Alt innom Rocketry

[esa]

Thanks for the tips

 

And, yes the Space Shuttles must be handled with more care, but they are almost past their expiration date. They are replacing the Shuttle (made in the 80's) with something new. Although I don't know what with, but it is there is going to be quite a bit of new plans for NASA and ESA. Going to the Moon and Mars, and being more overall active then they have these past few years. Time to put the plans into action, pretty much.

 

esa

[esa]

Now I am finished with most all my final tests in school. So now I am going to start construction of some rockets.

I think I will start out forming a mold, out of pvc plastic (by using coolant fluid used in car radiators because there boiling point is just over the pvc plastics melting point; thus making it easy to form). But before that, I think I will start with buying propellant. I need to get ahold of potassium nitrate, KN03 (kaliumnitrate). Does anyone know where you could buy this stuff? Like at a pharmacy or something...

Then I need sugar, which I have, of course (although how big of a role does the molecular structure of sugar have? I know that there are different types of sugar).

 

Maybe there is something else someone can reccomend for propellant, but I think KN03 will work best. I just need to know where you could get some...

 

esa

[varmit]

You can use melis to,because it's much better to melt.

Someone add a little bit sulfur(=er svovel trodde jeg),but this is no need.

you can also buy rocket engines if you want

[esa]

You can use melis to,because it's much better to melt.

Someone add a little bit sulfur(=er svovel trodde jeg),but this is no need.

you can also buy rocket engines if you want

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Melis hmm? Do you have a site with some info on it?

I also know that sulfur is used in rockets, (mostly in fireworks I believe...), and I have bought rocket engines before. However I need to find rocket engines that exceed the first class, A/B/C, I need something more powerful if I were to buy rocket motors. It is also hard to get bigger ones, especially in Norway, and I think you might need lisences for big ones

 

But does anyone know where I could get KN03 (potassium nitrate; kaliumnitrat)?

 

esa

[Nedward]

You can get KNO3 at the drug store. It costs about 100,- for 90 g. Or, you can order it from www.kno3.com (it looks like a scam, but acording to users of freakforum, it is reliable)

 

You can also buy sulphur and charcoal there, that way you can make black powder fuel.

 

I think you can buy KNO3 at "felleskjøpet" too, the name on the produc is "Krista-K plus". I am unsure if it is pure enough to be used with "melis". And the price, well I don't know.

Endret 15. mai 2006 av Dj_eLmO

[varmit]

Beklager at jeg skriver norsk,men skal være kort. du får kjøpt 25 kg "kno3"(mer en ren nok)på felleskjøpet ,til ca 200kr.

skal også snart komme med en link til gode og proffe motorer,det er ikke problem å få kjøpt helt ned til M-motorer nesten.

[esa]

(taken with my cell phone, btw)

 

I have bought 90 grams of potassium nitrate (KNO3) and have already tested it using powdered sugar (melis) and then trying regular sugar.

 

I have found out that powdered sugar (melis) was too fine of a grain, and didnt 'burn' all that much. Then I went over to regular sugar, using half a teaspoon of each (ca 50/50), then saw a way bigger flame. (I was thinking that it wasn't going to be such a big flame, but it was huge compared to the powdered sugar, hahaha! It was a little scary moment there, surprising how only a teaspoon of propellant could produce that much energy).

 

Anyway, I think I will try to buy KNO3 at felleskjøp instead of a pharmacy, because it is too expensive (100kr for 90grams) and I would rather buy 25 kg for 200 kr. Although if you buy it at felleskjøp, would it be the same type of grain?

 

Now I just have to start constructing rocket casings, either out of pvc plastic or some sort of other material. Pvc I have heard is good to use, but does it splinter when it breaks or fail under heat?

 

Btw you don't have to talk english, I understand norwegian pretty well, its just easier for me to talk english. I hope you guys can understand most of what I am saying.

 

P.S. Where could I buy some rocket motors? Like anything bigger then ABCD motors?

 

esa

[varmit]

Du kan jo sjekke litther

[esa]

Du kan jo sjekke litther

6156831[/snapback]

 

Impressive rocket motors, but maybe a little too advanced and expensive for me now, lol I need something that is a little more simple, but not too simple. Plus I don't think they would ship it to Norway. They must ship rocket motors by ship, not plane. I need to find a place where they would sell rocket type stuff, but I don't know any stores here that do...

 

Thats why I am 'building' my own rocket motors, anybody have previous experience with rocket motors?

 

esa

[varmit]

Ok I see.....Enklere motorer? Men du kan jo bare bygge dem selv også

[GolfBag]

De som har fått laget dyser, motor osv... kjenner dere personer som jobber på mek. verksted eller er dere bare litt handy-men.

