Funny or Die. If things go very badly, post the video on LiveLeak.

Did some calculating to get an idea of the mass flow. Measured roughly the time it took for the fuel to ignite properly until the last puff of smoke.

Times were taken from the sequenced video. Due to the short unsteady burn it's hard to say the peak velocity because they all linger a little bit. Larger motor that burns longer will be better for guessing peak flow.

Highest avg is up to 0.5g/s

>>4158503
and if it goes VERY badly, someone will post if for you on liveleak.

>>4158509

>mass flow = weight/time
> MASS flow = WEIGHT

nice try.

>>4158509
You might try mounting your engine on a pendulum, to get a better sense for the thrust you're developing.

>>4158526
>implying metric doesn't

>>4158652

you're damn right I'm implying metric doesnt!

>>4157918 What is it that *pops* out of the pipe just after ignition. At 3# it popped out and then rested on the board.

Wad of tissue that holds the fuse and blocks stray sparks.

OP... set yourself a more modest goal. Say... a successful launch. Forget about orbit, forget about space for now. You'll be taken a lot more seriously.

Also, I've made a handful of sugar rockets myself (over HALF of which have been successful!), and I highly suggest you check out James Yawn's website, and Richard Nakka's if you're interested in some of the more advanced principles and theories and methods.

>>4158526
Better?

>>4158707
you gotsta be trollin'

>>4156945
>KNO3 / Sucrose
we called that mixture "candy propellant" back in the day

>>4158704 Forget about orbit, forget about space for now. You'll be taken a lot more seriously.

What's the point in doing it at all if you're not going to do it right? Orbit will be easy, it just takes a lot of fuel, careful planning and a simple thrust vectoring system.

It's more realistic than LFTR

>>4158717 candy propellant

Note hybrid with oxygen for future.

>>4157732

>>4158737

Yes, this. Very easily done.

I'm curious to see what will happen with a full KClO3 / Sucrose charge, wall thickness seems sturdy enough.

OP, you remind me of that kid that built a nuclear reactor in his backyard.

>>4156945
No De Laval nozzle? You should add a de laval nozzle

>>4158886
>>seems sturdy enough
Those are the famous last words of many would be rocket scientists, please do some calculations first to make sure you haven't made a pipe bomb.

Good luck spacebro!

>>4159200
i remember that. so fucking cool

>>4159332
Just finished watching the video.

http://www.youtube.com/watch?v=1Yk8dmw-hkI
http://www.youtube.com/watch?v=jj8E5wXQJxg

>>4159345
>he lives in the same state is me, god damned backwards piece of shit Michigan

Why am I not surprised

anyone know what he's doing now? is he just making money off interviews?

Hey OP, while space technically starts at something like 65km, obtaining orbit, is much harder.

I've made a few potassium nitrate rockets, and they're quite fun. You're using steel. This will fail. Either compressed paper, or aluminium is great. Aluminium is probably better, but I've never used it, only PVC (it melts with too much fuel).

A thing I have to ask is, are you using powdered fuel or baked? I believe baked fuel will give a much better fire rate (although tetchy).

I watched the videos, and the velocity that thing could create is veeeerry small. My rockets create a very large amount of force, and I've made my rocket go out of sight upwards. The rockets were approx 9.5mm long, with 20mm kitty litter (bentonite clay) plugs on both sides. I can't remember the nozzle size, but it may have been 5mm. The rocket had no fins, and used a bamboo stick (about 600mm long) to keep the rocket straight.

I used a sparkler for ignition. The fuel was 3:2 KNO3/Sugar by volume. Apparently the purity of the KNO3 was 26%?

I guesstimated that the rocket went 1-2km, maybe more, because you couldn't even see the smoke trail.

This was the result of 8 previous test flights.

Unfortunately, I should have used a GPS tracker, but they cast about 40 dollars a pop.

Oh yeah, I did not gain any permission from authorities.

Congrats OP, you made a pipe bomb, enjoy your hospital

if you put enough energy per mass into the rocket, it might break the 100Km barriar, but it's not going into space unless it gets enough tangential velocity.

just bumpin
http://www.youtube.com/watch?v=nyUE4Bsjytk

How about some sort of airlaunch? Get some weather balloons and try and get to ~100,000feet and launch somehow from there. You're closer, plus less atmosphere to slow you down, I reckon you could get close if everything worked properly

>>4158134 I asume you're American,

Nope.

>>4159224 No De Laval nozzle? You should add a de laval nozzle

De laval nozzle is more difficult to fabricate and as you increase the strength you want the difficulty shoots up. Need some form of rolling machine.

Though I'm sure the nozzle I'm using now is getting in the way. On the inside it's an abrupt hole on the end of a piece of bar. Very far from ideal.

Currently trying to figure out a way to estimate the exhaust velocity and internal pressure. The choke in evacuating the gases means a high % of the energy put into each particle will be wasted as excess pressure and heat.

Maybe an ideal solution can be modeled and do an efficiency approximation from it.
>>4159964 Launching from balloons

Adding a balloon makes for an additional system to worry about. How can you be sure the rocket is at the right angle and not literally aiming for the ground with a full tank of fuel?

Also on the weather balloons, the expense of rigging up a launch system on a balloon is greater than just adding more fuel to the thing you're already developing.

>>4160550

Also hydrogen is probably more affordable to make than helium but it's dangerous.

Showing off one of the difficulties in trying to shape a de laval nozzle. Hammering and cold working.

