Aerial Shells

[qwezxc12]

Some good efforts, there...even the flower-pot at 3:10 was pretty. I liked the series at 5:30 - 5:45 or so...nice breaks. What was the deal on the salute at 6:40? I would have run for cover if I knew that was heading for me!

 

How many builders contributed? Wish I had something like that to attend in my area...

[justanotherpyro]

Very nice crossete shell at the end. it seemed like they were timed just a bit short but it was a very well made shell IMO.

[InRainbows]

Who made that shell around 5:38? That looks almost like tourbillions, I think that's called a farfalle shell? Anybody want to shed some knowledge and say exactly what and how a farfalle shell is made? It looks almost like a shell like a bunch of comets, it's just that, they spin, looking sort of like a serpent. Also, that crossette shell around the end was fantastic.

[qwezxc12]

I realized that four months passing without lighting anything substantial is more than any pyro can stand, so I've put some time in the shop over the last week:

http://www.apcforum.net/files/Apr08shells.jpg

6in Win20, 6in Ruby Red, 4in Willow, 4in mixed Blue flash-core and Ti stars, and a 4in Ti streamer. With luck, I'll get to shoot these off for my stepfather's B-day later this week. I hope to add some 3" Chrys8 flash-core shells, and maybe a few mines as well.

[ST1DinOH]

I realized that four months passing without lighting anything substantial is more than any pyro can stand, so I've put some time in the shop over the last week:

http://www.apcforum.net/files/Apr08shells.jpg

6in Win20, 6in Ruby Red, 4in Willow, 4in mixed Blue flash-core and Ti stars, and a 4in Ti streamer. With luck, I'll get to shoot these off for my stepfather's B-day later this week. I hope to add some 3" Chrys8 flash-core shells, and maybe a few mines as well.

i must say, you make some amazing looking shells...

 

looking forward to watching the vids, especially on the 6's.

 

speaking of that...is there a rhyme or reason to the lift placement on the larger shells?

 

in otherwords will a conical shaped lift cup differ from a flat bottom'ed cup...

 

what about lift bags...

 

is it more bennificial to spread the lift out evenly or to have it balled up?

 

i would assume with the slower burning large grained BP's the more spread out the lift is the faster it would all defligrate.

 

does this matter at all in a 6 or is that sort of thing only a concern when you get into much larger shells?

[Richtee]

Seems I can't post a new topic, but as regards spiking... Why do I not hear/read more of the fiberglass re-inforced packing/strapping tape?

 

I'm pretty new to shell construction and have done maybe 10 2" can or italian styles, but have had pretty good results with the tape.

 

Any one have info on this aspect of shellbuilding I am most likely missing?

[justanotherpyro]

Many of us ( self included) us gummed fiberglass reinforced tape for shells. Im not 100% sure but I believe that qwezxc12's shells in the picture are pasted this way. The reason why it isn't discussed a whole lot is because it is all pasting, just different methods. Either way, its just personal preference in saving time, or perfecting a finished look. The clear fiberglass strapping tape is good as well, but again its just a faster way of pasting shells that may or may not affect performance. There are many many variables.

 

There was a picture somewhere in this thread a while back that showed a 4" shell being pasted with 4" fiberglass strapping tape which may help you out.

[Richtee]

Thanks much... I just joined here and have not read a ton yet just did a search on 'spiking". Look forward to learning the art.

[Mumbles]

Generally the fiberglass tape is used with plastic shells. I personally find it sticks better than paper. I've seen a few paper canister shells spiked with it, and most have flower potted. I just don't think it offers the same characteristics as string and pasted paper.

 

However I have heard from several manufacturers that they used the tape in some tests and achieved good results with trial and error. Most of their tests were of course with plastic ball shells, but a few canisters. They said that the cost and time saved were not worth it enough for it to be practical. With the mass shot 3" and 4" shells it might work out alright though as the performance is not as critical, and the huge numbers of them may make it impractical to spike with string and paste.

[psyco_1322]

I bought some fiberglass reinforced gummed craft, and im using it to paste some 3" ball shells. Using a 3 strip method of 1/2" strips. So far I only put on 3 revolutions but its really 6 layers. Should I use more, less, or shoot it? Just looking for suggestions on pasting with reinforced gummed paper.

