Comets

[mormanman]

Has anybody ever tried this comp?

 

White comet #1

Source: rec.pyrotechnics

Comments:

Preparation:

 

Potassium nitrate.................................96

Fine charcoal.....................................44

Sulfur............................................15

Dextrin...........................................10

 

I made a batch of 1" comets with +7 (-20 +40) Ti flakes (from Bob) for added effect. I don't think these will need any prime, but how about burnrate?If they are fast burning I guess I should wrap in kraft so only bottom ignites, otherwise fire as is?

I won't be able to test anytime soon though...

I've made stars like that and they were pretty nice. They were actually white.

[Bonny]

I have some 1-1/2" ID cardboard tubes I would like to use to fire comets. For a pump I have a pc of SS pipe that has an ID of about 1.360". That would only leave me a little over 1/8" clearance, will that be OK or is the fit too tight. I will bottom fire if needed to avoid QM down the side...

 

edit: Just noticed...200 posts not a pyromaniac anymore

[Mumbles]

If you're side fusing, it should probably be alright to fire out of. I would try to keep it clean though to prevent any opposition to it moving out of the tube. I've blow a few tubes up in my day because I haven't cleaned them out.

[Bonny]

I will most likely be side fusing (that's what I meant by bottom firing ). Maybe some wood hardener to help strengthen the tubes would be a good idea?

[psyco_1322]

qwezxc12 you were making your comets a half inch smaller than the tube, did you make up that space with something? Just wondering what your clearance was. You should be able to have more clearance on bigger comets than little ones like 1.25" right? I tryed launch and small one the other night and it failed to obtain any reasonable altitude. It was really a star that I was testing but it wouldve been like a comet if I had called it that.....so yah....im done.....

[qwezxc12]

psyco,

 

The small comets were made with a 1-1/2" comet pump that looks just like this only larger in diameter:

http://www.skylighter.com/images/web_pictures/thumb_tl3114.jpg

I shoot them out of a 2" HDPE mortar. The extra space is made up with the QM leader and the rim of a 1/2oz. condiment cup as seen here:

http://www.apcforum.net/files/Comets3.jpg

 

I explained the 3" comet pump dimensions to mormanman a while ago in the random thread:

 

"I specifically bought a 2.5" rammer and a piece of 2.5" schedule10 pipe that had an ID of 2.63" for a sleeve. So my rammer has .065" clearance and won't bind in the sleeve, and the finished comets have a clearance of .187" in a 3" mortar, which is perfect and leaves me a little room for paste-wrapping the comets with a few turns of craft.

When I refer to it as a "3in comet pump", it's meant that it makes a comet that is fired from a 3in mortar...the same way a 3" shell doesn't really measure 3" OD. The actual hemi is more like 2 5/8", but we call it a 3"in shell because that's the mortar that the finished shell is fired from."

 

Hope that answers your questions.

[psyco_1322]

OK, I see. Thanks.

 

Just been wondering about that pic, whats that paper about that its sitting on?

[qwezxc12]

OK, I see. Thanks.

 

Just been wondering about that pic, whats that paper about that its sitting on?

It's a build sheet...I usually make a lot of shells over a few weeks/months for a shoot. To keep track of everything, I make a spreadsheet to detail the shell, comet or mine type, what type and size of stars it might contain, the weight, lift amount, rising effect, etc...

That way when it's dark and your shooting a box full of shells you may have made a month previous, you can say, "#23...let's see, that's a 4" Emerald Green with Win39 pistil and a Mg rising comet".

 

IIRC, That sheet had some 3" comets to salutes at the top, some 3" D1 shells and a series of color comets.

[psyco_1322]

Ah, gotcha. Not a bad idea there, guess it just organization.

[Chris]

OK, I see.  Thanks. 

 

Just been wondering about that pic, whats that paper about that its sitting on?

