7" zylindrical Shell with 10 simultaneos Inserts

[Pyroboy]

Hi guys,

 

 

 

this is my latest project: a 7" zylindrical Shell with 10 inserts. Hopefully they all explode simultaneous, as planned.

 

 

 

Some Details first:

 

Weight: ca. 2kg

Lift: 100g corse BP (0,5cm-1,5cm)

Spolette timed on the upper side: 1s

 

 

Inserts:

 

Diameter: 55mm

Lenght: 70mm

Burst: Sp + 3g 70/30 Flash

Stars: Silverstreamer (15mm rolled)

 

 

Here are some Pictures of the shell building. Sorry, i could not resize them here in the forum. So i just linked them.

 

 

 

Empty Insert with burstcharge casing glued in:

 

http://www.pyrobin.c...31082010208.jpg

 

 

Inserts filled with burst and stars. not closed:

 

http://www.pyrobin.c...31082010213.jpg

 

 

Main Case with 15mm Spolette glued in:

 

http://www.pyrobin.c...31082010210.jpg

 

 

Pasted and primed Inserts:

 

http://www.pyrobin.c...07092010218.jpg

 

 

First row of inserts with enought space between them for the spolettes of the second row:

 

http://www.pyrobin.c...07092010219.jpg

 

 

Second row:

 

http://www.pyrobin.c...07092010220.jpg

 

 

Filled with burst (BP on "Dinkelspreu"/ Dinkel Hulls):

 

http://www.pyrobin.c...09092010224.jpg

 

 

Spiked Shell:

 

http://www.pyrobin.c...11092010225.jpg

 

 

Liftcharge with the Shell:

 

http://www.pyrobin.c...11102010390.jpg

 

 

Finished Shell:

 

http://www.pyrobin.c...11102010392.jpg

 

 

 

I hope you enjoy watching the pictures. Questions will be answered.

 

 

Poorly i can´t shoot the Shell before nem years eve, but you will get the video as soon as possible.

 

 

 

 

Best regards

 

Pyroboy

Edited November 5, 2010 by Pyroboy

[dagabu]

Very nice! I hope that one day I can build a shell like that!

[NightHawkInLight]

Looks pretty good. That's some darn wimpy spiking though. I hope you pasted it well. If not, open it back up and lay on a few more layers. Better to redo your lift and passfire than for your shell to fail.

[WonderBoy]

I'm with Nighthawk on this one. I would use at least 8 or 10 ply cotton string. The inserts look nice though.

[Pyroboy]

Hi,

 

I pasted 4 layers before the pasting and 2 layers after pasting the shell. It don´t need a heavy break, though it will explode while rising to the sky. The mainspolette is timed to 1 second. The inserts spolette burns 2 seconds. Total delaytime 3s. It just has to spread the inserts in a good angle over the sky.

 

 

I have an example for the effekt I wish it´ll be: http://www.youtube.com/watch?v=W81YX3YDtAU&feature=player_embedded

 

Go to minute 4.40, there are three of these shells.

 

 

 

The shell itself is stabilized by the inserts. They are standing at the bottom of the shell and the upper row is standing on the lower one. The pressure will be taken by them and not by the shellcase. For saftey I used three heavy paper disks under the shell as "Shockresorber".

So I think it will be ok with this weak strings. With thicker one the shell won´t fit in the mortar anymore, its just maximum sized.

[Mumbles]

I hope it works well for you. It should look very nice if it works. Do you always build your shells using those methods, or have you ever tried the traditional techniques?

[dagabu]

I hope it works well for you. It should look very nice if it works. Do you always build your shells using those methods, or have you ever tried the traditional techniques?

 

MUM-

 

Can you enlighten us all as to the most obvious differences?

[50AE]

The only thing I don't like is the shell body. I'm hard to convince that a spiral wounded tube will break better than a traditionally grains vertical kraft rolled one.

 

(Sorry, I relooked at the pics and I noticed that the main case is made from parallel rolled paper.)

 

Except it, the rest is very good work though! Don't forget to post a video after NYE!

Edited November 6, 2010 by 50AE

[ExplosiveCoek]

The spiking really needs work though.

[Pyroboy]

Finally I loadedup the Video to Pyrobin.

 

 

The first contains some smaller stuff, a 2" crackling comet, two 30mm bombettes, two 60mm zylindrical shells and the 7" canister. The break of the 7" was much to low and the timing could be more precise.

 

Zusammenschnitt

 

 

There are two more videos of two rockets and a 4" shell

 

Zwei Raketen

100mm Kugel