[esa]

Ok I see.....Enklere motorer? Men du kan jo bare bygge dem selv også

6160619[/snapback]

 

Haha, simple as in not being so "powerful" ('too' explosive). I don't want to start with really big rocket motors, just advance from ABC motors to DEF motors, etc.

My main interest is to actually build the rockets myself, but I could also buy one if I'd like (although it would have to big more powerful then your average rocket).

 

I need to experiment/ find out what to use to build the rocket, while also not blowing myself up I should have some clue by next week I hope

 

esa

[esa]

Ok, I need to try to find a thermostat cooker (for casting of the propellants). Does anybody know where I could find/buy one here in Norway? It is electric and needs to measure the heat accurately with a "built-in" thermostat.

 

Here is an example of one:

 

"Presto Multi Cooker"

 

esa

[Zethyr]

Prøvd Claes Ohlson eller Jernia? Der ville jeg sett etter dem om jeg selv skulle hatt en hvertfall..

[kyrsjo]

Kansje det er en idé å bruke gassbluss+rel. tynn panne (el.) (rask reaksjon), pluss en form for eksternt termometer (IR er vist det beste og enkleste)?

[esa]

Kansje det er en idé å bruke gassbluss+rel. tynn panne (el.) (rask reaksjon), pluss en form for eksternt termometer (IR er vist det beste og enkleste)?

6256951[/snapback]

 

No, I need something that is accurate and effecient (something that I don't need to "worry" about). I'm pretty sure I could get ahold of a thermostat cooker, going to look at Claes Ohlson or Jernia; which Zethyr suggested.

 

esa

[esa]

First design stage of my (KN/SU) rocket:

 

 

*example sketch

 

esa

 

EDIT: Be sure to see actual pixel size...

Endret 7. juni 2006 av esa

[kyrsjo]

Kansje det er en idé å bruke gassbluss+rel. tynn panne (el.) (rask reaksjon), pluss en form for eksternt termometer (IR er vist det beste og enkleste)?

6256951[/snapback]

 

No, I need something that is accurate and effecient (something that I don't need to "worry" about). I'm pretty sure I could get ahold of a thermostat cooker, going to look at Claes Ohlson or Jernia; which Zethyr suggested.

 

esa

6257275[/snapback]

 

Joda, men har en følelse av at "termostatkoker" på Claes Ohlson (hold deg langt unna Jernia, drittbutikk) kansje ikke er supernøyaktig.

[Nissen]

Noen som aner (evt. klarer å regne ut) hva som er det optimale forholdet mellom den indre diameteren til motoren og hullet i dysa til raketten?

 

Er det slik at rakettmotoren består i hovedsak av et røyr som tettes i toppen ved hjelp av en propp, som også har dyse i den andre enden, og drivstoffet fylles i motoren ved at en tar ut proppen og heller nedpå med kno3 / sukker mix'en i selve røyret? Har jeg forstått det riktig?

[esa]

Noen som aner (evt. klarer å regne ut) hva som er det optimale forholdet mellom den indre diameteren til motoren og hullet i dysa til raketten?

 

Er det slik at rakettmotoren består i hovedsak av et røyr som tettes i toppen ved hjelp av en propp, som også har dyse i den andre enden, og drivstoffet fylles i motoren ved at en tar ut proppen og heller nedpå med kno3 / sukker mix'en i selve røyret?  Har jeg forstått det riktig?

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Hm, where to start...

 

Well first of all this is how a rocket "works":

 

*very basic concept

 

Then here are some different stuctures of the propellant (oxygen + fuel) in the combustion chamber of the rocket motor:

 

*the most common types

 

*other examples

 

To create these structures you would need to "melt" the propellant togethor, or use some sort of "binder". The most common type of propellant used for model rockets is the KN/SU type, which is KNO3 + C6H12O6 (sugar). For this type the easiest option is to "melt" it...

 

Here is a picture showing some common terms used in rocketry:

 

The nozzle size can vary, but is "usually" 1/5 of the grain diameter. It depends though, some can be 1/3 of grain diameter. Size, propellant, grain structure; all play a role in the calculations of the nozzle. The "hollow-cylinder" type grain (as in picture above), should have a core area that is twice the size of the nozzle (throat area)...

 

The KN/SU mix should be a 60/40 mix, some say its better with a 65/35, but it depends on the particle size of the grain and the different pressures/temperatures its being used in...

 

Anything else you need to know?

 

*If you are considering building a rocket, I would reccomend you learning as much about it as possible before you actual try. Even though KN/SU is not easy to ignite, it is very very dangerous (as I've said so before). There are of course many other "dangers" of this, but I presume that you've heard it before and realise the risk before actually constructing a rocket.

 

esa