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My first aerial shells


Aspirina

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Hi all!

I are starting to work some aerial shells and would like to share with all. Tell me that I can do to improve my shells! :D

Ask any questions if you have doubts, I think no need to put the formulas of the stars...

 

 

http://oi68.tinypic.com/6nxuh5.jpg

 

https://www.youtube.com/watch?v=EvAWVni9TTY&feature=autoshare

https://www.youtube.com/watch?v=DqI1tNaNqNM&feature=autoshare

https://www.youtube.com/watch?v=kuUflFIzccg

greetings :)

Edited by Aspirina
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These are excellent shells!! You are well on your way, and will become more consistent with practice. I especially liked the last shell with blue. Beautiful! I only have 1 suggestion for you at this point: When you cut your stars, cut them all precisely the same size, that way they all have the same burn duration. It will make your breaks more symmetrical: https://youtu.be/T-doXknRwho?t=24s

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Not bad for first time. I'm always a sucker for blues. It's what I started on. Keep the stars as close as possible in size as Brad has said. Using a canule like you did in the latter of those is good, you want to do that. Keeping the stars against the wall and the burst in the middle. Mixing the inner petal stars with the burst is ok.. And keep up those blues!

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looking good ... what country are you living in ? I am in costa rica

 

memo

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Thanks all for the answers and thanks for the tips, I will apply the advice of the stars in my next shells. I have some questions:

- How much kclo4 flash powder should use for 2" and 3" shells? (burst charge) 70/30 ratio

- Which is the best way to gain height? more bp? or more paper? (to increase the diameter of the shell)


Memo, soy del norte de España (Catalunya) de un pueblo en la Costa Brava, es un gusto ver un castellanoparlante por aquí!



Thanks all for responding so quickly! ;)

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I was hoping that you lived in central America, still looking for other pyros here.

 

memo

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Aspirina, to keep it simple, add to your lift charge for more altitude. Make sure and document everything, and try to always make your lift and break bp exactly the same, that way once you figure out what percent of shell weight that you need, you can always use that amount and it will be the same every time. For example, if it takes 12% of shell weight in lift powder to reach altitude, and you milled your bp for 3 hours, do it that way every time and use the same ingredients from the same sources. Consistency is key here. Adding layers of paper to make shell fit tighter can also help, but it is much easier to find the % of lift that you need for your shells. You can use 10% of shell weight for lift powder as a starting point, but for most folks, the number will fall anywhere between 8% and 20%. There are many factors that affect this, even including the type of ball mill you have, and how you charge it. Later, as you progress, you may want to vary the altitude of different shells depending on the type of shell, and at that point it is important to have consistent powder. Like for example, with 4" shells... if I have a hard breaking single color peony, I like to break them right around 350ft. But with a slow burning comp (like Slow Gold), I like to break em at 450-500 ft to reduce the chance of fires on the ground. :P When you have consistent powder, you can literally pick your altitude. I noticed you had a low break with one of your shells. I know those are not fun! HAHA! So, go ahead and double the amount of lift you are using now, then slowly work your way back down. You can do this with small shells (2,3, and 4") no problem, you can't over-lift em. Keep up the good work!

Edited by braddsn
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Thank you very much for such a long answer! I will consider that as you said, I go testing different proportions and other charcoal for my lift powder. I should also write down all the tests I do, actually, is a good way to avoid making the same mistake twice.

 

greetings braddsn :D

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You know you've got to start stacking those, right? ;)

 

One issue with small shells is that they easily hang up in the mortar before reaching the bottom. To prevent this, use a dowel to make sure they're fully seated. I had a couple single break 1.75" go off low in the past. I attributed that to a failure to fully seat the shell. Then again, I've had one shell go low because my powder wasn't as powerful as I thought it was, and the mortar I fired it out of was short.

 

I now use longer-than-standard mortars and coarser 2FA lift because it tends to be easier on the mortars and the shells.

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Wiley, I think part of the problem with small shells seizing up in the tube is that if the fuse is on the side of the shell, it causes it to go partially sideways. I make mostly 1.75" balls (I know you'll say they're the wrong shape, but I like round breaks :P ) and the problem might be less prevalent in cylinders because they can't rotate much. To remedy shells getting stuck, I put a string loop on top, pasted under all the layers, so that I can put the fuse through it and lower the shell straight down the mortar. Most consumer reloadable ball shells have this string. The string is also a nice center marker for pasting around. I should add that I bottom-fuse all my shells.

Another cause for this problem might be the mortars. My pyro friend tells me that HDPE Excalibur mortars actually taper down from about 1.91" at the muzzle to around 1.75" at the base. This must be due to the manufacturing process. I believe that the mortars are injection molded and need to be tapered to facilitate release from the mold.