One way to do it is to shape two cones and join them in the center. Trying to work a pipe down to such a small diameter results in cracking and cracking can lead to explosions.

Other methods suggested are pinching a pipe. Best way I can think of doing this is with shaped high pressure rollers. This also draws the material a lot resulting in thinned walls and work hardening.

Best way is to machine it from a solid lump but this is costly and requires a quality machine.

It can possibly be accomplished with thin sheet metal to get the correct shape with a heatsink insulation to improve strength.

>>4161008

In above picture I reduced internal diameter from 12mm to 10mm.

Found a socket that looked ok to try as a nozzle, it has a 6mm square with a 4mm through hole. Weld the slightly reduced pipe to the socket.

This should be a much better performer than Prototype #1. I shall do a sketch of the internal nozzle problem.

The corners of that square are going to get silly hot compared to a circle.

Bonus points to anyone who can explain why.

The slight reduction has allowed to a better weld area. Welding should repair most of the crack that was in it but this will not be acceptable in the high power system.

Lumps are welded so it still fits in testing hole

what are you going to launch it with? whats going to keep it going

This is maybe the size I'm aiming for one of the main boosters. Filled with smelted mix, full core (can design core shape for planning the burn) and possibly with oxygen inlet at the top.

It's looking possible to actually mould the stages directly onto each other in a stepped fashion, lighting the next stage and jettisoning themselves in one go. Having so many stages may be unheard of and not good for popular areas but the more active weight loss is convincing for helping efficiency.

>>4161064
I know sharp radii are stress concetrators but I don't know if this applies to thermodynamics as well.

>>4158707

The numbers are speaking for themselves. In one day the mass flow was doubled just by tweaking the shape of the core and there's still a pile of other things to improve.

If I can find a way to measure thrust accurately I can set up a sensor and datalogger and chart a timeline of how it is burning. When I get the accurate timelines I can begin working on the tracjectories and arrangement of all the boosters.

OP, do you think it is possible that i could learn all of this stuff on my own time or would i have to go to school? i've always been interested in physics but im not sure if i can do it

>>4161126
I replied to the wrong post here >>4161119
I wanted to reply to >>4161034.

Is it because of sharp radius and similar mechanism to stress concentrators or because of the extra pressure from the two expanding perpendicular surfaces?

This is essentially what the first case and nozzle are like.

>>4161126
OP can you answer to me here? >>4161159

>>4161159

Keep thinking :) There's still more

>>4161208
If you also mean that the circle has a larger surface area which will dissipate heat faster and more evenly yeah that's pretty self-evident but I really can't think more now, I'm getting really sleepy and I don't know nearly enough about thermodynamics to find out on my own.

Just spill the beans mang I need to know before I sleep

>>4161208
puuhlease OP I must know

>>4161208
OP please don't let me down

>>4161208
I'm starting to think you don't know why and just threw it out there for gullible people

>>4161369

It's interesting to think about, everything you've said contributes. The gas gets funneled into the corners with a higher pressure is another thing.

>>4161391
>The gas gets funneled into the corners with a higher pressure is another thing.
Hm didn't think about that. I thought of the secondary effects because my knowledge of thermodynamics and fluid mechanics is not that extensive. Anwyay, did you study anything related to this?

Test firing nozzle 2. Videos soon.

Case + fuse = 98g
Saving of 4.2g

Holds ~8.1g of fuel.(+1.3g)

First try was with 5mm nozzle hole + 3mm core, wasn't great. Got clogged and took too long.

Second try will be with 7mm hole + 5mm core

>>4159451
I'm not talking about model rockets, this thing has to get out of the atmosphere consistently. Other materials will be considered for other bits but steel is the cheapest and strongest for now.

>>4157029

So I tried some calculations with these numbers to approximate how much of the energy the mass takes on per second and used this to estimate the power output.

I've slipped up somewhere.

Think I've caught a disease because of christmas shopping. Sick people more likely to be going into an already a more heavily densely populated public area. Early rest for now. I'll make a rar with the solidworks files and spreadsheet

>>4162307
>1.2MW
>7g fuel

Needs more cowbell

>>4156945

1 year from now:
>full scale rocket ready for launch
>/sci/ prepares for momentous occasion
>rocket malfunctions at apogee
>/sci/ gasps in horror as missile careens off course into iran/india/china/russia
>suddenly this project becomes very /k/ related.

>>4162307
>I've slipped up somewhere.
Yes, in thinking that you have the expertise to engineer this thing from the ground up.

Do yourself a favor, swallow your pride and go follow someone else's work until you can reproduce a working rocket engine. Once you've gotten to that point, THEN you can start thinking about designing your own shit.

http://www.jamesyawn.net/modelrocket/index.html

http://www.nakka-rocketry.net/

Now, while I'm quite certain you won't be achieving orbit, I DO want you to at least achieve some level of success, and I AM more than happy to help you, but you HAVE to believe me when I tell you that you are getting WAY ahead of yourself right now. A few initial flaws I see with your design already:
>Extremely poor nozzle design (WAAAAY overexpanded and WILL suffer from detached flow)
>Casing is extrmely heavy (not a fatal flaw by any measure if your only intent is static tests)
>Compacted powder propellant is unpredictable and has mechanical properties that are unacceptable for larger motors
>You're looking at ENERGY instead of IMPULSE for a ROCKET MOTOR (I mean, seriously, dude. SERIOUSLY.)
You really ought to back up to square-one at this point; you haven't lost too much yet to get off on the right foot. Plenty of others have blazed this trail before, and fiddling around for weeks/months trying to rediscover these simple fundamentals is only a waste of your time.

