Festival Ball Tutorial?

[pyroguy1960]

Thinking of building some festival ball shells, I have some 1.75 inch plastic shells, but have no idea how to fuse it. I figure I'll use green visco for time fuse but not sure of the length to use, also don't know how much lift to use. I have some commercial 2F and some cannon grade BP. Anyone advice or links to articles?

[Mumbles]

If you're on Passfire, search for some of Eugene Yurek's posts. He outlines his method in detail, and supposedly get so good of results he has no need to make any other size. With these small shells, I'd ere on the side of caution. Time to around 1.5 to 2 seconds, and start with 5g of 2fg lift. You can always back the lift off later. You wont fail with that much lift, or that short of timing. The timing would be around .5" to 3/4" depending on how fast your fuse burns.

 

The other thing I've heard is to paste the shell in with a few layers of paper, even though it's plastic. It is reported to really help the symmetry.

[pyroguy1960]

sounds good, I'll try it out tomorrow....have some old mouse turd rolled stars that were way to small to use in other shells...

 

 

[Cookieman]

If I'm not mistaken,Turbopyro from skylighter also has a tutorial on Festival ball shells.

[pyroguy1960]

I tried to find a direct download link for that PDF a few times and couldn't seem to dig one up....

 

 

[Peret]

There is a section in Turbo Pyro, yes. It's enough to give you a good start. I started a thread over on Pyroguide Forum also.

 

I can summarize the Turbo Pyro instructions in a few lines, with some of my own practical comments added. Note: Turbo Pyro recommends using commercial Goex for lift and burst because they don't expect a beginner can make decent BP. I'm no beginner but I still use commercial Goex for lift, because it's always consistent and reliable, and one $20 can lifts over 100 small shells.

 

Fuse your hemis with 1.5 inches or more of 1/8 inch Visco with a 1 inch length rolled in masking tape - takes about 1.5 inches of 1 inch tape - to be quite a tight fit in the hole. Put hot melt glue on the masking tape section and quickly twist the fuse into the shell from the inside until the taped length shows about 1/8 inch. Run a bead of hot melt around the outside to seal it, staying on the masking tape. The inside end of the fuse should be at least 1/4 inch untaped and come somewhere near the center of the sphere. There should be over 1/4 inch untaped on the outside end.

 

Line the two halves of the hemis with stars - you'll have to support them somehow, like on rings cut from a toilet roll tube. Turbo Pyro suggests Chrysanthemum 8, which it also tells you how to make. The stars mustn't project above the edges or the shell won't close. Fill both halves to the top with 2FG commercial Goex burst charge. Put a piece of thin card over the top half to hold it together and quickly invert it onto the lower half, then while squeezing the halves together slide out the cardboard. Expect some spillage, do it over a sheet of paper. Tap, twist and push the hemis until they lock together. This can be quite difficult until you get some practice. You may have to empty it out and start again - several times! Note, keep the equator horizontal all the time, or it WILL spill.

 

When the hemis are mated, ease them apart just a little bit with a knife so that you can put glue in the joint. Use MEK, clear PVC cement or Xylene, and a toothpick. This is messy. Get plenty of glue in the joint all the way round, and rotate the top half on the bottom to spread it - it stiffens up quickly. Don't slip, as if the shell opens when there's glue on it the powder will get in the glue and you won't be able to close it again. Press the two halves hard together and set aside to dry - VERY IMPORTANT - the shell has no strength until it dries. This takes hours, not minutes. Overnight is good.

 

--- later ---

 

Tape the shell with 8 to 12 pieces of 1/2 inch (or 2 inch torn into 4 strips) fiberglass strapping tape, starting one side of the fuse and going round to the other. Don't damage the fuse. I personally think this is a waste of time if the shell is properly glued, but that's what Turbo Pyro says. Rub the tape down hard and flat. I say again, don't damage the fuse. It's a good idea to weigh the shell at this stage - it should be in the region of 33 to 36 grams. Make the leader and lift. Cut a suitable length of green visco a few inches longer than the mortar. Bend a 1/2 inch hook in the end. Weigh out 3.5 grams of Goex 2FG, this is about a slightly heaped half teaspoon. Put the Goex in a corner of a baggie, twist the corner into a tight little pointed bag and cut it off about an inch up the twist. Insert the hooked end of fuse in the powder, gather and twist the baggie tightly round the Visco and tape it securely with masking tape.

 

Cut the shell fuse on a long diagonal to expose the powder core. Turbo doesn't say to prime it, and it doesn't seem to be necessary. Push the lift bag hard against the fuse, extra points if you thought of pushing it against the long cut side. Secure with tape and wrap the lift bag completely with masking tape to protect it. Take it out and fire it.

