25 replies to this topic

[BlackMesa]

Where do you guys get your perc from? - having problems locating any otherr than on inoxia but i dontt fancy doing the age verification paperwork just yet, alot of bother.

Not having much success with my shells breaking - im using meal powder to break in my small shells but it just seems to rip a small hole in the shell - normaly near where the fuse goes in and then all the sparks and hot air fly out of that like a rocket? this is why i was considering getting some perc to make some kp/al perc flash for breaking?

perhaps my homemade fuse makes a weakpoint in the shell, its good fuse but about 2-3mm thick.

[pyromaniac303]

Try granulating your meal to pulverone, and pasting more layers on the shell. Can you give me any more details about the shell casing, stars, and your meal powder? Maybe when you close the shell you compact the meal powder forcing it to burn from one end to the other.

[BlackMesa]

Try granulating your meal to pulverone, and pasting more layers on the shell. Can you give me any more details about the shell casing, stars, and your meal powder? Maybe when you close the shell you compact the meal powder forcing it to burn from one end to the other.

Since my shells are quite unsuccessfull currently im just exploding(well almost) on the ground. The meal shouldnt be too compresed as i prepare it by placing it in the centre of a piece of kitchen roll, putting my fuse in the middle and folding the edges up - effectively making a small parcel of BP with a long fuse coming out of it, this is then placed in the middle of the shell with the fuse coming out of a small hole. my shells are made by papier mache-ing around 2 halves of a tennis ball with several layers, when this is dry i then take these halves off the tennis ball, put my blackpowder parcel in the center of one half and tape this into place with a bit of masking tape. Then with the fuse sticking out of one with (through a small notch cut in the edge of one side of the shell). The other half then put on top of it (like an easter egg) i tape around this with makingtape then add more layers of paper and glue. It is normaly along this join point these slits in the shell appear when its ("bursting"). Sparks spew out from the join point along the "Equator" but they dnt completely sever the shell in half just make gaps to release the air.

Even with more layers of paper on the shell i dont see how i can avoid having the hole for the fuse - though it is small surely the hot air will just be released out of this instead of the shell bursting if i make it too tough

Sorry if non of that made any sense itsa bit of a mouthfull!

[dr thrust]

getting a good break on a shell is definitely a fine "art" meal in a parcel wont cut it you'll need a fast bp using a willow charcoal on a carrier like rice hulls, rice krispies. your "fuse" should be in the form of a spolette which is a good method of delivering the flame to the center of the burst charge helping to give a spherical break, also good pasteing makes all the difference, many people find it hard to paste a shell well and opt for plastic, heres a good link to making shells read read read

Edited by chris m, 08 August 2008 - 11:38 PM.

[MDH]

Again, looking towards consumer fireworks, I couldn't necessarily say this is true. Bombette canisters, for instance, are often a way to get breaks and are really all that is necessary if you have go getter inserts or a lot of flying fish and small stars.

However, more refined techniques such as those you'll be reading about are definitely what you want if you really desire to have very spherical breaks, or palms and other shape reliant effects.

[dr thrust]

hmm intriguing! may one inquire what a bombette canister is?, construction , charge,ect, always eager to learn new things

[pyrotrev]

I guess he means the cylindrical inserts that are usual for bombette effects in cakes and candles. With a BP burst it will give some kind of a bouquet burst (pops one end out), if you want anything resembling a spherical break it's going to have to be flash, and even then it'll never be as good as a round shell.

[Mumbles]

Don't be so sure about that. It usually just takes some dialing in based on the strength of your BP. It's a balancing act between spiking and pasting with how strong your burst is. It might take a few testers, but I assure you it's possible to do.

[StarScream]

Thanks for the information guys, I'll make some shells this weekend and hopefully fire them the next. I'll just use straight granulated KP in them so I'll get more of it inside the shell, the shells will be 3". Hopefully they will turn out OK, better than straight BP anyway.

Pretty Green Flames:
I'm curious to know how the granulated KP worked out for you? I've recently been wondering if KP could be used granulated like H3, in small shells, rather than rolling it onto a carrier like rice hulls.

[Pretty green flames]

Pretty Green Flames:
I'm curious to know how the granulated KP worked out for you? I've recently been wondering if KP could be used granulated like H3, in small shells, rather than rolling it onto a carrier like rice hulls.

Worked OK I guess, though you can get quite as good breaks with straight BP, and besides, BP is cheaper than KP. Overall, I wasn't all that impressed with KP in my canister shells.


This was one of the KP broken ones, bow tie break, most likey due to my sloppy spiking job. The BP broken ones performed more or less in the same way.

[StarScream]

Worked OK I guess, though you can get quite as good breaks with straight BP, and besides, BP is cheaper than KP. Overall, I wasn't all that impressed with KP in my canister shells.


This was one of the KP broken ones, bow tie break, most likey due to my sloppy spiking job. The BP broken ones performed more or less in the same way.

The problem with KP is it needs high pressure to burn fast and give a good burst. Pasting more layers might help, as well as a bit of whistle mix to boost the KP.