>>4164877
Totally possible; see:
>Gunshots
>Firecrackers
>Other small explosions

>>4164979

But I have to understand how much energy there should be available in perfect conditions for accelerating the mass in order to know realistically efficient it is.

I'm not ignoring those equations but without a figure for pressure or velocity they're not relevant yet.

Has anyone got rocketry resources they want to spam, this would be the thread to do it.

>>4165070
>But I have to understand how much energy there should be available in perfect conditions for accelerating the mass in order to know realistically efficient it is.
Newsflash: Rocketry is inherently inefficient. Efficiency is nothing but a curiosity in this arena. What you SHOULD be looking for (and is in fact ALREADY AVAILABLE for a proper KN/SU formula) is SPECIFIC IMPULSE, which is MUUUUCH more directly relevant to your rocket's performance.

But again, if you don't know that already yet, you REALLY need to be trying to follow someone else's lead instead of crippling yourself with a motor who's performance will rival nothing but perhaps 14th-century bamboo rockets.

Look at James Yawn's how-to. Follow it faithfully; DO NOT diverge from his instructions until you've successfully launched a motor. THEN you can start thinking about designing your own motor to achieve higher-performance or reusability.

Did OP just make a pipe bomb?

>>4165086
>implying I haven't heard of impulse

I'll be getting to it.I know rockets are inefficient but being able to know the efficiency will let me know how much energy is being lost within the rest of the vessel. Important for designing the structure of more crazy powered engines.

>>4165120 Did OP make a pipebomb?

it has the power of a wet fart

>>4157972

lol'd

/sci/ can beat that with less animal cruelty

>>4161008
The convergent section of a De Laval nozzle isn't that critical. With enough internal pressure, you could probably get away with the converging "cone" being completely flat without much loss in efficiency. Focus on the throat and the divergent section.

>Take a ~1cm long piece of soft steel stock (softer = easier to work)
>Drill hole through the middle to form your throat
>Grind a gentle diverging cone with a dremel or something, no more than ~3x the throat diameter
>Weld that bitch in there
>???
>Proper De-Leval nozzle!

>>4165121
It isn't important. You're wasting your time.

Liquid hydrogen rocket engines, which are considered the best-performing chemical rockets in existence, are actually some of the LEAST efficient, simply because they're injecting so much velocity (and energy) into their exhaust jet. But they're used anyways... why? Because hydrogen offers more SPECIFIC IMPULSE, meaning that - while you are "wasting" more energy per launch than something with a larger mass fraction (technically more efficient), you are still achieving better fuel economy because hydrogen offers more energy and impulse per pound.

Fun fact: In the domain of rocketry, the humble water rocket is unrivaled in terms of energy efficiency.

Second nozzle test fire videos are up. I've included my spreadsheet data and 3d files.

http://www.megaupload.com/?d=5WADH9G4

Larger modular hybrid motor.

Will be cast KNO3 mix with a compressed air inlet at the top. Al powder may be added to increase burn temperature and momentum per unit fuel

>>4165319

It's designed to built and fueled in separate pieces for convenience.

This shape also allows us to plug a complete engine onto the bottom of next stage during the casting without complicated release mechanisms. This will open the possibility to large rockets made in many small bits benefiting from the constant shedding of excess material.

>>4165189

Not so. Ideal exhaust velocity depends on mission dV. As I recall, the ideal exhaust velocity for an ideal rocket with fixed exhaust velocity, in terms of energy, is actually equal to mission dV.

>>4165486
Are you a magnet?

Videos are in the process of being uploaded to the official /sci/-unkworks youtube channel

Tested some full chlorate mixes and tbh they're looking like the only realistic booster that isn't hybrid.

First chlorate test used both nozzles. Fuel mix of 7.2:3.5 KClO3:Icing sugar.

Second chlorate test used 6.5:3.5:0.3 KClO3:Icing sugar:Al powder (spherical)

Second test the casing was noticeably hotter than first, this was to be expected because of adding Al. First test could have been handled by bare hand without much cooling time.

All videos will be available shortly
http://www.youtube.com/watch?v=UobH4XL4jls

Dual test - http://www.youtube.com/watch?v=qitNsfwm-Xs

Chlorate + Al http://www.youtube.com/watch?v=PD7pbVmgnzY

A reactor for chlorate production will be on its way

Please tell me OP has some decent education that is related to space flight.

Anyone got ideas for measuring force accurately?

Was thinking a piece of flexible steel overhanging something and taking a measurement of how much it bends but I would need good values on the properties of the steel.

>>4165926
I have the internet and my own brain

>>4165946
Put the rocket head-down on a kitchen scale.
Reset zero-point to the weight of the rocket.
Ignite.
Check read-out several times per burn.

Just tried it with the scales but it didn't register anything so they must be broken or something.


http://www.youtube.com/watch?v=6EBmIlpTHQQ

>>4166172
Let me guess: the diagonal something that intersects with the rocket is the brace holding the rocket?

That defeats the whole exercise. The point was for the scale to take the whole weight of the rocket.

Just cut a piece of the 2/4 with a hole in it so it holds the rocket tightly. Put the piece on the scale. Attach the piece on the scale platform with cableties or something.

Make a note on how much the whole contraption weighs.

