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Inserts for large shells


AzoMittle

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Hey (again) everyone!

 

So, as per my other post (Troubleshooting 1lb rockets), I am getting ready for the next club event. Plan is to build less but with greater attention to detail, I'm focusing on 12-inchers.

 

I really, really want to do a 12" with multiple petals of timed inserts, specifically flash. The timing is what will make the effect so I'm planning to use 1/4" time fuse, and was hoping to use some 1/4" I.D. x 2" long cardboard tubes for ease. My question is, will these be an appropriate size for a 12" shell? Will they be too small / is there a certain amount of flash to use for a given size? If so my backup plan was to make Fulcanelli style saettines but those are very time consuming and I don't like the idea of ramming down on flash, even gently.

 

Or, am I totally off-base and missing some easy way to do this all together? Should I cross-match the time fuse on each insert? Anything else you can think of that I should be aware of?

 

Also, this is going to eat up a LOT of time fuse, does anyone have a good source? The cheapest I found was about $1.50 per foot (without taxes or shipping or anything).

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Azo, Im still pretty new to this but I would think those 1/4" cardboard tubes would be pretty small for a 12" shell unless you really let them drop low. Im not sure how well they would handle the break either. You would also need ALOT of them for a 12" shell. You might actually save time making larger salute inserts.

As far as time fuse goes there's a few places I know of.

 

http://www.pyrocreations.com/ignition-and-fuse/chinese-times-fuse-3-sec-per-inch-10-ft-1-4-inch.html

 

http://www.thepyropro.com

 

http://starr-fireworks.com/store/time-fuse-50-meter-rolls/

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Azo, Im still pretty new to this but I would think those 1/4" cardboard tubes would be pretty small for a 12" shell unless you really let them drop low. Im not sure how well they would handle the break either. You would also need ALOT of them for a 12" shell. You might actually save time making larger salute inserts.

 

They are 1/2" O.D. by 1/4" I.D. I think the walls would survive the break. Wouldn't be hard to make them for sure though, bundle them all together and fill them all at once Chinese-style.

 

I'm definitely worried about them being too small though. The only way I know of to make salutes (I don't mess with them much) is the traditional Fulcanelli/Italian cylinder shell style which I'm hoping to avoid, any chance you know of an easier way that still produces reliable results? Any recommendations on how large I should make them? For a 12" shell I would normally make 1" rolled stars; I want to get a timed ring effect, somewhat similar to this.

 

Thanks for the links! That's exactly what I was hoping for!

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Is this going to be a cylinder shell or a ball shell? If its a cylinder shell other then just finding some larger of the shelf tubes, Im not sure with out making your own.
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Then Im afraid I won't be much help. The little knowledge I have about shell building, is limited to cylinder shels
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Starr fireworks would be who I would get my time fuse from. You can't beat their prices. The 1/4 inserts will most likely be way to small for a 12" shell. I know in a 1/2" inside diameter tube I can get 5 grams of flash into after the ends are plugged and time fuse is inserted. You can see one of the inserts I shot by itself here

It sounds loud but it's only at about 150 feet or so. A 12 is gonna be way higher than that. And that size tube is double what you wanna use. I have never built a 12" ball shell but those tubes in my opinion would be too small.

Adam

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I agree with others that the 1/4" inserts would be too small.

 

Something else to consider is the symmetry you could achieve using cylindrical inserts in a ball shell. I think cylindrical shells are much more well suited to carrying cylindrical inserts.

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Sounds like everyone is in agreement that 1/4" is too small. But then, what would be an appropriate size? Even a guess would help.

 

I have a 2.5" 3-in-1 comet pump from Wolter and I know those are too large to fit comfortably (works great for a saturn ring and/or rising tail). I've done dragon egg/crackling cores inside rolled stars in the past but the timing on those is too inconsistent.

 

I don't mind making small salutes, saettines, or bombettes but I'm not sure what size to make them or which one would work best. I'm not trying to make a thump junkie shell, just want a somewhat solid 'pop' and flash of light with precise timing, the fuller the petal the better.