 

Photo: plastic 1,75 inch festival ball, Bleser blond streamer stars, BP on hulls break. Weight 34g, used 3.5g Goex 3FG lift, fuse delay 2 seconds, burst height about 400 feet.

[Peret]

I should also mention that it's a good idea to test your fuses, in case the burn time is radically different from what you expect. Tape them down to test or they'll fly away. After I settled on a particular batch I marked it for fuse use and don't use it for anything else. That way my shells all come out consistent. Leaving 1/4 inch inside above the masking tape helps consistency, as if you cut it off flush it spits early; also the side spit from that last 1/4 inch makes for reliable ignition. I tried priming the outside fuse with NC lacquer and BP but the acetone dissolves the fuse coating and it disintegrates, giving me a couple of duds. I haven't had any failures (yet) with unprimed.

[pyroguy1960]

Thanks to all for the advice on this, they worked out well, perfectly timed and lifted. Kinda suck though when you're used to seeing larger shells in action....feels like going back to consumer fireworks.

[Peret]

Thanks to all for the advice on this, they worked out well, perfectly timed and lifted. Kinda suck though when you're used to seeing larger shells in action....feels like going back to consumer fireworks.

True. The small capacity of 1.75 inch is a bit of a limitation, but try using smaller stars so you can get more of them in the casing. You will never get a full chrysanthemum sphere, though, as there just isn't room for enough stars. On the other hand, they can be pretty good. I've been highly impressed with some of the tiny Chinese shells I saw this year and wonder how they do it - I'm planning to dissect some when I have time and see if I can work it out.

 

The next step up to 3 inch makes a dramatic difference, as the internal volume is five times greater (ratio of diameters, cubed). Five times the weight, five times the lift at least - you'll probably want an extra second on the time fuse to get them a bit higher. But perfect the small ones first.

[snowycole]

True. The small capacity of 1.75 inch is a bit of a limitation, but try using smaller stars so you can get more of them in the casing. You will never get a full chrysanthemum sphere, though, as there just isn't room for enough stars. On the other hand, they can be pretty good. I've been highly impressed with some of the tiny Chinese shells I saw this year and wonder how they do it - I'm planning to dissect some when I have time and see if I can work it out.

 

The next step up to 3 inch makes a dramatic difference, as the internal volume is five times greater (ratio of diameters, cubed). Five times the weight, five times the lift at least - you'll probably want an extra second on the time fuse to get them a bit higher. But perfect the small ones first.

 

 

I think that they fill the hemis to the top with stars, then pour the break over the stars until all the cracks are filled.

[Mumbles]

That's generally called poka filling, and is common. It makes the break look fuller, but they are generally smaller. If you notice, some of the best shells on the market are all cylinders.

 

The hard and big breaking cylinders are made a special way. The tube is pretty thick, 1/8" or so off hand I think. A thick clay plug is rammed in the bottom of the tube. A hole is then drilled/formed to accept the time fuse. The shell is filled with stars, granular BP and flash or whistle mix. Everything is compressed down together, and another clay plug is pressed on top. I heard something about them being wrapped with more paper. If you open or cut one up, they are pretty much a solid plug of comp.

[Fly]

Mumbles whats the plug on the top for????

 

Fly

[pyrokid]

Mumbles whats the plug on the top for????

 

Fly

 

I am pretty sure it is so the shell can build up pressure before breaking, thus giving a larger break.

 

Some of those plugs come back down still intact, those are no fun.

Edited September 4, 2010 by pyrokid

[Mumbles]

It's so the shell has equal confinement on top and bottom so that it doesn't just hose break. With enough flash or whistle in those shells, nothing comes down intact. A gentleman I know who has been working on recreating these I believe uses 1tsp of a fairly sensitive flash powder, which is a gram or two.

[snowycole]

Ah okay I get it. So would you reccomend skipping 1.5" ball shells and going straight to cylinders of the same size?

[Zarwid]

Hello folks,

 

I hope that my resurrection of this thread will be helpful to you guys.

 

When I just started making out 1 inch and 1.75 inch shells, I felt like I was in the dark. There is soooo little information about Festival Ball sizes and smaller out there, that it required a bit of experimentation with them until I was in the vicinity of doing it right. But what really cinched it for me was this particular PDF. ( It is the top result on the page. You'll need Google Docs and to click on 'Quick View' to read the damn thing, otherwise there seems to be something wrong with the original PDF)

 

I was initially skeptical of the what seemed like a high amount of break charge required (1/2 a TSP of equivalent Goex FFg powder in each hemisphere), but it seems that the smaller aerial shells need a harder break in order to have good form and symmetry. I use a little bit more lift than they mentioned here, 5 grams of Goex FFg to lift around the shell that weighs ~28 grams once pasted three times over, and around ~35 once I have my lift cup attached. The thump that my slightly heavy lift makes as the shell heads up makes me grin every time, and it gets good air. Hard to say how much in the dark, but easily comparable to festival ball sized shell kits I could buy in a store.