Ignite, make a note on how much the contraption pushes the scale down.

Detract the first figure from the second and you're there. If you also time it, you can calculate the specific impulse.

The rocket was loose and free to move in that brace.

Maybe the thrust twisted it in the hole, locking it instead of letting it push perpendicular to the scale

isn't Earth's escape velocity somewhere around 11,000 mph?

how the hell are you gonna achieve that?

I need 17,500mph to land me in a similar orbit to the ISS

With rocket power it's achievable.

I'm starting work on a method to produce KClO3 in bulk, cheaply. Electrolyse some NaCl -> to get NaClO3 -> Add KCl and precipitate KClO3. Once there is enough of this built up I can begin on a series of 'fuel cakes'.

Each cake will be approximately 100g with its desired core shaped in the center. These cakes will be stacked and stuck inside the combustion chamber. This will grant me highly consistent burn patterns and a lot of control over the entire core profile.

It will be almost trivial to get the desired velocity with this fuel. I expect a month will be wasted figuring out the optimum configuration and placement of motors.

>>4166283
11.2 km/s

But you don't have to go that fast with rockets. Escape velocity means that you would need to have a STARTING velocity of 11.2km/s so you could escape the Earth's pull by inertia alone.

If you could get a powersource and a propellant compact enough, you could go at the speed of a regular car and leave earth.

>>4165926
It's very clear that is not the case.
>>4166417
>Playing with chlorates
OP, for your own sake, just stop. I was hoping your ignorance would prevent you from actually producing anything potentially harmful, but it is becoming exceedingly clear that you have every intention of blowing yourself up.

Stop. Now.

OP, realize that the smallest, simplest rocket that has achieved orbit was Japan's Lambda 4, and it needed four stages, was 16.5 meters tall and 0.75 meters in diameter. The smallest proposed orbiter is Indonesia's RPS-420, and it will be 9.5 meters tall, have three 0.42 meter parallel stages, and isn't being built because Indonesia (a whole country) can't afford to.

Orbital rocketry is not a backyard endeavor.

I believe in you OP

Why the fuck is this still going? I thought he was a troll, but I guess he's just a guy the difference between mass and weight and thinks kg is a weight

>>4166417
>Calls self rocket scientist
>calling grains 'cakes'
>using chlorates
lol

>>4167990 Japanese Lambda + Indonesian RPS-420

I've never heard of those before, thanks. Indonesia barely counts as a country so they don't count. The Japanese one DID work with a success rate of 82%, I know I'm not perfect and am expecting some failures so 82% is my minimum acceptable rate.

16m x 0.75m is a bit OTT.

http://sugarshot.org/project_description.html

These guys are using sugar mix alone and their rocket is barely that size.

>>4168149 Chlorates lol

It's what they use in all of the professional motors although they have access to Ammonium Perchlorate which is probably better but I've never seen it available.

>>4167990
Back to the weather balloon idea:

Say you manage to get 20 kilometers with balloons. You're already past the hardest part then. Aren't amateurs getting up about 80 km from the ground now? I didn't perform any calculations, but maybe a rocket that could rise 0-60 km could also go from 20-100 km, the increase in height do to the lack of any air resistance. How big are the amateur rockets that go up to 60 km? More importantly, how much do they weigh?

Godspeed

>>4168601

This guy made one a Saturn V model at 36ft tall with 1400lbs of fuel and only reached 4440ft which is pretty poor tbh. That was made from wood and fibreglass.
http://www.popularmechanics.com/science/space/rockets/4315103

>>4168619

Well, from this:

http://www.rocketryplanet.com/content/view/12/28/#axzz1h8frIW3m

They made it to 85 kilometers with a 13 foot long rocket, total weight about 540 lbs. If you want to get to 60 kilometers, you should be able to do it with a 400 lb rocket. Balloons could carry that up to 20-25 km. I don't know what diameter hydrogen balloon you'd need though.

>>4167686 OP, for your own sake, just stop. I was hoping your ignorance would prevent you from actually producing anything potentially harmful, but it is becoming exceedingly clear that you have every intention of blowing yourself up.

I appreciate your concern but I'm not interested in blowing myself up. Health and safety is driving my design which is why I'm imposing a weight limit per cake and avoiding liquid oxygen motors.

>>4168697

I think once you start talking about the weights of these rockets hydrogen/helium balloons get prohibitively expensive. You need a big ass balloon for something this size.

One thing these guys keep repeating is the focus on a single stage. No one has got to orbit with a single stage.

http://www.ddeville.com/derek/CSXT.htm

72 mile altitude, 21ft tall, 724lb lift off weight, 435lb fuel, Mach 5

>>4168560
>It's what they use in all of the professional motors
NO
IT
IS
NOT

OP, stop before you hurt yourself, really. Chlorates are unstable and were the cause of many violent amateur-rocketry accidents back in the 1960s (the so-called "basement bombers" which haunted the field of amateur rocketry for decades).

YOU NEED TO STOP, OP. WHAT YOU ARE DOING IS DANGEROUS, AND YOU HAVE NOT DONE ENOUGH RESEARCH YET.

>>4168762
Well, fortunately a 5 cubic foot tank of hydrogen at 5000 psi can lift over 120 lbs. Four tanks can supply you with enough volume to lift the rocket, and I'd assume you'd need a few more tanks to take you to higher elevations.

