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Black powder rocket questions


JFeve81

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I've been making little 2 ounce cored black powder rockets for a little while now but have some questions regarding rockets in general.

 

The types of black powder rockets are cored, nozzleless, and end burning correct?

 

Cored has a clay nozzle and a cored fuel grain, nozzleless is a cored fuel grain minus the clay nozzle, and end burning has a clay nozzle but a solid fuel grain. right?

 

Out of those 3 types which produces the most thrust? Say you have 1 rocket of each type with the exact same heading. Which would lift it higher giving all things are equal. I'm assuming end burners because of the commercial Estes engines.

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Endburners can't lift much beyond their own weight.

 

As for whether a nozzleless core burner is capable of lifting more weight than one with a nozzle or vice versa will depend on who you ask. There are so many variables. The type of spindle and the fuel matched to it is a big one.

 

If you are interested in lifting nice sized headers, a traditional core burner tooling set in 8 oz or 1 lb is a great place to start (or end up). From there more aggressive tooling is available such as universal tooling, super bp, whistle and so on. It gets more complicated the further you dig in. But well worth it...

 

 

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Endburners can't lift much beyond their own weight.

Really ? Estes has been lifting rockets with them for years. What are you basing this tid bit of wisdom on?

 

As for whether a nozzleless core burner is capable of lifting more weight than one with a nozzle or vice versa will depend on who you ask. There are so many variables. The type of spindle and the fuel matched to it is a big one.

 

If you are interested in lifting nice sized headers, a traditional core burner tooling set in 8 oz or 1 lb is a great place to start (or end up). From there more aggressive tooling is available such as universal tooling, super bp, whistle and so on. It gets more complicated the further you dig in. But well worth it...

As a total newbee it amazes me you have so much experience to share . Why are these other rockets more complicated ? I am curious.

 

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I've been making little 2 ounce cored black powder rockets for a little while now but have some questions regarding rockets in general.

 

The types of black powder rockets are cored, nozzleless, and end burning correct?

 

Cored has a clay nozzle and a cored fuel grain, nozzleless is a cored fuel grain minus the clay nozzle, and end burning has a clay nozzle but a solid fuel grain. right?

 

Out of those 3 types which produces the most thrust? Say you have 1 rocket of each type with the exact same heading. Which would lift it higher giving all things are equal. I'm assuming end burners because of the commercial Estes engines.

 

Im not an expert but I belive as far as initial thrust the cored wins the day,for sound and takk off as well! Nozzeless which I have made on two do have a cool slow lifting sound as well with a lower pitch ,endburner I never made one

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well nozzleless based on the principle alone can lift more. E.G. see that cool charcoal tail in a nozzled rocket? that's wasted energy that could've been thrust
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Firebird snarks - "As a total newbee it amazes me you have so much experience to share . Why are these other rockets more complicated ? I am curious."

 

Simple traditional bp rockets can be hand rammed (up to the 1 lb size). That is, the increments can be consolidated using a rawhide mallet rather than using a hydraulic press. This is a very quick and easy way to make rockets and a good reason why many beginner pyros are drawn to rocket making. These BP rocket mixtures can be made using hand screened ingredients without requiring the use of a ball mill.

 

Would you like me to continue, my little stalker darling?

 

 

 

 

 

 

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JFeve, cored and nozzless rockets will produce the most thrust for your efforts. Nozzless uses a hotter fuel which gives more initial thrust, but without a nozzle it quickly loses efficiency of gas acceleration, whereas a nozzled rocket keeps more consistent thrust throughout the entire burn. Either type of rocket will lift a hefty shell. I suggest starting with nozzled rockets if you have not yet acquired the skill or equipment for making very fast black powder. If you're interested I have just finished a new article regarding how to make and use cored black powder rocket tooling: http://www.grassrootsdiy.com/?page_id=68
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JFeve, cored and nozzless rockets will produce the most thrust for your efforts. Nozzless uses a hotter fuel which gives more initial thrust ...

Not sure I understand why nozzle-less rockets perform well. I can't help observing that every practical rocket developed in the history of man, from the ancient chinese to the space shuttle, uses a choked nozzle.

 

Rockets are reaction engines, the fundamental principle of which is conservation of momentum - the momentum of the engine equals the momentum of the exhaust. You can increase this either by increasing the mass, or by increasing the speed, of the exhaust. Nozzle-less with a hotter fuel would work by increasing the mass. The alternative is increasing the speed by choking with a nozzle. The advantage of increasing the speed is that the kinetic energy of the exhaust is proportional to the square of the speed, so doubling the speed results in a four-fold increase of kinetic energy. Energy, in turn, relates to force and acceleration, so all other things being equal, a choked rocket will produce more thrust and acceleration from a given amount of fuel than nozzle-less. You can think of the nozzle as an impedance convertor, coupling the high pressure and low velocity of the burning fuel to the low pressure and high velocity of the exhaust. When the size and shape of the nozzle is such that these are matched on both sides, the transfer of energy is most efficient and the rocket will perform at its best. Design of the nozzle is, of course, rocket science.

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Would you like me to continue, my little stalker darling?

 

LOL! Your "Stalker" is an old snort and he is just razzing you and expecting you to come up with good reasons for your claims. Pay attention to him, he has lots of experience and has made inroads in this hobby.

 

Firebird, please tell us about your latest nozzless rockets, I understand that they do very well.

 

-dag

Edited by dagabu
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Hi Dag,

 

I'm away from home right now but I have a couple of videos I'd like to share on this topic when I'm back later in the week. We did a test of a 1 lb nozzleless 75/15/10 (mill dust) mixed with vaseline and a nozzled 70/20/10 (mill dust) mixed with dextrin. They each had 350 gr dummy headers and they performed equally. Both were on the red line. That was borne out by later CATOS. Oh, and they were UT spindles.

