spiking

[eb11]

i am making a bunch of 2 inch shells for fourth of july i am wondering if i need to spike these shells

[mathiasxx94]

It depends a bit on how you attach the end disks/seal the ends. On larger shells you would definitely get a bow-tie like effect if the shell is not spiked, but on these small shells you may get a nice break without spiking. However if I was you I would have spiked to be sure to get the best effect possible. If you are looking at the safety aspect spiking can also prevent a flower pot or muzzle break.

[flying fish]

If you are making traditional cylinder shells, where the paper walls are relatively thin and the structure of the shell is dependent on the contents inside, you will need spiking for the shell to survive lift and to get any kind of a decent break. If you are using well sealed commercial tubes it isn't necessarily necessary but like Mathias said you are likely to get a bow-tie break. I'm talking about color shells of course. Salutes must always be spiked to make sure the end disks stay one during lift, due to the more severe consequences of one blowing up in the gun (but then again you shouldn't be making those unless you have a very thorough understanding of how they are made).

 

In any case I would suggest getting familiar with the spiking process. I actually find it fun, but then again maybe I'm just a little nuts.

[eb11]

i have been spiking all my shell was just wondering if i had to i am making 400 2inch shells for 4th of july alot of work

[flying fish]

How are you making the shells?

 

There are consumer shells like KOD and excaliber that have rammed clay plugs, a machine wound casing, and an energetic burst. Those work fine without spiking. But if you're talking about casings made with 2 or 3 turns of kraft paper, I have my doubts they would work without spiking. There are also ways to "spike" that may be faster than stringing, like with filament tapes. However I haven't tried this myself and I'm not sure about how to do it or how much time you would save.

 

Another idea is just to spike it less. I would think that 8 verticals and no horizontals would at least hold the shell together. You'd have to try it and see though.

[eb11]

i dont have a problem spiking all the shells i made and tested worked great was just wondering if i could save a step. i hand make all my casing with 3 turns of 70lb kraft paper then 2 more turns of 30lbs kraft after i spike it will just keep doing my usual cant wait for the forth

[flying fish]

You could try it with a couple of shells and see what happens. If you do a proper paste wrap after closing the shell it may shrink up enough to hold everything together. I've always spiked these so my intuition could be off.

[nater]

Those consumer cans that Flying Fish mentioned also have very sloppy breaks. They are just bulk filled with stars and granulated burst, not worth trying to emmulate in my opinion.

[flying fish]

That is a very good point. The KOD shells somehow get away with loose powder as burst; I suspect one of the plugs is rammed outside of the casing and then bonded in. The breaks are OK considering how crudely they are constructed, but they don't bear anything resembling symmetry. They work if you just want a splash of color - but I figure at that point you could just buy em. Couple cases of 1.4 shells doesn't cost too much

[eb11]

i tested 1 of the 2 inch shells and i am getting like a lazy spider look the shell explodes and the stars look like a spider is there a way to get a more powerful break i did spike it. it is a canister shell Edited April 4, 2013 by eb11

[dan999ification]

I get that if the spiking or confinement are too strong for the break, they tend to dump as the casing is only partially broken, or if the paper breaks before the string, the path of least resistance is followed.

What are You spiking with?

I'd try more paste wraps,

Or lighter twine,

Or 2g of bright flake 70/30

 

Dan.

[eb11]

to build my 2inch canister shell i wrap 70lb craft paper 3 times around my former i use wood glue to glue it. to seal the ends i use 2 cardboard circles on both ends the same id as the inside of my shell i place 1 cicle into the shell then cut notches all the way around, i then fold them into the center then place the other circle ontop of that that seals the ends. i then spike the shell with hemp string then wrap the shell 3 times with 30 lbs craft papper