1569 replies to this topic

[Creepin_pyro]

Very nice, indeed . The break symmetry and star ignition seemed good - perhaps a more violent break would have given a fuller effect, but I'm not sure. Personally, I would like to have seen a harder break, but it was still a beautiful shell.

I would estimate +150feet, but I'm really not sure about that.

Thinking about breaks..... Why not use coloured flash bags? Never seen it before, and I'm sure it would be a nice effect - a nice red burst followed by the tiger tails.

[sasman]

ha

Edited by sasman, 25 October 2010 - 09:10 PM.

[Yugen-biki]

Very nice shells!

The shells are not bad in any way but here is something that can be shanged:

As Creepin_pyro sad, a stronger burst makes the "flower" bigger and more effectfull. This is what I think.
I allways fill my shells with the maximun ammount of burst possible. But you should try to make the shell case stronger. And the burst will become bigger without very much work put down and chemicals spent.

One other thing is the star burn time. I know this is had to solve but some stars tend to travel longer then others.

Personally I don't think enything on your shells need to be fixed. After time you will become more skilled and the shells will become better.
I have never used plastic, but I have read some about them. What I understand a flash bag might be better used in a plastic shell. A lot of info on flash bags can be found in AFN.

This is a picture of my last year 3" shells, and this year I will put some time on my 4" developements.

[italteen3]

VERY nice Sasman. You seem to be advancing rather quickly in the field of pyro. Have you tried fiberglass strapping tape? I was talking to Harry from Skylighter a while ago and he said he has seen plastic shells rivaling japanese paper ball shells which used that tape.

Yugen those shells look very professional looking. Have any vids?

[sasman]

ha

Edited by sasman, 25 October 2010 - 09:10 PM.

[italteen3]

Yugen-biki you are right about making the shell stronger .this is part of the shell that landed a a few feet away from me .Shell Half and Shell half 2 ..its plain to see that i didnt glue the shell halves together properly...From now on i will clamp the shell halves together and wait until i cant dent the seam with my finger nail as burlhorse said.. i only let the glue dry for 1 day..

  .Also Does this mean only half of my stars were ignited? i have counted 73 lit stars and i put in at least 120? to 130 ..The shell half is totally intact so i am amazed the break looked ok?  I have also worked out the height of the Burst..

..Using Adobe Premier to count the frames of the video i got the following
1.  Flash of shell to Bang! 18 frames
2 Flash of the mortar to the Bang 8 frames
  So if speed of sound travels at 1100 feet pers sec... there are 25 frames per second so 1100/25= 44 feet per Frame
So 18 frames x 44 Ftpersec = 792 feet distance from Shell to camera
Distance from mortar to camera 8 frames x 44Ftpersec = 352 feet
So height of burst = 792 - 352 = 440 feet high approx?

Does that sound about right? 4" shell should be fired to about 400 to 500 feet?
And italteen3 i am going to order some Fiber glass strapping tape now that i can see its very important to make sure the shell casing is very strong..I had used gummed paper to help strengthen the case ..

Your calculations seem to be right to me.

From www.Japan-fireworks.com it said a 4" ball shell about 160 meters. Figure rougly 480-500 feet. So I dont think 40 feet lower should make a big difference unless you have a nice LONG hanging willow.

Im not sure firsthand if the fiberglass strapping tape will be superior to gummed paper but it is what I have heard from a respectable source. It couldnt hurt. Goodluck and keep us updated I enjoy watching your vids!

[Yugen-biki]

italteen3

Thanks! The bad thing is that I don't have a very good camera to make videos. Kaboom..swosh..bang and some blurry bright spots. Not vey good videos at all.

sasman
I have used some different gummed papers and tapes, but in the end ordinary white glue and sturdy kraft paper is the best. At least when makeing shells made only from paper. My 3" shell walls were just under 10mm thick. And I am sure more paper would not do any harm.

About the stars. Did you use a prime on the stars? This becomes very important when the burst gets stronger. You can coat the stars useing the burst charge (H3, BP...). I have found 1-2mm primeing to work good for me.

And one thing about the hight:
If you are happy with the shell, thay are good. I used to thing the shells became more beautiful a higher altitudes. But I soon found out that this is not the case. If you can see the burst clearly and stars don't fall on the groud or trees the hight is good.

[I don't dare post more pics, I'm a paranoide person ]

[sasman]

he

Edited by sasman, 25 October 2010 - 09:11 PM.

[Yugen-biki]

Wow!

I think your shell was very beautiful!

Just a thought:
If you use something stronger then BP and/or more pasteing, I'm sure the "flower" will get bigger. Not very much extra job put down to get the most effect out of the shell.

[alany]

That's great!

If I made a shell like that I'd be pretty darn happy. Nothing wrong with a dense break, but you could try a whistle booster rather than flash if you want it a big bigger, but I really don't think it needs it. Then again, the scale is difficult to judge in the video.

The comet seemed to work? I doubt the timefuse would have left that big of a trail.

[sasman]

I want to try whistle mix as a burst charge , I have tried potassium and sodium benzoate also sodium salicylate standard 70:30 mix with KCLO4 .

I have ground both chems seperately into a nice talcum like powder then screened them together to make sure there well mixed but when i have burnt small samples of either mix they dont burn as fast as my BP?..So i have not used whistle yet .. How fast should whistle burn should it go whoomp!! like Flash powder?..If i use Potassium chlorate with either benzoate or salicylate then that does go with a whooomp!.. The comet was made of some the star comp so should have had a nice silvery tail.. but for some reason it just seemed to smoulder..still it was good enough for a guide for my GF to film

but you could try a whistle booster rather than flash if you want it a big bigger, but I really don't think it needs it.  Then again, the scale is difficult to judge in the video.

The comet seemed to work?  I doubt the timefuse would have left that big of a trail.

[Steve]

Whistle mix burns seriously quickly, and is probably closer to a poor flash than bp. I wouldn't reccomend mixing too largeer quantities of Potassium Chlorate into many whistle mixes as you can make some very sensitive compositions.

Steve

[Creepin_pyro]

Brilliant! Lovely shell there!

Just trying to think of suggestions, but it looked pretty enough to me Perhaps the height would allow for slightly bigger stars and a hideously violent burst charge, but I don't think this is nessicairy or sensible

Good luck with your smaller shells - can't wait for some more footage.

[Rip Rap]

I have ground both chems seperately into a nice talcum like powder then screened them together to make sure there well mixed but when i have burnt small samples of either mix they dont burn as fast as my BP?..So i have not used whistle yet .. How fast should whistle burn should it go whoomp!! like Flash powder?

The burn rate of whistle depends greatly on pressure. Loose, powdered whistle composition, burnt in the open tends to just flare up - as you say slower than BP.
However! Take the same powder & confine it, in a sealed card tube for example - you have one very loud report!
As soon as the pressure builds within the tube, the burn rate accelerates exponentially.
Don't be fooled by its apparently "tame" behaviour, when burnt in the open.

[sasman]

hm

Edited by sasman, 25 October 2010 - 09:12 PM.