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Black Powder Rockets


al93535

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I am suprised there is no BP rocket thread here yet. So here it is.

 

I have been making a few BP end burning rockets lately. I roll the tube 5/8" ID by 3 and 1/2" long. Although my newest ones are 4" long. I ram a conical shaped end plug, ram my fuel and ram another clay plug. After that I drill a 1/8" nozzle. These are end burning rockets.

 

The first picture is a pic of my rocket after it was fired. This was just a test to see what I can lift. The dummy header weighs 84 grams. The video of that test is right after the picture. I used 90% BP and 10% 325 mesh atomized al for fuel. I didn't get much of a tail. So I am now trying 80 mesh mgal 5%, and medium al flitters 5% with 90% BP.

 

The third pic is my newest working header rocket. It has 12 1 gram TI timed reports in it. The head weighs 75 grams. I have two more identical rockets on the way; a conkling blue, and ruby red.

 

http://img.photobucket.com/albums/v242/al93535/rocket.jpg

 

http://www.apcforum.net/files/MVI_0153.AVI

 

http://img.photobucket.com/albums/v242/al93535/rocket58.jpg

 

After these I will try adding ball shells and maybe multi breaks to the rockets. I might also try a bigger rocket, from 3/4" ID to 1" ID tubes.

 

Hopefully I will have more video's of these rockets soon!

 

Ooops, maybe someone wants to move this to the rocket area. Sorry!

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before the thread gets moved, did you mill your BP? Would the rocket be too fast if i used milled BP and CATO? thanks

 

nice rockets btw! :D

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For end burning rockets in particular, milled BP is what should be used. Due to the low burning surface area, you want a propellant that will burn "fast" to maximize thrust. If you use greenmix, usually enough lift won't be produced, so you can't have a larger payload.
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I use the fastest willow meal I can make. I milled for the normal time that I use for all my BP, 4 hours.
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Right thanks a lot, my BP is blasa milled for 4 hours so its fairly fast. My tubes should have dried out know so i think i shall try making some rockets. :D

 

Last questions I promise, could I use a roman candle delay mix for the delay between the burst? And how safe is it to drill out the cores of rockets if i use BP and Al? I have 300 mesh spherical aluminium of inoxia.

 

Thanks for the help

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I would drill it slowly, and if at all possible, by hand. One thing to note, if you are making core burners, use a slower mix. Since you seem to want to use BP, make an end burner. This means only drill a little bit into the BP. I also suggest just making the rocket component first before adding any sort of effect.
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Right thanks for that. I decided against adding a header until I am profficent at making these rockets! I hand drilled a 2/16th hole about halfway into the core.

 

I balanced the nozzle using the finger method (see pic) and added a peice of visco. The entire thing weighed exactly 10g... maybe too light?

 

Now all i need is for it to be dark :)

 

The rocket balancing on my finger: http://i81.photobucket.com/albums/j207/VonBass/IMG_0003.jpg

The rocket showing the nozzle: http://i81.photobucket.com/albums/j207/VonBass/IMG_0004.jpg

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I will be very interested to see your ruby red rocket, and if you can say how you make it it will be great. This formula warked for me only in stars, never was fast enogh as a rocket.

You use it for core less rocket?

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I am sorry. I meant conkling blue and ruby red stars in the header. I only use BP in the rocket engine.
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From the competition thread:

 

 

 

Ok here is my first submission, with more to come. This is a 6 ounce bp end burning rocket with my variation of ruby red stars.

Stats:

engine:

41 grams

1/8" nozzle

4 inches long

5/8" ID

 

Header :

83 grams

2" cylinder header

fused with visquick with no other delay

 

The stick was 32".. No attempt to balance this rocket was made. I learned is is not needed. In the video the rocket heads into the wind, its not from the balance on the stick 2smile.gif See my test video for that.

 

Total rocket weight 136.4 grams (with a 12.4 gram 1/4" diameter round stick)

 

Pre firing picture:

 

http://img.photobucket.com/albums/v242/al93535/rocket58.jpg

 

Video:

 

http://www.apcforum.net/files/6OZrubyred.wmv

 

 

And rocket: I launch from an old metal tube from a ripped up tent. Just push it into the dirt and I am ready to go.

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Thats a beauty! I especially love the sound of rockets :)
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I ca't belive this little motor, with no core, can lift so much with it. amazing.