Of course, using a ramrod to push the shell down works, but I like to solve the roots of the problem so that I don't get an exploding mortar or just have a mild inconvenience.

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The second break on that shell was round, just not spherical :P. Cylinders break into a disk shape, which I and apparently many others find appealing, but that's also why it's common to see Maltese shells with three identical breaks of color. Sometimes the donut's edge will be oriented toward you, so the break looks like a line, but the next break may have turned 90 degrees and displays as a nice, round disk.

 

I don't use Excal mortars, so I can't comment there, but I do know that black powder fouling can make it hard to fit a shell that's already snug. With ball shells, I can't see the mortar exploding, unless a salute hangs up in the gun somehow. I had that mysteriously happen on a 1.75" plastic ball salute last July. Loaded it into a long Chinese paper gun and noticed that the shell wanted to bind going in, but I still managed to carefully lower it to the bottom without it snagging on the way down. When the lift fired, I heard a strange FWEEP, saw nothing come out of the mortar but smoke, and realized that the salute was still firmly planted at the bottom of the tube with its fuse alight. There wasn't much left of the mortar. I don't make ball salutes anymore.

Edited by Wiley
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I think the Excalibur mortars widen at the top after use. The lower portion is double thickness and don't expand.

I think I'll measure mine before use and stick with that for building.

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If they are in fact injection molded, then the core that forms the bore would have to have some draft to it or the part would never come out of the mold. Let us know what you find, Marine.

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Aspirina, something else to consider: You can use meal coated rice hulls (break charge) to lift your shells! I do this with all shells 5" and under. For me, the process of making coated rice hulls is easier and less messy than granulating bp, and sometimes it can even be a little more consistent. Start out using the same amount of coated hulls as you do granulated lift, and experiment. I am lifting shells this way and will never go back to granulated (except for 6" and 8" shells).

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I hope you are really happy after these, because these are great shells, especially for your first attempts.

 

Yes you had a low break, and some effects not light, but you can work on this, and I think you have a lot of things working well. Your spiking looks good and I loved the Tigertail with Blue. Two lovely stars mixed, in my opinion, in just the right ratio.

 

 

 

- How much kclo4 flash powder should use for 2" and 3" shells? (burst charge) 70/30 ratio

 

For a 2" shell I usually use between 0.5g and 2g. For a 3" shell 1g to 3g. It depends on what effect I'm after, and for other effects, you want no flash. With waterfall type effects I like to use only a few grams of BP.

 

With flash boosted shells, stars that light well in a BP only burst will not always still be reliable. In general my attitude with priming is that I prefer not to cut corners, and prime them better than what I think is the minimum. Sometimes if I have a very hard burst, (or just because I like the aesthetics of it) I coat all coloured stars, as well as strobes and other harder to light compositions with a hot prime (KClO4 based) and then a streamer based effect containing a good quantity of charcoal, such as Tigertail and other charcoal streamers, Brocade/Kamuro or some glitters, before finally priming with a black powder prime.

 

These streamers are star compositions that once ignited can be thrown as fast as is possible before the energy of the burst shatters them, and will always stay lit. While many coloured stars stat lit at respectable velocity, they can blow out at speeds that shells are able to throw them. When a shell is this powerful, the initial streamer effect burns for the first few moments or seconds so the stars can slow down enough for the other effect to be reliable, and of course looks great.

 

Your card disks look like they are made of corrugated card, from an ordinary cardboard box. While I should confess to having used these in 2" and even 3" canisters, it is not a very good material because it can compress so much, weakening the shell casing. Due to the large force placed on the base of canister shells solid card disks should be used, especially when you make larger ones.

 

If solid card of suitable thickness is not easily available for you, stacking thinner card with some PVA between each sheet is a relatively easy way to get solid can shell end disks.

 

 

- Which is the best way to gain height? more bp? or more paper? (to increase the diameter of the shell)

 

There are many ways to improve how BP is used to lift a shell, including making better black powder, using a finer granulation, using more BP, improving the confinement of the BP, improving the mortar, and having the shell a bit larger if it is loose in the tube.

 

Unless I missed it, I think you have not said what your methods are, and so it is hard to give the most suitable advice.

 

Similarly do you know of anything different with how you lifted the shell with a low break?

 

Other than what has already been said, from personal experience I know that with BP that is not that great, but has been milled a bit and has ok charcoal, you can get Black powder that will lift a shell reliably if, say, 20g was in a firm ball in a plastic bag under a 3" shell with two layers of pasted paper, but if it was in a loose bag simply under the shell, without those two layers of paper, the shells would be quite inconsistent and many would break very low.

 

I think if you make sure your shells are seated in dry mortars and make nicely milled BP with a good charcoal, you should be fine :)

Edited by Seymour
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Hi all!