 

If anyone tries out the shell making methods outlined above for festival balls, I sure would be interested in knowing the results.

 

Happy lighting!

[dagabu]

Hello folks,

 

I hope that my resurrection of this thread will be helpful to you guys.

 

When I just started making out 1 inch and 1.75 inch shells, I felt like I was in the dark. There is soooo little information about Festival Ball sizes and smaller out there, that it required a bit of experimentation with them until I was in the vicinity of doing it right. But what really cinched it for me was this particular PDF. ( It is the top result on the page. You'll need Google Docs and to click on 'Quick View' to read the damn thing, otherwise there seems to be something wrong with the original PDF)

 

I was initially skeptical of the what seemed like a high amount of break charge required (1/2 a TSP of equivalent Goex FFg powder in each hemisphere), but it seems that the smaller aerial shells need a harder break in order to have good form and symmetry. I use a little bit more lift than they mentioned here, 5 grams of Goex FFg to lift around the shell that weighs ~28 grams once pasted three times over, and around ~35 once I have my lift cup attached. The thump that my slightly heavy lift makes as the shell heads up makes me grin every time, and it gets good air. Hard to say how much in the dark, but easily comparable to festival ball sized shell kits I could buy in a store.

 

If anyone tries out the shell making methods outlined above for festival balls, I sure would be interested in knowing the results.

 

Happy lighting!

 

Zarwid,

 

I am afraid that I have never had an acceptable break from such a small amount of BP. In fact, I use about 5g of whistle to boost the coated rice hulls (packed in among the stars) to get good round breaks and even then the break is spares most of the time unless using mouse turds.

 

I also use 5 layers of #30 kraft on my hemis to get the shell to fracture, any less and I get large pieces of shell falling down.

 

-dag

[Zarwid]

Dag,

 

Eek, I'm afraid that I must have touted my ignorance a bit there. In all honesty, this is the first time I've tried building shells for the fourth, and I was just ecstatic when they broke and were lifted properly. I guess I was a little overly pleased and enthusiastic with the results, before I put my last post up. That, and within the inside of the shell, ~2.5 grams in each hemi just seemed to make it pretty full.

 

I'm a little confused as to just how much/what kind of burst charge should be used I guess for these smaller shells.

 

Some people use a booster like flash or whistle, and some people say it isn't necessary. Some people say that you can use commercial grade FFG to use as a burst without having to worry about coating rice hulls with meal powder, while others insist that just using meal powder with or without rice hulls. I mean, I know that your payload (stars, flying fish, crackling fuse, whatever) can differ, and I suppose that that would be a factor along with how many layers you put on the shell itself, but does that really completely account for all that variation? Isn't there some kind of general rule of thumb out there?

 

The shells I've been making are paper, and so far I've been wrapping in three layers with gummed kraft paper tape, ripped into strips that are about 5/8th's in width. I'm using 5/8 inch rubber stars that have been double-primed and cut through a screen.

 

Is there something I'm doing wrong?

[Blackthumb]

5/8" stars???

[Zarwid]

Yes Blackthumb, I have been using 5/8th of an inch rubber stars that were sliced through a three mesh star-slicing screen.

[pyrokid]

I think you would have more room for burst if you used 1/4" stars, or possibly smaller ones.

[pyrojig]

That is a great suggestion. 1/4 in should be the largest for these shells( although I have used 3/8 before). The smaller stars allow for more burst . If using plastic shells it is wise to paste or at least strapping tape them for added confinement. The break charge on these shells needs to be spicy. The paper shells are not as needy for boost, but all small shells under 3 in are best to boost heavy( some small consumer shells are even broke with straight slow flash). I find there are a few boosters that can break these , ranging from slow flash to 70/30, to whistle .

[Zarwid]

Thanks for the suggestions guys!

 

The next time I slice up stars, I'll be sure to cut them at 1/4 inch for these smaller shells.

 

Hopefully the ones that I've made will perform just fine, if perhaps a bit sloppy due to not having enough burst charge in them.

 

I'm a bit of a babe in the woods, fresh off of the Turbo Pyro boat more or less, learning how to make good 'consumer sized' shells is important to me so I can graduate to larger sizes.