Few rocket Beginner questions

Hi all
I am new to this forum so please be gentle
I am working on my new rocket (v3 after v2,v1 both failed)

Some info:
Rocket body is cardboard tube
19.5" length
1.5" diameter

Fins: balsa wood

Engine:
Candy propellant 3 part (home made)
each part is 1.5" diameter about 3" height
total engine length is like 8" to 9"

I molded the propellant into same cardboard tube in a way It can exactly fit the rocket body tube.

Sorry for the mass of questions,

what is my engine size? Is it ok for this rocket size?
Why do I need to make core hole in my motor?
Is it possible to drill small hole in the engine and insert small birthday sparkler without the core hole?
What is a recommended material to build the nozzle? (epoxy, gypsum cement?)
What is a recommended material to cover the motor top part in the rocket body?

Thank you very much!
Sharon

Ms. Sharon,

First welcome!!

I manufacture rockets, I 'm gonna try to help you.

As for your Rocket I suggest a quick search for "Open Rocket" (freeware I think) Or "Rocksim" It's available at Apogee's website. Either will provide you with the tools you need to Build a successfull Rocket.

To the questions regarding your propellant. STOP!:y:
Anyone can make R candy, That said It does not mean they should!!!
The amout of fuel you are decribing could very easily Blown your hand off or worse!!!!!



Please, Please, Please
Go to Jimmy Yawns site regarding Rocket Candy, Tons of great info.
Also, Look up Richard Nakka on your search engine.
I highly recommend you get to a Tripoli club near you if you want to make experimental fuel.

Take the steps and do it right!
Read Everything, Before you start down the wrong (very dangerous) road.
I want you around to enjoy our great Hobby!! Heck, I hope to sell you a kit!!!


Peace, Love and Happiness

Stephen Eric Foster,
BaddAzz Rocketry

I am so glad I have money and am lazy ! :roll:

Sharon,

I won't answer any of your specific questions, because most of what you are asking concerns experimental propellants. If you are *not* a L2-certified Tripoli member, I have no proof that you have the skills necessary to not blow yourself up.

1) If you are posting here, I assume you have access to an Internet-connected computer - download OpenRocket and build your rocket design in software first.

2) Join Tripoli and find a local club to launch with.

3) Build gradually larger and larger rockets as your comfort and confidence grow. Use commercial motors, black powder first, then work up to APCP.

4) Certify HPR L1 by building, flying and recovering undamaged a rocket powered by a motor of H or I impulse (aside from sparky motors which cannot be used for certification).

5) Certify HPR L2 by first passing the Tripoli L2 Test, then building, flying and recovering undamaged a rocket powered by a motor of J or K impulse.

6) Then participate in experimental propellant motor building.

G.D.

I wouldnt try candy propellant first. Start with the estes engines and them move to higher ones. Get a L2 then mess with Kno3 as much as you want. Also learn as much as you possibily can about Kno3 before trying it. Remember, you do put your life on the line by making Kno3 motors.

How did V2 and V1 fail? This info is important if you want us to help you.
Good luck,
Alex

Aksrockets said:

I wouldnt try candy propellant first. Start with the estes engines and them move to higher ones. Get a L2 then mess with Kno3 as much as you want. Also learn as much as you possibily can about Kno3 before trying it. Remember, you do put your life on the line by making Kno3 motors.

How did V2 and V1 fail? This info is important if you want us to help you.
Good luck,
Alex

Click to expand...

Good Advice Everyone.
For the Record the Nakka site is down for a while, he's moving and having to change servers etc.

Sharon,

It is going to be extremely difficult to contain the internal pressure of a working rocket motor with a cardboard tube. You are going to need much stronger structural materials. (I'll bet part of your first and second failures were the whole rocket bursting into flames?)

The Nakka and Yawn websites are definitely the place to start if you want to work with "candy" motors, but you can also start with the basics in order to learn about stability, basic propulsion principles, and performance. An Estes starter set will get you all you need to make some preliminary launches, and it won't cost nearly as much as you are going to spend on making sugar motors.

What part of the country do you live in? If you can give us some general idea we can probably help you get in touch with some experts near you, to give you some personal coaching---

Rocket_Man said:

I am so glad I have money and am lazy ! :roll:

Click to expand...

I resemble that remark :roll:

I have no idea what is Tripoli club,
I don't live in the USA (yet),
I am old (35) and experienced enough not to blow myself,
Do I have to be club member to post questions?
If the answer is no Please try to help with my questions

Thank you!

the answer is that unless you are a member of the NAR or tripoli, and in the united states, there is no way you should be able to get information about experimental rocket motors from this site.

you can talk about rockets all you want, but propellant formulas are out of the question.

beyond that, you really need to start with manufactured items. what country do you live in? try to find out if your country has a national organizing body for model rocketry, and if not, then find out the laws governing it. other than that, you really can't ask quesitons about propellants.

other than that, go to tripoli.org if you want to know what it is, though it only applies if you live in the US.

though you don't have to be a member of a club, you do have to know that research rocketry is not spoken of here except in the research forum, which is off limits to anyone not meeting the requirments, one of which is being in the US.

edwinshap1 said:

you can talk about rockets all you want, but propellant formulas are out of the question.