It's a build sheet...I usually make a lot of shells over a few weeks/months for a shoot. To keep track of everything, I make a spreadsheet to detail the shell, comet or mine type, what type and size of stars it might contain, the weight, lift amount, rising effect, etc...

That way when it's dark and your shooting a box full of shells you may have made a month previous, you can say, "#23...let's see, that's a 4" Emerald Green with Win39 pistil and a Mg rising comet".

 

IIRC, That sheet had some 3" comets to salutes at the top, some 3" D1 shells and a series of color comets.

I do the exact same thing. I have records from years back. It is a really good way of keeping track on what's where. I also write down results for each device. That way it is easy compare results for different devices. This also helps tuning in every aspect of a device in future.

[Bonny]

I'm looking for a good KClO4 based FAST BURNING comp for a matrix comet. I want to make a comet loaded to the nuts with dragon eggs and would rather not use a nitrate based one.

Or better yet, what would be a good way of making a comet almost entirely out of dragon eggs?

I was thinking of a "cut star wet" (redgum bound maybe?) comp lightly pressed into a toilet paper tube that would be torn off after drying.

Any ideas anyone??

[psyco_1322]

If your matrix comp burns up too fast it will lend you with more of a star mine effect. You could just take a cup of dragon eggs and dump some slurry in to turn it solid but I think you might get the mine effect then. In the case you want that effect, a mine would be simpler. I would suggest trying just a straight KP replacement in a bp formula. So 75:15:10, KP:C:S. Not sure how fast it will burn up as a comet but it should go fairly quick and suit the need.

[Bonny]

If your matrix comp burns up too fast it will lend you with more of a star mine effect. You could just take a cup of dragon eggs and dump some slurry in to turn it solid but I think you might get the mine effect then. In the case you want that effect, a mine would be simpler. I would suggest trying just a straight KP replacement in a bp formula. So 75:15:10, KP:C:S. Not sure how fast it will burn up as a comet but it should go fairly quick and suit the need.

 

 

What I'm looking to do is have a few 1" comets falling from a very softly broken 3" shell...crackling nicely on the way down, but obviously finish long before they reach the ground.

[Mumbles]

I think you'd be disappointed with the KP comet. I have a feeling it will burn rather slow. It's really the pressure gradient in burst that makes it go. At atmospheric pressure, it will leave something to be desired. No matrix composition will burn so fast that it will leave you with anything that could be construed as a mine. You could use straight flash in a cored comet as the matrix, and you'd get a nice bright short tailed comet with some cracking out the back end and sides.

 

I have some compositions that should at home if you'd like. Do you have any preferences as for the effect. Color? Silver Streamer? Glitter? Charcoal? Dark?

[Miech]

C6 which has been milled airfloat and then is bound with a non-aquateous binder burns reasonable fast without being bright at all. I think that would make a nice matrix comet, although it is nitrate based. Charcoal streamers are not streaming when both airfloat and kept without water.

[Bonny]

I have some compositions that should at home if you'd like. Do you have any preferences as for the effect. Color? Silver Streamer? Glitter? Charcoal? Dark?

 

I think a silver streamer would be best, a silver tail with the crackle would make for a very cool effect I think. I would like the mix to be ~50% dragon eggs. A colour would be cool too. I know from past comets that the Velines for example, burn too slow.I was thinking of Bleser #14 Flitter, or maybe a Shimizu Silver Wave formula with an extra % or 2 dextrin to help hold it all together...

 

@ Miech, the only reason I want to avod nitrates is the possibilty of it leaching in and ruining my eggs. They have already been primed with 2 layers of Pax's "Veline style prime"...so maybe nitrate based comps might be OK??

[psyco_1322]

I know that with some small 3/8" pumped matrix stars containing dragon eggs and a bp matrix comp, I got a star mine-ish effect. The whole star burnt up and was at its max height by the time the dragon eggs kicked in. It gave a small cloud of crackling in the sky. I would think the same problem might happen in larger comets because of the delayed egg explosions. Although if it burnt long enough you should still get a stream of crackling effect.