 

Here's my thinking and please tell me where I am wrong. The tube can only take X amount of pressure before CATO, right? So one could come up with any number of combinations of fuel mixtures and clay or clayless configurations that would work, right? That is until your combinations reached over the X pressure..? Or is that too simplistic?

 

There is a nice benefit to using the nozzled rocket we tested. It uses about three less increments of fuel than the nozzleless. And there is no nasty mixing involved.

 

I'm all ears.

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Firebird snarks - "As a total newbee it amazes me you have so much experience to share . Why are these other rockets more complicated ? I am curious."

 

Simple traditional bp rockets can be hand rammed (up to the 1 lb size). That is, the increments can be consolidated using a rawhide mallet rather than using a hydraulic press. This is a very quick and easy way to make rockets and a good reason why many beginner pyros are drawn to rocket making. These BP rocket mixtures can be made using hand screened ingredients without requiring the use of a ball mill.

 

Would you like me to continue, my little stalker darling?

Please do the more you talk the deeper the hole. I'll be happy to keep kicking dirt in the hole as your digging.

BTW take a look at when you popped on here and then look at when I did . How is it I am a stalker?

Next , Here you are showing just how little it is you know "Up to 1 # can be hand rammed" . Shoot I guess I need to tell the guy's hand ramming anything up to a 60#( BTW that is a 3 inch ID ) they have to quit since your wisdom says it is not possible to consolidate them properly .

So Back to the topic at hand . What kind of performance are you getting from your end burners ? What will they lift? What is the lifting ability of your nozzled and nozzless rockets in 1 # ? What is the spindle length difference between the 2 ? Green mix or are you ball milling ? What kind of coal are you using?

Floor is your's

 

 

 

 

 

 

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Go ahead and show me a 60# hand rammed motor. Hell, go ahead and and show me a hand rammed 6# motor for that matter. I'm not saying it can't be done, but who in their right mind is doing it? Let's see that thing fly.

 

And show me you can respond to a post correctly.

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Look up some videos of those enormous rockets from Thailand. They're all hand rammed for better or worse.
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Hi Mumbles,

 

I've seen those. And I suspect Firebird will come back to post about that hand ramming apparatus that I can't remember the name of right now. I get that.

 

Firebird, I'm a tyro. I've never put myself forward as anything but a tyro. But I do have tooling, I read and experiment to see the results for myself. A better use of this conversation would be for you to address my very generalized question about the max pressures that the motor tube can take. That will get us closer to answering the question of nozzled vs nozzleless.

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Go ahead and show me a 60# hand rammed motor. Hell, go ahead and and show me a hand rammed 6# motor for that matter. I'm not saying it can't be done, but who in their right mind is doing it? Let's see that thing fly.

 

And show me you can respond to a post correctly.

Not going to waste time with you I have shown enough to allow others to judge how your talking with out knowing . Funny thing about this hobby when you take advice from someone who has no idea what they are talking about you are likely to get yourself dead.

Man I would hate getting swatted by the Admin. LOL

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Hi Mumbles,

 

I've seen those. And I suspect Firebird will come back to post about that hand ramming apparatus that I can't remember the name of right now. I get that.

I think the term you are looking for is A Slide Hammer.

 

Firebird, I'm a tyro. I've never put myself forward as anything but a tyro. But I do have tooling, I read and experiment to see the results for myself. A better use of this conversation would be for you to address my very generalized question about the max pressures that the motor tube can take. That will get us closer to answering the question of nozzled vs nozzleless.

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Oh there's your post. A slide hammer. Yes.

 

It would be easier to see your hidden posts if you posted in bolded all caps.

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Oh there's your post. A slide hammer. Yes.

 

It would be easier to see your hidden posts if you posted in bolded all caps.

 

 

 

 

 

Maybe you missed this one too

Not going to waste time with you I have shown enough to allow others to judge how your talking with out knowing . Funny thing about this hobby when you take advice from someone who has no idea what they are talking about you are likely to get yourself dead

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Maybe you missed this one too

Not going to waste time with you I have shown enough to allow others to judge how your talking with out knowing . Funny thing about this hobby when you take advice from someone who has no idea what they are talking about you are likely to get yourself dead

 

I read that and have no idea where you are coming up with that. Maybe you could elaborate.

 

May I call you buttercup?

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Before any newcomers take my advice and "get dead" I would like to make this disclosure: ROCKETS EMIT SHOWER OF SPARKS. DO NOT PLACE IN MOUTH.

 

There.

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You'll put your eye out with those.

 

No, I believe that was a Red Rider that will put your eye out.

 

-----

 

I haven't had much luck with nozzleless BP rockets. Some guys with much more experience than I also noted decreased thrust when using U/H type spindles and a nozzleless BP motor. Even with milled BP with Alder coal, I wasn't able to get a flight with much snort with my tooling. It works fine if you ram a nozzle in though. My motors are still a work in progress, I'm not going to guess on lifting capacity to display height or write off any one technique just yet.

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No, I believe that was a Red Rider that will put your eye out.

 

 

had one for years and still have both eyes :)

-----

 

I haven't had much luck with nozzleless BP rockets. Some guys with much more experience than I also noted decreased thrust when using U/H type spindles and a nozzleless BP motor. Even with milled BP with Alder coal, I wasn't able to get a flight with much snort with my tooling. It works fine if you ram a nozzle in though. My motors are still a work in progress, I'm not going to guess on lifting capacity to display height or write off any one technique just yet.

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