Click to expand...

Thank you for your answer,
I didn't ask for a formula, the engine already made

I am asking simple measurement and body size questions,

edwinshap1 said:

national organizing body for model rocketry

Click to expand...

NO that I know of

powderburner said:

Sharon,
...difficult to contain the internal pressure of a working rocket motor with a cardboard tube
You are going to need much stronger structural materials

Click to expand...

Well PVC is much heavier then cardboard tube,
The engine is molded into cardboard tube that fits the main cardboard tube
so its actually double (4 time thicker then toilet paper cardboard tube)

well i think that a couple of the questions are okay to answer.

the problem is that we have no idea how strong your propellent is, and since you don't know what size nozzle you're using, that adds another engineering variable. the only way to know the total impulse of your motor is to do a test burn on an impulse meter.

the need for a core hole is that certain types of propellents burn faster than others (black powder is fast, KNO3 and APCP are slow), and to get the same thrust from different motors, they need different configurations.


and i wouldn't use a sparkler to light it..

and i wouldn't use a sparkler to light it..

Click to expand...

15 cm sparkler (5.9") is not safe enugh?
It lights for for about 10 seconds..

regarding the size of the nozzle - I was hoping you can tell me what size i need...

The standard for igniting rocket motors is to use an electrical system. It is more reliable and safer. It also allows you to abort the launch if something happens that makes launching dangerous such as a small airplane suddenly fly into your airspace. If you light a fuse or sparkler you can't abort once you light it.

It will really help us if you tell us what country you are in. We have a number of non-U.S. members and they might be able to give you specific guidance based on the laws of their country.

Zeus-cat said:

The standard for igniting rocket motors is to use an electrical system. It is more reliable and safer. It also allows you to abort the launch if something happens that makes launching dangerous such as a small airplane suddenly fly into your airspace. If you light a fuse or sparkler you can't abort once you light it.

It will really help us if you tell us what country you are in. We have a number of non-U.S. members and they might be able to give you specific guidance based on the laws of their country.

Click to expand...

More than being the standard, it is the rule. The Model Rocket Safety Code specificly states that all model rocket engines must be ignited by electrical means, with a launch controller meeting specific design requirements.

Is this a test? You all realize that Sharon could resemble this guy:


Faisal Shahzad

Just sayin.....
Even if this is an honest request, do you really want to encourage someone to enter our hobby with experimental propellant? :no:

Ok, I accept the air space safety issue, aborting launch is critical.
I will work on electric igniter (I have old 6v battery and the materials, I will check if the battery still have any capacity left..)

I still have some questions open:

• What materials do you recommend creating the nozzle?
• Should I close the top part above the engine? What material will stay firm on the cardboard?
• What size hole for the back nozzle this engine size?
• Is iron washer necessary for this setup?
• Is 12 deg ok for the back nozzle?
• What it the recommended angle for the internal convention chamber?

Wayco said:

Is this a test? You all realize that Sharon could resemble this guy:
:

Click to expand...

This is a small cardboard rocket you moron,
I didnt ask any recepies, Just general body recomendations

Get a life:bangpan:

op:

I have a life, thanks. And I might be saving yours if you light experimental propellant with sparklers...
Here is what we're talking about:
https://www.youtube.com/watch?v=OxmZvttZf0k&NR=1&feature=fvwp

Sharon,

Since we cannot discuss the specifics of your "formulation" and "process" of how you make your motor. We cannot help you. Those are both the key ingredients to make it successfull.
Nozzle material, is typicaly in hpr EXperimental motors, made of Graphite. mostly our cases that contain the propellant made of 6061 aluminum, with the graphite as the nozzle(aft closure), and a machined aluminum bulkhead as the forward closure.
Generaly, the propellant is cast inside of an ablative liner so that the metal case is not damaged by the burn, *craft paper*, and the hardware of our motors are mostly resuable.


for aerodynamic simulations i use RASAERO.com. download the software and it works great.
you can download this handbook, if you want to understand how RasAero comes up with its formulations for how it works (along with the RASAero manual) you can read these...


https://www.privatedata.com/byb/rocketry/Documentation/mil/CI-762-MH-4995-1033.pdf

https://www.grc.nasa.gov/WWW/K-12/airplane/ienzl.html

this link has a nozzle flow simuation.

as you can see the variables (physics) that dictates the nozzle, are dependant on your "propellant" formula, density, heat... ect...
wich generates pressure. and thusly thrust when accellorated through the nozzle.

Since your "motor" is entirely unknown. we cannot help you with specific answers. theres a nightmare difference between retaining 50psi at ambient temperature, as compared to 1000psi at 3,000 degrees.

physics, was developed in large part outside the us. So, no mater where you live. you sould be able to find something. that pertains to making rocket motors.

In short, no one here, can answer any of your questions.

So if Clay D's "Incomprehensible Content!" is confusing, let me dumb it down to my Moronic level. A cardboard tube with a steel washer ain't gonna do it!
Hey, we tried to be gentle.....

