Breaking 3" and 4" cylinder shells

[Livingston]

so Im having issues with breaking my 3" shells! I doubt its my spikng but I could be wrong. My Bp is Hot I dont normally use booast... here take a look..

 

https://www.youtube.com/watch?v=2xQDRIk9G9g

 

This 1 of my most recent Shells..

 

Any suggestion would help a great deal thanks

[psyco_1322]

Throw in a gram or two of booster, fixed.

[WonderBoy]

I'm curious if you have any photos of the shell? And what kind of materials are you using? It didn't look like a bad break, just not a big break.

 

But like Psyco said, a bit of booster might solve your problem.

 

 

WB

[calebkessinger]

Yep, second, third, whatever,

add about 2 grams of any type of booster and see what it does for you. You can probably get away with straight 7/3 in a flashbag. or just dusted in the center. If that is what you think would be too hot just cut the perc. with nitrate. 50/50

pot nit. 35

pot perc. 35

dark alum. 30

[Livingston]

ok Psyco so what would be the way to best install the booast? like mix in with the burst or ?????

 

 

 

 

Wonder boy. the shell was made with kraft paper 3 turns 8 ply cotton string chipboard discs

 

PS that motor was made with Calebs 3/4 skinny rocket tooling

 

Thanks Guys!!!!

Edited February 21, 2015 by Livingston

[schroedinger]

There are a couple ways.

1. Just dump it into the Burst charge during building or just before closing up the shell.

2. Tumble the hulls in booster and use only what clinges to the hulls.

3. Wrap the booster in saran wrap and place the pear inside the middle off the shell.

4. A flash bag around the canulle.

 

The last method is likely to fail with most non spider ty shells. From the other you habe to test witch gives the best results for you.

[enanthate]

As you know im no expert, but i know a couple of things.

First, the kraftpaper should be used in a certain direction (grains?).

Isnt it also best to paste another layer after spiking? Ive also seen people spike 2 times, with pasting between.

And how big can the break possibly get at that altitude?? Its very high!

 

For whats its worth tho, I thought it was an awesome rocket would like to see more in the future.

[schroedinger]

Yes for a can shell you usally want the kraft to be grain short.

Spiking two times is normally done if the reinfascinating method is used. This methods uses nest to no glue, so you can fire a shell at the same day.

Pasting a shell after pasting is a controverse discussion. Some people say it is not needed on rocket headers as it doesn't contribute to the shell strengt and only needed for flame proofing. Reading fulcanelly in pyrotechnica the opposite is stated, on the other hand look at TR, or viking shells and you will find they work fine without the pasting step. This is a point where you have to try yourself if you need the paste on a rocket or not.

[psyco_1322]

Keep in mind that someone who builds cylinders for headers will likely be compensating for the loss of extra confinement the paste wrap provides. TR still has to use a bit of booster in his shells to get the breaks he does. I would be most certain the Viking probably does too. Tuning your breaks is just part of making fireworks.