I cannot for the life of me find ANY information regarding how much a tank of compressed hydrogen costs. I searched online for a very long time. NOTHING. Can anyone help? Like a large tank about 4-5 feet tall.

>>4168940
>Well, fortunately a 5 cubic foot tank of hydrogen at 5000 psi can lift over 120 lbs.
That's not how pressure vessel capacities are measured, bro. "Cubic-foot" ratings are representative of the cubic footage of UNCOMPRESSED air that you can squeeze into them. Thus a "120 cubic foot" tank would only lift about five pounds.

>>4168940
Sorry, I think I finally found it. At $100 per kilogram, using the ideal gas law you get about 25000 liters of hydrogen at 1 atm. You can lift one pound with 407 liters therefore $100 gets you 61 pounds of lift.

To lift the rocket and stage, it'd cost you about $800 for the hydrogen.

>>4168949
I'm talking about a tank that is compressed. If you had a volume of 5 cubic feet, and inside that volume you had compressed hydrogen at 5000 psi, then you would get that much lift from that tank. Sorry if that was unclear.

>>4168940
Sorry, I think I finally found it. With 1 kilogram of hydrogen, you get about 25000 liters of hydrogen at 1 atm with the idea gas law. Hydrogen is about $100 per kilogram. You can also lift one pound with 407 liters of hydrogen. Therefore, $100 gets you 61 pounds of lift.

To lift the rocket and stage, it'd cost you about $800 for the hydrogen.

>>4168980

+ you need to factor in the very large balloon. I'm thinking of the massive balloons required for experiments that were around the 1ton mark in the 1970's. They had problems with the material being cigarette paper thin and prone to badly tearing. I'm not sure how they've progressed in this field but the size of the balloons won't have changed.

I think if I were to be handling that much hydrogen it would be more economical to pump it into a combustion chamber and make a motor with it. Would need to fabricate a special tank to suit a rocket, while possible it's an expensive pain in the neck if you find that it leaks at all.

NASA put people into space with less computing power than your average phone. We can send a phone into space with the computing power of a few people.

Hell my university even has a space team that's gonna send a satellite into space in the next couple years, granted it's with the assistance of actual space organizations.

>>4168897 Chlorates are unstable and were the cause of many violent amateur-rocketry accidents back in the 1960s

They're noobs from the 60s that didn't know what they're doing. Keep everything super clean, absolutely no prolonged storage and leave your general dumbfuckedness at the door.

Dangerous chemicals only become dangerous when handled and managed incorrectly.

>>4169102
Yes, I was calculating that in the mean time. I don't know if hydrogen balloons are necessarily different from helium balloons, but weather balloons to hold the capacity I need would run a few hundred dollars total.

If we're talking a very special kind, then I have no idea what the cost would be. I'd need to make sure I account for the expansion of the gas at higher altitude.

>>4168970
Well in that sense... there ARE no available 5000 PSI pressure vessels with 5 cubic feet of internal volume.
>>4169132
You've provided zero indication that you are any better than they were. I don't really like to insult, but you have displayed an astounding level of ignorance in this thread, and I sincerely fear that you will hurt yourself if you screw around with chlorates.

This is the last time I'm going to warn you. Don't make me say "I told you so."

How about:
Hydrogen balloon for a first stage, then the hydrogen in the balloon is redirected and burnt as the second stage.

I keep reading about rockets reaching 20-100km. Sputnik 1 orbited in the area of a few hundred km above sea level, iirc. A geosynchronous orbit is something like tens of thousands of km.

>>4169210
I know it's stored commonly at 5000 psi. Didn't know a volume though.

It doesn't matter anyway. It's commonly sold as 0.6 kg cylinders. I can do a cost analysis based on that pretty easily.

>>4169305
One difficulty I can see is that you would need to get it somewhat compressed, otherwise it will be too diffuse to provide enough propulsion. If you need to compress and redirect it.

>>4169421
They're available in size 'W' cylinders. Stats on my Argon bottle says its filled between 215-230 bar at 15ºC, 11m³. I'm not sure what the hydrogen is filled at.

I've no experience with compressing gases or gas pumps. Can a regular air compressor be fitted with a line to supply bottle, purged and manually cranked over to pressurise any gas?

I certainly won't be considering doing this with H2 unless I have an entirely inert room to work in which I won't.

>>4169710
It says the gross weight of the cylinder is 86kg, makes no mention of the weight/mass of the gas.

Is this the same guy who wanted to blow himself up with his dad?

>>4169722

What?

>>4169210 I sincerely fear that you will hurt yourself if you screw around with chlorates.

The work I am doing is not "screwing around". There will be a full risk assessment at each stage and precautions will be taken as necessary. If viable, the chlorates will be converted to the more stable form of perchlorates, this does not imply it will treated as if it were safer because it will be just as combustible as before.

Thanks for your concern.

>>4169305
>Hydrogen balloon for a first stage, then the hydrogen in the balloon is redirected and burnt as the second stage.

>>4169722

lol?

The bleach is on the boil

>>4170148
GL neither believes nor disbelieves in bleach

>>4170148
I need scientific evidence that that is bleach or I won't believe you.
>you expect me to take your word for it? On good faith?
HA

FUCKING HOW DO 4CHAN

FUCKING BLEACH

shit i want some potato chips

>>4170179
It might sound look and taste like a good idea but maybe it's not.

OP, please be careful. You're playing with dangerous chemicals, and as others said, coming very close to making a pipebomb.