OK, I'll try to be a bit more polite, but I have to agree with others that think this is a bad idea. Based on your OP, it appears that you are new to the hobby. Maybe this is an incorrect assumption, but some of the questions point to that. As such, you really need to step back and realize that what you are dealing with is literally rocket fuel...it is not a toy. It is dangerous and can cause great property and bodily damage if not handled properly. Also, judging from your questions, it appears that you have done minimal research on your own regarding the science and engineering of building a motor. While forums such as this are great resources for getting helpful advice, I would never consider using one as my primary source of instruction, especially for something as potentially dangerous as what you are doing. It would make more sense to me, and would be much safer, if you first found published literature, scientific papers, etc. on the topics. Then, after having gone through those carefully, use forums like this to ask questions where you may need some clarification of what you have already researched. Having said that, this particular forum, for various reasons, has strict rules regarding discussion of experimental motors.

Another thing to consider when looking at some of these responses which are confrontational, is that you are dealing with people who are passionate about this hobby. There are a lot of ways that the government can make it difficult or impossible to enjoy this hobby. National organizations like the NAR and Tripoli work very hard any time federal or state governments are looking at modifying or making new regulations that might affect our hobby to ensure that we are able to continue participating in something that we love. As such, one of the largest tools these organizations have in their favor is the safety record of rocketry. But all it takes is one or two accidents caused by an individual or individuals doing things like you are attempting to hit the airwaves and suddenly clubs lose their flying sites, and local or state fire marshals start looking at rocketry in a negative light. Before you know it, regulations are passed where you either cannot launch rockets at all, or at best you need to jump through hoops of red tape to get some permit to be able to legally launch rockets.

That's not an apology for some of those posts...just an explanation of why they are there. It literally only takes one bad apple to destroy years of work by these organizations. You may think that the only one you are putting at risk is yourself and why should any of us care. And while you may be the only one in physical danger, you are potentially putting the hobby in danger, and as such, affecting quite a large number of people besides yourself. It may not seem like one person doing something like this can have that large of an affect. But it can and does happen. I too would strongly recommend that you start out with manufactured motors, which are built to very strict safety standards and go through significant testing and certification. Learn about how they work, why they work, and learn how different thrust curves affect the flight profile of different sizes and styles of rockets. Then, with the correct research and preferably under the guidance of people in some organization like Tripoli that have the knowledge and experience, you might try making experimental motors.

Hi Gness guy
Thank you for the polite and detailed answer
You have a basic assumption wrong; I don’t live in the USA so:
>> done minimal research on your own regarding the science and engineering of building a motor
I am trying, our country is not so developed in this area (hobbywise) so I can go to an organization like NAR and Tripoli and get resources.
My source for education is the internet/YouTube


>>>>It literally only takes one bad apple to destroy years of work by these organizations
This is irrelevant since as I said before

>>>have done minimal research on your own regarding the science and engineering of building a motor.
I am trying, this is a begginer forum isnt it?

Folks, since you are all so suspicious about the “Experimental” engine,
And since you cannot discuss the specifics of your "formulation" and "process",

Please do not answer my question!
Moderatorplease please lock this thread

Thank you very much.

Sharon whipple said:

Hi Gness guy
Thank you for the polite and detailed answer
You have a basic assumption wrong; I don’t live in the USA so:
>> done minimal research on your own regarding the science and engineering of building a motor
I am trying, our country is not so developed in this area (hobbywise) so I can go to an organization like NAR and Tripoli and get resources.
My source for education is the internet/YouTube


>>>>It literally only takes one bad apple to destroy years of work by these organizations
This is irrelevant since as I said before

>>>have done minimal research on your own regarding the science and engineering of building a motor.
I am trying, this is a begginer forum isnt it?

Click to expand...

Where in the oblique sphere are you located?
Rocketry is pretty much a 'globaly' aquired knowlege. Albeit internet and youtube are overal poor for resources, I can atleast grasp what you were getting at.

Funnything about the associative crones, is that they willfully and deliberately forget, one bad apple within thier safetycode, doing something bad, is far more damaging to thier credibility than you are on here looking for answers. Maybe they just frogot to point it out, they do fine at not fully enforcing the "safety" of the code and hurting-or almost hurting.. on thier own.
(I dont chose to forget where it was i started in rockets)

Likewise, I can attest there is great benefit as relates to associating with other rocket people. Being associated, lets me fly much BIGGER and MUCH MORE POWERFUL rockets than I could ever "safely" do on my own.(not to mention i couldnt get a waiver to legaly fly the rockets i do.)
Although, i aslo wont fail to point out, exposes me to the dangers of others errors...

I would start searching for any book you can find on making rocket motors. (even on the internet - amazon.com). you will get a consistant and conciese presentation of the material in a book, over chopped undiscernable information -misrepresented misinformed and misguided-* infomration on a forum.

*as i am often accused of... and good luck...

Sharon whipple said:

Please do not answer my question!
Moderatorplease please lock this thread

Click to expand...

Done.