[Richtee]

I bought some fiberglass reinforced gummed craft, and im using it to paste some 3" ball shells. Using a 3 strip method of 1/2" strips. So far I only put on 3 revolutions but its really 6 layers. Should I use more, less, or shoot it? Just looking for suggestions on pasting with reinforced gummed paper.

The shells I did had 3 wraps on the bottom shot and 1 wrap on the pretty can. Probably did not need 3 for the bottom as the comp was something that is not to be discussed here, but I had a good break on the pretty stuff. No way to measure the spread, but I have seen less out of 3" commercial shells, on occasion.

 

Shoot it and observe would be my course. But I'm a newbie, and I like the pretty colors :{)

[Mumbles]

It's hard to say really. I'd shoot it as is. With normal kraft, you really only need 9 layers as it is. You can't tell if you need more or less without shooting it. All my gummed tape experience is with larger shells, and unreinforced tape.

[justanotherpyro]

Thats how I do it. 3 overlapping layers of gummed reinforced tap for a total of 6 layers and I have had good results. Another thing to consider that could go horribly wrong is how well it will fit into the mortar. I have pasted 4inch shells before that were way to snug in the mortar for my liking which I found out after pasting them. It was only 2 layers which was irritating/surprising.

[ST1DinOH]

Thats how I do it. 3 overlapping layers of gummed reinforced tap for a total of 6 layers and I have had good results. Another thing to consider that could go horribly wrong is how well it will fit into the mortar. I have pasted 4inch shells before that were way to snug in the mortar for my liking which I found out after pasting them. It was only 2 layers which was irritating/surprising.

this is going to be my problem i fear...

 

recently i purchased some plastic 6 inch shell hemi's and a 6 inch HDPE gun. when i got both items together and checked the clearence on the bare empty shell...there wasn't a whole lot of room for error.

 

i'm worried that anything more than one or two wraps with the fiber tape and it's not going to want to drop in the gun freely...

 

with a 6 inch shell i sure don't want to be ramming it down the gun...

 

for about 10 reasons.

 

i may just scrap the idea of a 6 inch shell and use the tube for a big ass creamora or star mine.

[justanotherpyro]

i may just scrap the idea of a 6 inch shell and use the tube for a big ass creamora or star mine.

Well if you already dropped the money to do it, then you might as well make them. Just paste one layer, test the fit, paste another test and so on. As you know, many of us here do 6" shells and most likely have used the same hemis and same size pipe that you have purchased.

 

Making the shell too big should be something to be aware of, not something that will prevent you from doing it

[ST1DinOH]

i may just scrap the idea of a 6 inch shell and use the tube for a big ass creamora or star mine.

Well if you already dropped the money to do it, then you might as well make them. Just paste one layer, test the fit, paste another test and so on. As you know, many of us here do 6" shells and most likely have used the same hemis and same size pipe that you have purchased.

 

Making the shell too big should be something to be aware of, not something that will prevent you from doing it

well here's where it gets confusing...

 

i was going to ask the question "does anyone else have this problem"...but i wasn't sure how "universal" the parts are.

 

in other words i'mnot sure if all the plastic hemi's out there are the same OD or if all HDPE guns have the same ID or if somehow i got the bad combo of an abnormaly large shell and an abnormaly small ID HDPE.

 

then again if all the shells and HDPE guns are universal that brings up a different question...

 

do some shell sizes have more play in thier respective HDPE guns?

 

in other words is the 6 inch plastic hemi + HDPE combo a rare problematic one? i've never seen a bare empty shell hemi fit so damn tight.

 

anyway i hope you get what i'm asking...i think there is more than one flavor of plastic shell out there...some larger than others.

 

there may also be more than one ID size of HDPE depending on where it's coming from.

 

but the later is a much less likely scenario.

 

i need more info on building a 6 inch shell before i feel comfortable building one, let alone sending one up. i'm also running out of time with all the projects i have on the list between now and the 4th. hence the retreat to creamora or starmine.

 

the big bonus there is i can fire a cremora or mine much closer to my audience than that big arse 6 inch shell...

 

nothing scares the hell out of a crowd like a 6 inch creamora blowing close enough to feel the heat.