So in a few hours hopefully this will have boiled down to about 400/500ml at which point I will let cool and there should be some NaCl precipitate that will need filtered out. Once filtered I'll add some KCl (48% NaCl fuck), bring it back to the boil for a few minutes, let it cool, put it in the freezer and hopefully I will have some more KClO3 ready to be filtered.

My fagtag won't stay on

mfw white people on sci are less able than a bunch of ragtag congolese

http://www.liveleak.com/view?i=591_1249254184

>>4170297

How the fuck did it go like that? lawl

>>4170321

because they didn't have the brilliance to use a welded piece of steel instead

Two hours... This shit is slow.

Can anyone see any problems with adding a KCl/NaCl combination rather than pure KCl? I'm going to be extracting NaCl then adding it again by the looks of it. Hopefully the saturation won't be too much to overwhelm the KClO3 as it comes out..

>>4170297
Zero to FFFFFFFFU- in 0.1 seconds

>that's rocketry

Mine shouldn't be as randomly disastrous.

Some of these made my butt clench
http://www.youtube.com/watch?v=13qeX98tAS8

<-- Picture related, he has the right attitude

I think I reduced it too far because it's gloopy as shit without even adding the KCl.

1.4L -> 0.5L

It did burn a little on its own so that's a little promising.

>>4169722
Well, there was a guy on last week who wanted to make his own hydrogen using iron and concentrated hydrochloric acid. He did all the calculations (surprisingly well) and said he'd have something like 500 lbs of ferric chloride that he'd just put in a river.

>>4170693

Sounds like a bro

so you're not going multiphase rocket, a la tsiolkovsky?

>>4170693

All fear the survivors.

>>4171069
>Plan B

>>4170693
That was the guy

BAMP

this thread

Added the KCl (51%) / NaCl (48%) this morning.

Brought it to the boil and then let it sit to cool down. Foolishly I added a little more salt while it was cooling which I'm almost sure didn't react at all.

Filtered it while it was still warm to try and catch what little bits of KClO3 precipitated out first and to leave what saturated NaCl in the bowl. Once it's cooled I will put it in the freezer and see what happens.

Some de-ionised water was added to the mix to thin the mixture a little and to give the NaCl more room to get stuck in.

Video of brewing / salt addition will be up soon.

Pic related. Slightly warmed with first salt added

A small stir and more heat you can see it reacting in quite nicely.

Top from left to right
What filtered out from the warm mix
What was left in bowl after filtering. Excess KCl/NaCl is there in a puddle + bits of other unknowns

Bottom from left to right
First crap that was filtered and left in the original bowl. Suspected NaCl with maybe some NaOCl
Remainder of filtered warm liquid. KClO3 should appear in this!

>>4173725
oh my good god are you boiling bleach for chlorate? Man, either buy it or make it electrolytically.

My vid http://www.youtube.com/watch?v=4XlRsEOZITg

I'm confident I've boned myself royally with the KCl/NaCl crap. Though I'm sure with some extra steps for refinement it can be taken out.

I DID try to find some zero sodium salt but no luck so far. I went to a "health store" to ask them if they had some and while I was waiting to be served I got to experience my first real life encounter with homeopathists.
They (shopkeep/customer) were blabbing on about something but key points in their conversation included how homeopathy is a placebo and you have to think positive for it to work or it won't. Kids don't understand what a placebo is so it doesn't matter if they believe in the medicine so long as they believe in the parent. The "medicine" will take about 4 weeks to work and she should come back after that time to discuss it again.

I quietly facepalmed while browsing their overpriced garlic pills.

>>4157206
Well perhaps it would be better to not fixate on a certain date but rather chose a day based on appropriate whether for launch.

>>4173748
weather*

>>4173742

I don't have any graphite for the anodes or a prepared power supply. Does it have to be graphite? I have some tungstens, bits of stainless steel and regular steel, 2mm aluminium rods and copper wires.

Info on preparing a power supply and the solution you used are much appreciated

>>4173743
Homeopathists who know they sell placebo? wow.

Your KCl... try an industrial hydroponics store or try the water treatment chem companies. Especially america... water softeners, that kind of shit. A good hydrponics supplier will hook your up, lol. Nitrate, S, acids, and when you get known there you can start buying vermiculite for shrooms and grow lights for your weed...

I like what you're planning... I only ever got as far as explosives and bottle rockets, lol. But I think your rocket will need to be very big to get up into space. This is going to cost some serious $$. Solid propellants will work but you're going to need something more high performance than a chlorate or perchlorate/fuel mix.

A real boss would make it detonate an explosives payload at it's apex, hahaha.

>>4173751

Well I'm not going to spoon feed you... valuable skills are developed when you find stuff out yourself. That video has a lot of information on it, and a few google searches will reveal how to make your PSU suitable for the task.

Check sciencemadness and do google searches for chlorate cells. If you are in america, I suggest you just buy it. Im in hinky dinky NZ so its impossible to get it here and one must synth it.

The source of the anodes is described in the vid too.

>>4173761
Yes yes the source is in the video says gouging rods but I don't want to go to my welding supplier just for these. I'll be paying him a visit soon anyway but in the mean time do you know off-hand are there other suitable materials?

I'm not asking to be spoon fed, it's just in the interest of saving time. If there was a particularly helpful tutorial you followed it would be kind of you to share.

I can no longer directly buy the chlorates I want and for the supply required I have yet to determine whether the boiling or electrolytic method will scale easier and more efficiently.

