Jump to content


Photo

Cylindrical Shells


  • Please log in to reply
1569 replies to this topic

#601 sasman

sasman

    Sasman

  • General Public Members
  • PipPipPip
  • 490 posts

Posted 11 November 2005 - 10:23 PM

That pasting look very nice!..Why 2 fuses ? is that to eliminate missfires?.. Look forward to seeing the Video...KarlFoxman Have you got a video of your 5" shell you made a few weeks back?..

#602 karlfoxman

karlfoxman

    Resident Maltese shell builder

  • General Public Members
  • PipPipPipPip
  • 1,139 posts

Posted 11 November 2005 - 10:43 PM

That pasting look very nice!..Why 2 fuses ? is that to eliminate missfires?.. Look forward to seeing the Video...KarlFoxman Have you got a video of your 5" shell you made a few weeks back?..


Sorry sas, me and wazi shot 10 of our shells but my dad was not there to film. I tell you what tho we both wish it had been filmed, they were amazing. The ring shells were perfect, i mean they looked like proper cat 4 ones!! The break charge we used is perfect for 3,4 and 5 inch shells. I have another test session to do with waz in a few weeks, there will be 2 of my 5inch shells, and 2 of my 4 inch shells plus a few extra 4's from waz. Also they WILL be filmed so you can all see our work, trust me we have both come a very long way in shell building. Just goes to show you cant just go out after reading all the books and have a perfect shell, it takes lots of time and hard work. Its worth it tho, seeing quality home made stuff is mind blowing! I am also thinking of trying some calcium carbonate orange pill box stars arranged in a ring with tiger tail peony shell....what ya think?

Karl

#603 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 12 November 2005 - 10:46 AM

Hello again!

Jep sasman this is my very first 6" shell and I really don?t want a "thump - wait - wait - wait - *shell hitting the wet field sound*" effect with my first real shell :D

But my main problem is if I can trust my two spolettes. 4cm bp hammered in seem soooo weak if you see that it has to withstand 150 or 200g of "exploding" black powder :D

I think I?ll cover them both with a piece of cardbord with each 3 strands of blackmatch in it.

Maybe one is interested in the method to produce well coated paper for pasting a shell the right way. I myself had many problems with selfmade wheat glue but now I found out how it works correctly :D

First, one has to fully cover the workbenk or pasting-board with a thin layer of wheat paste with a brush.

Then, lay down 28 strips of your cutted paper.
http://www.kkpaul.rp...g/pasting_1.jpg

And cover them with much wheat paste, too. Let it soak for a minute or so then.

I found pasting with these strips very challenging because they are so damn slippy. So, remove the rest of the wheat paste on top with a wide scraper:

http://www.kkpaul.rp...g/pasting_2.jpg


These strips:
http://www.kkpaul.rp...g/pasting_3.jpg are then perfect to work with. Use the strips upper side to paste it to the shell.


Hope this helps some of you to work with the very cheap but almost perfect self made wheat paste!

Edited by paul, 12 November 2005 - 10:47 AM.

My flickr photo album


My first very own firework pictures are online!!!

#604 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 13 November 2005 - 12:58 PM

I?ll shoot the big 6" together with a 3" so get a relation how big the difference is :D

The 3" will be one of these:
http://kkpaul.rpgame...ll_pasted_1.jpg
http://kkpaul.rpgame...ll_pasted_2.jpg

But I think I?ll take the spiked.

Looking forward to shoot these sweeties :D

My flickr photo album


My first very own firework pictures are online!!!

#605 Jerronimo

Jerronimo

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 345 posts

Posted 13 November 2005 - 07:10 PM

Very, very nice shells Paul.
I hope you can catch them on film, would love to see them in action.

Will be testing a 2'' ballshellrocket with blue and purple stars soon and will try to record it on film.
"Any society that would give up a little liberty to gain a little security will deserve neither and lose both."

#606 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 14 November 2005 - 01:01 PM

Jeah Jerronimo, would like to see a video of these rockets! I?m not into rocketry although I am interested in this stuff.


My shell is ready to fire by now. But I don?t know if 120g of black powder (milled + riced = extremely fast stuff) is enough to lift 1,25Kg.

Any help appreciated!

EDIT: I finished the shell and decided to use "only" 125g of black powder as lift. Theres not much space between shell and mortar, so I think it?s ok.

http://www.kkpaul.rp...de/P1010001.JPG

Two charcoal streamers on top. And a string to get it into the mortar. Want to shoot this this week. Hope it works :D

Edited by paul, 14 November 2005 - 02:09 PM.

My flickr photo album


My first very own firework pictures are online!!!

#607 Kembang Api

Kembang Api

    Member

  • General Public Members
  • PipPip
  • 101 posts

Posted 14 November 2005 - 03:38 PM

Paul: Since you have not try your lift charge with that kind of weight. I would recommend that you should make a dummy shell with the same weight and fire them, so you will know the height.
Shell is not a toy! From the way you mention about your lift charge (black powder (milled + riced = extremely fast stuff), I am kind of worry.