 

 

You know you've got to start stacking those, right? ;)

Ofcourse, I inspired in your comment Wiley, and I will discuss what went wrong :blink:

 

 

 

Aspirina, something else to consider: You can use meal coated rice hulls (break charge) to lift your shells! I do this with all shells 5" and under. For me, the process of making coated rice hulls is easier and less messy than granulating bp, and sometimes it can even be a little more consistent. Start out using the same amount of coated hulls as you do granulated lift, and experiment. I am lifting shells this way and will never go back to granulated (except for 6" and 8" shells).

the idea of rice hulls sounds good! How much should I wear? for example to raise 50g? Is the same 10%-15% of the total weight?

 

thanks for all the councils Seymour, been very constructive! No where to get a thicker cardboard, I realized that I use not work very well. My bp is made with pine charcoal, but, for lift shells I use Poplar charcoal this works better than pine, so fast bp. My ball mill is a chicago rock tumbler 3 lb (my first ball mill) I use ceramic balls for milling and 1cm screen for granulate it with alcohol/wather. Works very well!

I have tested some of your tips in a new shells, and I will share advances :P

 

thanks for the time spent on the answers!

 

 

 

Greetings :)

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"No where to get a thicker cardboard, I realized that I use not work very well."

-----------------

That's no excuse if you have paper and paste! You can make your own from 'scratch', or make thinner material thicker at your whim. All it takes is a bit of work and some drying time.

 

Lloyd

Edited by lloyd
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Hard bound book covers and 3-ring binder covers is a good resource for heavy disc materials.

I see these on CraigsList every so often in the free section and will pick them up if close by.

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Aspirina, yes use the same amount of coated rice hulls as you would normal granulated bp. For example, if it takes 15g of granulated bp to lift a 100g shell, use 15g of hulls to lift the same shell. My hulls are 7:1 (7bp:1hulls)

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Coated rice hulls work, but you are building cylinder shells, after all. The traditional thing to use is granulated black powder, which, if you've been using it, I would suggest that you keep doing so. If, for whatever reason, you decide that you want to use the hulls to lift these, just make sure that hulls never get inside the shell too. To quote Mike Swisher, "Mixing Oriental practice with Italian is like putting soy sauce on spaghetti - the total is less than the sum of its parts, and ingredients that are each good on their own are combined to make a dish no one would care to eat."

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Aspirina, yes use the same amount of coated rice hulls as you would normal granulated bp. For example, if it takes 15g of granulated bp to lift a 100g shell, use 15g of hulls to lift the same shell. My hulls are 7:1 (7bp:1hulls)

 

 

Coated rice hulls work, but you are building cylinder shells, after all. The traditional thing to use is granulated black powder, which, if you've been using it, I would suggest that you keep doing so. If, for whatever reason, you decide that you want to use the hulls to lift these, just make sure that hulls never get inside the shell too. To quote Mike Swisher, "Mixing Oriental practice with Italian is like putting soy sauce on spaghetti - the total is less than the sum of its parts, and ingredients that are each good on their own are combined to make a dish no one would care to eat."

 

hahahahaha good reference wiley! anyway I will try, curiosity piqued me...

inspired by your multi break shell, I try to make one of these. Something went wrong, I think it was the carton board of the bottom (be warned me) the explosion broke the first shell... at least the second exploded in the sky. the video shows d1 glitter stars shoot out the mortar, then blast the second shell, but do not see the

blue stars... The other shell is a TT palm (This time I put 2g fp, to hear a good boom!) I hope you enjoy it :)

 

Here's the video, sorry I do not have a decent video of the failure ...

https://www.youtube.com/watch?v=YJJiOa8hiaU&feature=autoshare

 

http://oi67.tinypic.com/1zlx9wn.jpg

 

http://oi67.tinypic.com/qnofb4.jpg

 

A greeting! Un saludo! Una salutació! :D

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Your lift is taking up a lot of space. Making it more compact might help your lift. Too much space can cause your lift to lose efficiency. The lift is basically the size of one break, which seems really odd.

 

Secondly, I'm not surprised your double break flower potted. You missed a couple of key points. I'd suggest taking a look at Pyrotechnica XI. You have to spike the breaks separately. If you don't, when the first shell breaks, the second shell will have basically no reinforcement since some to all of the string is torn away. In the traditional italian method, you spike the first shell with verticals only, then place the second shell on top. Then you spike the whole thing together with verticals. Spiral the string down to the bottom and spike both shells with horizontal spiking at once. At the joint between the two shells, you lay closely spiked horizontals, essentially making a solid band. Continue up and finish off the top shell. This is done to reinforce the joint between the shells, which is often a weak point. It's hard to tell what caused your shell to fail, but I suspect making these modifications to your process will prevent it in the future.

 

You're off to a great start. My first shells certainly didn't look this good.

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