Is there any problem with connecting multiple power supplies to the one bath?

So there's definitely something here. It's been sitting in an ice bath for just over an hour and you can see a bunch of particles suspended in it. Will filter and lay it out for drying tonight. The fluid has kept it's thick bleachy properties however this doesn't appear to be a problem except filtering is slow.

I'll be going shopping tomorrow at the electronics store to pick up a bunch of crocodile clips at the very least. My knowledge of electronics is poor, can anyone think of stuff that will be useful that I should pick up while I'm there?

At this rate I hope to be testing a 1kg motor next week!

>there is no spoon

Also, I need ideas for getting estimates of the chamber pressure.

Once I get an idea of pressures involved I can finally make a start on doing some calculations for selecting the appropriate materials and wall thicknesses for the body instead of being way OTT.

http://www.nakka-rocketry.net/kdx002f.html
>To measure chamber pressure, the motor bulkhead was tapped with a pressure fitting which was connected to a 4" 0-2000 psi gauge. To prevent damage to the gauge by hot combustion gases, the connecting line was filled with oil (SAE 30).

Well shit this isn't a bad idea. The hydraulic load cell couldn't be simpler and connecting the pressure gauge with a hose filled with oil is genius.

His motor hits a max pressure of 1200psi so I'm going to say tripling that figure won't be a bad start to design around.

3600psi = ~25MPa

For a 60mm mild steel cylinder with a yield strength of 400MPa the wall thickness should be approx 1.875mm

2 wall thickness = pressure * diameter / yield stress

>>4173717
you sure were really excited...

Approx density of pressed KClO3/Icing sugar fuel =

Weight / Vol
8.5g / pi*(0.6cm²) * 6cm

1.2525 g/cm³

For 1m steel tube with an I.D of 60mm and wall thickness of 1.875mm

Mass = 2879.34 grams

Volume = 2827.433 cubic centimeters

Total fuel mass (ignoring core) = ~3541.36 grams

Assuming 10mm dia core = ~2513.3 grams fuel

Total mass = 6420.7 grams (Using no core but assuming this to cover nozzle and bits)

I think about 30 steel chlorate tubes for main engines with just as many KNO3 cardboard tubes will suffice to reach space.

Having so many separate engines will take refinement to reduce the weight and dissipate the heat if they're arranged in a crowded way.

:D

>>4175885

I don't think steel is compatible with chlorate. Brass, bronze or any copper alloy certainly isnt. You will need something like titanium I think... Chlorate is a very strong oxidizer, and will form explosive copper chlorate with Cu and it might very well just eat through your steel tubing.

I'd advise looking into a perchlorate based propellant.

I hope you have a lot of money man, because this isn't going to go ahead if you dont :P

I commend you for your unconquerable spirit. Once again sheer stupidity wins out over common sense. I'm watching eagerly for the "I lost my hand" update.

>>4176153
Would be lucky to only lose a hand

bumpen

>>4174672
>2 wall thickness = pressure * diameter / yield stress
>Completely ignoring longitudinal stresses
Yet ANOTHER flagrant and potentially dangerous oversight... I think that makes, what, thirty now?

OP, at least make sure you're hiding behind something very solid and dense when this thing blows up (err, "launches"). Even in MY little rocketry forays (which were FAR more conservative and better-thought-out than yours), I still wound up with a couple explosions (one from the nozzle being improperly rammed, and another presumably due to a crack in the propellant grain). Of course, I was using cardboard casings instead of steel, so I didn't exactly have to worry so much about fragments tearing through my skin from 50 feet away...

>>4176124
The chlorate will only be in contact with the steel immediately prior to launch. Liners will be used and all tubes will be etched and packaged before fueling. If Al proves to be beneficial to the motor characteristics the fuel will not be mixed to be stored for any length of time, investing in using perchlorates for a metal mix is considered. Stainless steel, aluminium or possibly some form of composite tubes will be considered too.

>>4177995
>implying longitudinal stresses aren't half of circumferential and can't be ignored

What's worse is I haven't even considered the inevitable heating of the walls. They're rough estimates for now and I'll be hiding in a makeshift bunker far away from the launch pad.

OP you seem to spending a lot of time trying to convince yourself that this is safe. Launching chunks of metal into the sky is inherently dangerous. Try to get some perspective on the situation, you have a tiny piece of metal and you think you are going to launch a smart phone into space within a year?!!? Its just not going to happen. You can hack some far more safe and effective rocketry equipment off a few fireworks. I never thought I would be recommending multi-staging a firework for the sake of safety but I'm thinking of your family.

>>4178392

No where did I suggest this was at all safe but it's not impossible and there are a myriad of steps that can be taken to significantly reduce the risk.

why isn't this thread stickied yet?

An oxygen tank will be coming sometime after the christmas break following (hopefully) successful tests of a hybrid molded KNO3/Sugar motor using compressed air. Need to pick up a one way valve and a couple of other fittings before the motor can be tested

Was just thinking there that it's actually probably way easier and safer to just make a liquid engine. The entire rocket should be a LOT lighter than a bunch of tubes and the fuel will be way easier and cheaper to get. I can weld large tanks for oxygen and propane easily then just fill them with a few / whatever bottles. The plumbing and pumping will need to be housed in a section purged with nitrogen/argon/co2 and will need a reservoir for compressed gases.

Shit this is a way better idea.