#608 karlfoxman

karlfoxman

    Resident Maltese shell builder

  • General Public Members
  • PipPipPipPip
  • 1,139 posts

Posted 14 November 2005 - 04:08 PM

Jeah Jerronimo, would like to see a video of these rockets! I?m not into rocketry although I am interested in this stuff.
My shell is ready to fire by now. But I don?t know if 120g of black powder (milled + riced = extremely fast stuff) is enough to lift 1,25Kg.

Any help appreciated!

EDIT: I finished the shell and decided to use "only" 125g of black powder as lift. Theres not much space between shell and mortar, so I think it?s ok.

http://www.kkpaul.rp...de/P1010001.JPG

Two charcoal streamers on top. And a string to get it into the mortar. Want to shoot this this week. Hope it works :D


For lofting a 5inch i use 65g, even that is lots. My 5's weigh on average 500-600g, 120g is a lot of powder, being riced it might turn to dust burn too quick and kill the mortar. Hope it works though, be sure to do a dummy test.....it will take away the doubt of it being too much/too little (i doubt its too little but you never know) GOOD LUCK MATE!! Got 700g of burst made now to start filling my shellls up, i have also go back to some of the more beautiful and cheaper effects - charcoal streamers!!! Also more unusual pill box stars, watch this space guys :rolleyes:

#609 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 14 November 2005 - 07:10 PM

Paul: Since you have not try your lift charge with that kind of weight. I would recommend that you should make a dummy shell with the same weight and fire them, so you will know the height.
Shell is not a toy! From the way you mention about your lift charge (black powder (milled + riced = extremely fast stuff), I am kind of worry.


Thanks for the constructive criticism! You?re right in a way as I really have not tested with this amounts before.
But sometimes you have to dtermine your ratios yourself if you are not able to test before. I did that with all my 3" shells, too.

Of course 6" is a much bigger calibre. But I am DEFINATELY aware of the fact that a shell is not a toy, to quote you.
I?m in pyrotechnics for a long time now and I do whatever I can to prevent accidents or something. The mortar tube is a fibreglas tube which is very stable and will be buried about 40cm into the field.

I am going to be about 150m away from it when it fires.


with best regards,

paul


EDIT: Had a look @ passfire?s autopsy section recently. The commercial 6inchers all use about 80 to 130g of commercial blackpowder. The powder they use will be much faster than my stuff, I think. Although it is pressed and granulated it will be better (in the meaning of more powerfull) than my stuff. So I am quite confident that it will work just fine.

Just hope the spolettes are good enough to hold the force of the lift....

Edited by paul, 14 November 2005 - 07:22 PM.

My flickr photo album


My first very own firework pictures are online!!!

#610 Kembang Api

Kembang Api

    Member

  • General Public Members
  • PipPip
  • 101 posts

Posted 14 November 2005 - 08:01 PM

Great to know that you are aware of the situation. My worry is only the ricehull and the black powder mix for a lift charge.
I only press and granulated all my lift charge with some grafite mix (small amount).
Regards,
Kembang api

#611 sasman

sasman

    Sasman

  • General Public Members
  • PipPipPip
  • 490 posts

Posted 14 November 2005 - 08:22 PM

I have just looked at my first and only 6" shell that i made last year..I used 70 grams 3FG homemade BP for lift. the shell weighed in at just over 3 lbs.. and it went pretty high...

I didnt do a dummy test because my lift is pretty consistant..But if your not sure of your lift powder then a dummy test would be the best way to go...Looking forward to see the video.. :)

#612 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 14 November 2005 - 08:47 PM

Theres the mistake you did, Kembang Api :P

I said "riced" bp not black powder on rice hulls :D Riced bp is meal +2% dextrine pushed wettened through a sieve :D

Of course I know that ricehulls/bp would be WAY to energetic and too fast.

regards,

paul

My flickr photo album


My first very own firework pictures are online!!!

#613 paul

paul

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 722 posts

Posted 16 November 2005 - 09:57 PM

Good evening everyone!

Today, we shot my first 6" ball shell. O M G, for me it was the most amazing thing I ever build because of its size and its construction.

Here it is.

http://www.kkpaul.rp...ch_firstone.mpg
http://www.kkpaul.rp...ch_firstone.wmv

Two formats so that people don?t have to ask for other formats because they can?t read it :)


What do you say?! I was impressed!

My flickr photo album


My first very own firework pictures are online!!!

#614 sizzle

sizzle

    Pyro Forum Regular

  • General Public Members
  • PipPipPip
  • 600 posts

Posted 16 November 2005 - 10:21 PM

Wow, that was excellent, well done Paul. :D
Category 4 Trained to BPA Level 1 Equivalent.

#615 JamesH

JamesH

    Member

  • General Public Members
  • PipPip
  • 154 posts

Posted 16 November 2005 - 10:36 PM

Thats a fantastic burst Paul, very symetrical! Those Al/charcoal stars are beautiful. Good work!
Did you shoot the can shells?
HE WHO HATH ONCE SMELT THE SMOKE IS NE'ER AGAIN FREE




4 user(s) are reading this topic

0 members, 4 guests, 0 anonymous users