 

aka "the brown note"

[justanotherpyro]

I understand what you are saying. The 4" HDPE pipe ID is a bit wider than 4" ABS pipe. As far as the hemispheres, in my experience, they have always been the same with the exception being that paper casings are bit smaller than the plastic ones. Here are some pics of a 6 inch hemi's clearance in my 6" mortar. This mortar has a beveled edge which can be deceiving so look closely. The clearance of the hemi pushed to one side of the mortar was .7cm so the actual clearance of the shell perfectly centered is .35cm which is a very short distance it seems but it works.

 

http://i42.photobucket.com/albums/e301/justanotherpyro/IMG_0569.jpg

http://i42.photobucket.com/albums/e301/justanotherpyro/IMG_0566.jpg

 

 

MODERATOR EDIT:

I fixed the formatting. For everyone's future reference, always put a carriage return before starting the IMG tags.

Edited April 3, 2008 by TheSidewinder

[ST1DinOH]

I understand what you are saying. The 4" HDPE pipe ID is a bit wider than 4" ABS pipe. As far as the hemispheres, in my experience, they have always been the same with the exception being that paper casings are bit smaller than the plastic ones. Here are some pics of a 6 inch hemi's clearance in my 6" mortar. This mortar has a beveled edge which can be deceiving so look closely. The clearance of the hemi pushed to one side of the mortar was .7cm so the actual clearance of the shell perfectly centered is .35cm which is a very short distance it seems but it works.http://i42.photobucket.com/albums/e301/justanotherpyro/IMG_0569.jpg[/iM G]

http://i42.photobucket.com/albums/e301/justanotherpyro/IMG_0566.jpg[/iM G]

not sure if you tried to post two images...but the second one isn't working...

 

this is the exact problem i'm having with my combo of plastic shell and gun. first time i've seen this happening on any other sizes. the 1.75's, 2's, and 3's all seem to have more wiggle room than this 6 inch combo i have.

 

meh

 

i'll make it work with 2 layers and just ensure it's smooth and there's no "bubbles" in the tape.

 

i'd just hate to spend the time and money building a 6 and see it quief in the air with a shitty break due to lack of confinement.

 

some of the nice shells i see you guys making are always described as having multiple layers of craft pastings...

 

now i know fiber tabe is stronger than pasted craft but i wouldn't think i'd be that much stronger.

 

one thing i will say though is the plastic 6 inch hemis are substantialy thicker than the 3's or 1.75's i'm used to. i was suprised at how durable they are. much more so than the smaller shells. so i'd venture to guess that once properly bonded it starts out stronger than smaller ones.

 

so they must not need much additional tape to give decient results.

 

the bonding seam on these hemi's are much bigger than i was expecting.

 

on a three i could barely open the hemi's up about 1/16 of an inch (used my thumbnail and it was perfect), but on the 6's i have a good 1/4 inch of play to get a very tight bond on that seam.

 

basicly i was impressed with the hemi's quality. i got them from cannonfuse.

 

i can't wait to try them out but i sure don't want to jump into 6's untill i've sent up at least a few dozen more 3's.

 

EDIT: nevermind about the img's they both work just fine now.

 

thanks again thats just about the same clearance i have on mine.

[qwezxc12]

FWIW, I have only Kastner HDPE mortars and they seem pretty true to ID. They do get smaller when it's really cold out, though.

 

I've used plastic hemi's from both Pyrocreations and Cannonfuse...the 3's are white, and the 4's and 6's were black. They appeared to be from the same mfg. and were fairly tight if pasted.

 

Last summer I bought a full case each (250 and 100) of 4's and 6's from Pyrocasings. These are made a bit better from a fit/finish perspective, have a deeper lip for mating the two halves and (most importantly) are slightly smaller allowing gummed paper tape pasting without needing to jam the shell into the mortar.

 

My current batch is actually pasted with 5 overlapping layers of 30lb. non re-enforced tape as opposed to the three layers of 60lb. re-enforced tape I used before...a little experiment to see if I can get away with the plain tape. I want to go this route because the 30 lb. tape is available in 1" and 1.5" widths and I won't have to slit 3" rolls of the heavier tape down any more.