[Mumbles]

I wasn't thinking on that small of a scale when I made my previous statement. When I hear comet, I automatically think at least 3/4" or 1" or larger. Something that small could potentially burn out too fast I suppose.

 

Here are some formulas that might suit your fancy.

 

Red:

Potassium perchlorate - 43

Strontium carbonate - 14

Saran 506 - 14

Magnalium 50/50, -200 mesh - 10.5

Red gum - 3.5

Charcoal - 7

Titanium, sponge +30 mesh - 7

 

Green

 

Potassium perchlorate - 43

Barium carbonate - 7

Barium Nitrate - 7

Saran 506 - 14

Magnalium 50/50, -200 mesh - 10.5

Red gum - 3.5

Charcoal - 7

Titanium, sponge +30 mesh - 7

 

Purple

 

Potassium perchlorate - 43

Strontium carbonate - 5

Copper Oxide - 9

Saran 506 - 14

Magnalium 50/50, -200 mesh - 10.5

Red gum - 3.5

Charcoal - 7

Titanium, sponge +30 mesh - 7

 

 

Fast burning Streamer

 

Potassium Perchlorate - 70

Potassium Benzoate - 30

Titanium or Ferrotitanium - 10-25 parts

 

 

Forli Silver Streamer:

1 kg kclo4

400 gr al atomized

300 gr al granules

200 gr al bright

100 gr red gum

100 gr arabic gum

 

 

John Reilly Silver Streamer:

 

Potassium Chlorate 15

Barium Nitrate 1-1/2

Red Gum 1-1/2

Charcoal Dust (A.F.) 1/2

"Bright" flake Alum. 4

Dark pyro flake Alum. 1

Dextrine 2

To be bound with water

 

Mike Swisher Silver Streamer

 

12 lbs. chlorate potash

2 lbs. saltpetre

1 lb. red gum

5 lbs. #808 or #810 (white) aluminum

2 lbs. #813 (flitters) aluminum

2 lbs. dextrine.

To be bound with wheat paste

 

You can probably sub in perchlorate for the above. I've heard going 70-30 Perc-Nitrate improves ignitability.

[psyco_1322]

I was thinking something along the lines of 3 or 4 inch comets when he posted, until he mentioned the 3" shells. Even then a comet 2.5" wide with a 1/2" or so core would leave about an 1" of burnable comp.

 

 

I am actually looking for a nitrate based streamer of some sort to use with all this bright Al I got from Cracker @ Underground gadgets. Most of my perc stash just went to whistle last night

[Bonny]

I was thinking something along the lines of 3 or 4 inch comets when he posted, until he mentioned the 3" shells. Even then a comet 2.5" wide with a 1/2" or so core would leave about an 1" of burnable comp.

 

For now I'm looking to add them to a shell, for a drooping,crackling effect. Maybe sometime in the future I'll start making some larger comets but not ATM, as I don't have any pumps that match my tube sizes.

[swervedriver]

I am actually looking for a nitrate based streamer of some sort to use with all this bright Al I got from Cracker @ Underground gadgets. Most of my perc stash just went to whistle last night

 

I used that same bright Al in some C6 +20% comets. Nice sparky tails, they burn really fast when the comp is ball milled before adding the Al. Just a thought.

[TheSidewinder]

Bumping this thread to bring it back to the front page and help those wanting to make comets.

[firetech]

I took some of those crackling micro-stars from those little plastic shells and made a matrix with it. Worked great. I used about 5% stars.

[Plasm7]

I'm pretty sure you have to put them in a mortar tube. I think the paper cup is just there to hold the lifting charge like on an aerial shell. But I haven't made these so IDK.

ya you definitely have to launch them out of a tube

[KruseMissile]

anyone know what size of comet i should attach to a 2" and 3" shell?