>>4179615
Can anyone point me towards information about the compression of unconventional (not air) gases? Suppliers + info on pumps or generally everything to do with handling flammable gas.

I'm thinking retrofitting an air compressor setup will be sufficient but I'm also thinking the standard seals and ratios may not be up to the task of different gases.

Old refrigerator motors sound like they might be up to the task but right now I'm a little clueless

Yeah you could try and do all this cool, expensive but ultimately worthless stuff for science, or you could make a lot of money and then come back to science later on when a few thousand dollars is pocket money.

Pic related, dense but pretty good

>>4179615
Not easier and not safer... this is pretty much building a small missle. I bet it's going to be a bitch stabilizing and steering it in flight and all that.

I read somebody made a DIY cruise missle in NZ, but I have no idea how good it was or what it could do, but supposedly it worked. I think the guy was a mech engineer or something. The problem for this project will be getting resources...

I'm going to be removing this thread in a few minutes, it's been up for too long.

>>4180315
You're a mod?

>>4180315
What? Don't remove it yet. It will die when it dies. There is more progress to come!!!!

You are an absolute fuck if you remove it just for the sake of removing it.

>>4180308 Not easier and not safer... this is pretty much building a small missle.

lol, because packing 100 tubes with solid propellant isn't a small missile either. Controlling the direction is a problem faced with both type of rocket, at least with a liquid rocket you have the option of adding an emergency stop to shut off the fuel.

>>4180308 Sourcing resources

I can stock up on several ton of oxygen and propane much much easier than miscellaneous banned chemical powders

Can anyone get access to the NASA files on space technology? They only permit access to some stuff to official researchers

>>4180315
Too much science for /sci?

You want to build a rocket and make your own fuel tanks which will carry pressurized fuel and oxidizers next to each other, and then burn them probably less than 1m away from the tanks emitting an incredible amount of heat and then you want to stabilize it and steer it into space hoping it won't burn up before it gets there.

If you don't have some kind of engineering degree this will not fucking work... this will probably not work even if you do have a suitable degree for it.

>>4178392
What happens if it goes full retard and lands and/or explodes causing damage to people and property? You do not have the technology for this, the funding or the knowledge. You probably know this and you only came on here to get some attention.

>>4180669 Oh yeah sure I bet NASA will have a nice little PDF guide on how to build your own cruise missle.

If you knew anything about rockets with solid propellants you'd know that they're far easier to build and one was made in NZ that did drop a payload into orbit, but you don't... just no, OP, just no.

Why don't you build something small that can go a few hundred meters first instead of planning to build a suicide rocket.

a better idea is to launch it from a weather balloon, so it already is partially done.

>>4165346

That will never work for solid rocket. You've just created a motor with multiple throats. Shits gonna melt everywhere.

>>4180315
> it's been up for too long.
What kind of faggotry is this?
That's what the bump limit is for.

>>4180935
Thanks for (re)stating the obvious, but it's become blatantly clear that OP is a complete idiot, and isn't going to listen to anybody's advice.

>>4180949
There is a board for you, here you go friend
>>>/b/

>>4180758
>>4180935

Lol, both sections aren't going to be fired at the same time. End one fires then drops off as the next one fires.

>>4180758
What if I'm certified to ASME standards for high pressure vessels?

>stabilize it and steer it into space
Create a closed loop feedback system featuring tilt sensors to automatically correct the actuators on the gimballed nozzle system (note that a gimballed system is also much easier with liquid!). In this system, program basic goals and expected parameters then hope it goes where you want.

Launch it over the ocean...

>>4181339
Someone who had the funding, resources and expertise to do this project would not be giving a fuck what the ignorant numbers on /sci think.

>>4181339
Are you certified to build payload capable rockets? Are you certified to work upon Pressuried fuel rocket propulsion? What are you going to put on the front of it so it doesn't burn up leaving the atmosphere?

Just do it

>>4181414
>implying fucks given

>>4181414 What are you going to put on the front of it so it doesn't burn up leaving the atmosphere?

A condom

>>4181477


But srsly, a cone to survive leaving the atmosphere isn't a problem compared to everything else. It doesn't have to survive re-entry

Everything is moving ahead faster then I was expecting. I should be able to launch one of these rockets into space within a few hours. All I need is another small metal pipe and some sugar.

I calculate that if I double the size of the pipe I should be carry myself to the moon. But that will have to wait till next week.

ITT op is making a pipe bomb.

http://home.total.net/~launch/

Can buy plans for a liquid rocket motor for $21.95

Think they're worth it?

Gasoline

>practically finished budget for the week on christmas
>fuck

Spaceship!? What's going on in here?
>No parachute
>pipebomb
wtf stop this you'll lose a hand or some shit
<--- I do this naow

>>4182362
Don't need a parachute for space

>>4157086
No, absolute minimum is slightly above 21.9219757 mph (9.8m/s)

>>4182510
WTF am I reading?

>>4182525

that's the acceleration of earth's gravity you moron.

>>4182510
No, you're confusing acceleration with speed.
If you could have a compact-enough powersource and propellant, you really could climb out of the Earth's gravity well at walking pace.

how the fuck is this thread still alive? it's been up for nearly a week.

this is a great thread and op is an example to us all.

I wonder if this will be archived.

Christmas is getting in the way of progress

>>4184141

The we must KILL CHRISTMAS

>>4184596

Can we fit a reindeer tracking device so we're ready for next christmas?

http://www.youtube.com/watch?v=uDpbFsfOFnk