 

And

with my variation of ruby red stars
. what is the different between the original comp and your stars?
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I have 3/4" tooling here, I just need to roll some tubes and such before I can be making some rockets. I heard somewhere that 3/4" rockets can lift something like 180g? This is for a core burner (tooling is from www.pyrotooling.com so its a core burner). Has anyone had experience with 3/4" rockets and can enlighten me?

 

EDIT: Just rolled a beast of a tube; 3/4" ID x ~7". Walls on it are around 4mm. Sorry about the shithouse pics but my digital camera is out of arms length, therefor I can't be arsed getting it.

 

http://img.photobucket.com/albums/v466/mephistosminion/Picture237.jpg

 

http://img.photobucket.com/albums/v466/mephistosminion/Picture236.jpg

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I just can't anderstand how you can lift so much with this endburning rockets :blink:

 

I made today some test for my tools for 1/2" core burning rocket and 3/4" for fountain/driver.

 

The first test was a 1/2"rocket. 4.5 m"m spindle DIA (3/8*ID), 3.6 c"m long (3*ID). I put a pyload of 25 grams of dirt on top of it to chack it's lifting power.

 

http://img181.imageshack.us/img181/6107/first05inchrocket25grpayload5v.th.jpg

http://www.apcforum.net/files/first0.5inch...25grPayload.wmv

 

It fly to about 15 meters I guess. but it's dont very good if I want to lift with it stars and not only flash (they can come back to the ground in this height).

Does 25 gram payload for a 1/2" core burning rocket is too much?

 

 

Also I made a end burning 3/4" rocket, spindle DIA IS 5 m"m (1/4*ID) and about 21 m"m long (just to pass the plug).

 

this rocket did fly, but only to about 1.5-2 meters and came back to the ground:

http://img283.imageshack.us/img283/5527/075inchendburningnopayload6fa.th.jpg

http://www.apcforum.net/files/first0.75inc...g_nopayload.wmv

 

Is this a balancing problem? (I dont balance my rocket, never.) or does it got not enogh thrust?

 

Thanks.

 

[edit]

More pics of the rockets:

1/2" autopsy:

http://img283.imageshack.us/img283/6668/05inchautopsy7ni.th.jpg

 

3/4" autopsy:

http://img283.imageshack.us/img283/3607/075inchautopsy6lf.th.jpg

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The nozzle diameter on your 1/2" rockets is too large. The case is also not long enough. This would cause it to no provide a lot of thrust, which could explain the low height. What fuel did you use in each of these? It may also have an impact
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3/8 the ID.

I also wrote 4.5 m"m for clarification. (wich is 0.2 m"m smaller than the one passfire used)

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Sorry, I got confused by the way you said it. I thought the nozzle was 3/8". Your casing is still about 20% too short though.
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here a drawing of what I think will be the rocket with the most thrust:

 

http://img271.imageshack.us/img271/2694/scatchrocket6lq.jpg

 

All the fuel uper than the spindle got the same thickness as the fuel in the sides of the rocket. (the drawingis much more understood)

 

So if this true my rocket had the most thrust I can get from it with this spindle. Is this sure this is the best measurements if it was at passfire?

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I understand the drawing. Out of curiosity, what makes you think that will provide the most thrust? The general convention is to put a solid increment equal to 1 to 1.5x the ID of the tube. This is roughtly 2-3 times what you have in your drawing.

 

The size of rocket you are making, actually a 3/8" or 2oz rocket is a weird one. It uses a shorter tube, and a different size nozzle than all the other BP rockets.

 

My best advice would be to launch some without payloads. This will tell you if it is your rocket, or just the weight of the payload.

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Just thought I should share my work-pony:

 

The rocket engine is made in a 50-55 mm long electrical PVC tube; 14mm ID.

 

First, a 15 mm bentonite clay nozzle is pressed.

Then 25 mm of 70 KNO3 / 30 BBQ-C (milled) is pressed.

After that a 10 mm end plug is pressed.

 

A core is drilled with a 3 mm drill bit for a length of 35 mm (allmost completely trough the BP).

 

 

These rather small engines are used in a stick type rocket using a 500 mm plant stick taped to them.

Without payload, these go completely out of sight and are rarely recovered.

 

I've tested with dummy payloads up to 25 grams (estimate heights):

 

1 gram => 50m-70m at least

2,5 grams => ~50m

5 grams => ~30m

10 grams => 15m

25 grams => 5m

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