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If your trying to make a ball shell like the canister video you added maybe you could try 11/2" ballshells for the inserts. That's about the smallest hemis I think they have available for purchase. Im not sure how symmetrical the break and rings would be or if you could even fit 3 rings in that 12" casing. That's where I would start. I have made salutes in a 1.75" casing before and they were loud enough for inserts in a 12" shell I would think. Just my opinion like I said before I have never made a ball shell bigger than 6".

Adam

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Passfire.com has an "insert calculator" that will allow you to see how many of a particular o.d. insert you can get inside a particular i.d. shell.

 

Lloyd

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I would agree that you're probably going to need something significantly larger in terms of insert size. A 12" shell will probably be at least 1000 feet in the air, if not more. Small inserts aren't going to cut it at that altitude. I'd be looking more into the 1.5 to 1.75" OD realm on the larger end, and probably 3/4" or 1" OD on the smaller end. You probably want salutes with minimally 5's to 10's of grams of flash in them each. The bigger end of inserts I mentioned could probably hold 30-60g of flash at least. The size you mentioned might be alright for an inner petal, but probably wont be particularly audible. Adding Ti to the salutes is a little trick to ensure they don't get lost or overlooked even if the sound doesn't really carry.

 

Either way it is going to be a lot of time fuse. I second Starr. I don't recall the cost, but it's low. Probably around $7-10 a roll, but definitely less than $15 per case. I believe Flying Phoenix often vends fuse as well if you were planning to build everything on site. It's the same or similar fuse to what is offered by Starr and Pyropro.

 

I would definitely crossmatch or top hat or do some sort of reliably priming for every insert. Raining unlit inserts all over shooting fields tends to make people unhappy if they need to clean them up, or find them by surprise later.

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Perfect, that should be what I need to get chugging along on this project. Huge shout out to Flying Phoenix by the way, love those guys and all they do for us!

 

I always do a NC-BP slurry prime (hasn't failed me yet) but was considering punching and cross-matching on top of that. Need to get my hands on another 12 hemi first but once I do I'll grab a compass and mark out the different sizes you mentioned Mums. Figure out what looks about right, then reduce the size for the inner petal. I'd like to get 3 petals if possible, it will probably have to be something like 1.5" salutes --> 3/4" --> 1/4" or crackling stars.

Edited by AzoMittle
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Are you looking to make a display of concentric rings of inserts? I'd imagine that you'd only see that if the inserts were all placed on one plane inside the shell. If you plan on doing that, you can definitely do that with tubular inserts, as you can see here. Mr. Davis makes some very impressive ball shells that feature these report inserts in addition to a full break of color.

 

post-12911-0-82158000-1495866657_thumb.jpeg

 

 

Cylinder shells naturally break into a ring-like shape, so getting concentric rings of inserts is achieved simply by fitting them tightly in their rings and timing them crisply. Here's a really nice one by Scott E.

 

https://youtu.be/Xlbb_dD_BIQ?t=63

 

 

Edited by Wiley
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@Wiley Basically, but instead of rings it would be spherical, and I want each petal to have separate timing (kind of like a ghost shell). I found a 12 hemi and marked out varying sizes on it using a compass, turns out I have a LOT more space than I initially imagined; I think what I'm going to do is (outer to inner) 2.5" cavity comets (with flash in cavity) --> 1.75" (nominal 2") salutes --> 1" salutes (or something to that effect), with rising splitting comets (using the same cavity comets). A 12" ball shell will fit twelve 2.5" around the hemisphere.

 

I don't mess with salutes or flash much (a little, mostly for burst enhancer, and even then I prefer TPA or whistle) so I want to make sure I'm going about it the right way. I'm seeing ways to do it with spiral tubes, with hand rolled tubes, etc. and not sure which method would work best (or at all to begin with). Also, is there a difference between a salute and a report? Seems to be the same thing.

Edited by AzoMittle
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