 

On a down note, I can't fire those shells off this week as planned, so they will sit until I get back from Dubai on the 12th One a positive note,,,I'm going to Dubai

[Bayarea510]

basicly i was impressed with the hemi's quality. i got them from cannonfuse.

dang man buying from others! how rude! The casings both Steve (pyrocreations) and tony (asshole eyes cannonofuse ) do in fact come from the same company. There are only 2 other companys out there that I know of that makes plastic hemi's. The ones from the company that the two above companys buy from seem to be a little tighter then the company I buy from. When making 6's at WWB we didnt seem to have any issues with tightness of the shells in the guns, and this was with atleast 2-3 layers of strap tape.

 

Now as far as how much you need to make it "look good" in the sky. I have shown many of people how only 1 layer will work just fine with a "hard" break (aka 50-60 grams of FP). I know alot of people are going to be like WTF are you saying, are you out of your mind? As long as your stars are WELL primed they will light! At WWB I had a group of people that were looking at me crazy at the event until the tried my way of doing it! here is a little video just so you can see how hard these shells break. http://www.pyrotubes.com/images/WWB19-RobW-SatShells.mpg

 

 

Bay

[qwezxc12]

Now as far as how much you need to make it "look good" in the sky. I have shown many of people how only 1 layer will work just fine with a "hard" break (aka 50-60 grams of FP). I know alot of people are going to be like WTF are you saying, are you out of your mind? As long as your stars are WELL primed they will light! At WWB I had a group of people that were looking at me crazy at the event until the tried my way of doing it! here is a little video just so you can see how hard these shells break.

Bay,

 

Did you post those over at Passfire? I saw them somewhere before and always meant to ask the "speed" of the FP you use. I currently use 5g in my 4in, and 20g in my 6in shells made from either -325 coated flake or -450 flake, for a relatively "slow" FP...shooting for more of a stout shove as opposed to a hammer blow upside the head. 50g in a 6in? I would think that qty of any traditional 70:30 mix would totally nuke the stars into dust.

 

So, if you don't mid, what type of Al are you using? Thanks.

[FrankRizzo]

An ounce or more of FP also adds a bit of $$ to the shell.

[Bayarea510]

Bay,

 

Did you post those over at Passfire? I saw them somewhere before and always meant to ask the "speed" of the FP you use. I currently use 5g in my 4in, and 20g in my 6in shells made from either -325 coated flake or -450 flake, for a relatively "slow" FP...shooting for more of a stout shove as opposed to a hammer blow upside the head. 50g in a 6in? I would think that qty of any traditional 70:30 mix would totally nuke the stars into dust.

 

So, if you don't mid, what type of Al are you using? Thanks.

no that was my buddy that posted those on passfire. I am the "guy" he is thanking in the video lol As far as what AL im using, its the standard eckart 5413 SUPER. most people say the same thing you are, wow i would think it blows them baby to dust but it doesnt. as you can see we get great speard. I have been told before our 8's look like 12's

 

now when your shells break do the look more "clumped" together or do you get good spread using the slow FP? Now I have noticed that when using paper shells we dont blow them as hard as the plastics (duh huh?) and we still get a good spread...

 

 

Bay

[Bayarea510]

An ounce or more of FP also adds a bit of $$ to the shell.

frank seeing FP only cost me about 4.70 a lb and less then .30 cents per Oz it doesnt bother me to much

 

 

Bay

[qwezxc12]

now when your shells break do the look more "clumped" together or do you get good spread using the slow FP?

Bay,

 

Thanks for the details on your shells. Best example I have of my construction is this one: 6in C6 to Yellow

It's plastic...details are in the competition forum.

 

I notice that I'm timing longer and shooting my 6's a lot higher. I use the following as a guide:

Time Fuse Delay Times

Shell Size...Delay Time

(in.)...........(sec.)

3.................3

4.................3.5

5.................4

6.................5

8.................6

 

As an example, the 6in Blue and Silver from your vid only took 117 frames (3.9 sec) from lift to burst, whereas mine took 169 frames ( 5.6 sec).

 

That would change the apparent spread and speed of the break, making my higher shell look smaller and slower. I may try a "less lift and less time" experiment to make mine break lower and see the difference.