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Cylindrical Shells


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#856 italteen3

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Posted 24 May 2006 - 04:39 AM

Great worksmanship! Hope it performs as good as it looks, because every new shell someone posts looks nicer and nicer by the week. Cant wait to see the video!

#857 karlfoxman

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Posted 24 May 2006 - 07:17 AM

Once again a very nice shell, is that a compartment shell or just one long one? Must be kind of scary mixing that ammount of flash for the bottom shot. Did you mix it in small batches of say 5 grams at a time? Have you ever looked in to the Maltese way of lifting shells? I tried 25g of rough powder to lift a 580g shell and it when very very high. It also nearly wiped out the plug from the mortar. Back to the nice orange mortars for a test like that! :D

#858 al93535

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Posted 24 May 2006 - 07:41 AM

Sorry post removed

Edited by al93535, 09 August 2006 - 06:06 PM.

The more I learn, the more I know I don't know.

#859 Creepin_pyro

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Posted 24 May 2006 - 08:32 AM

The Maltese use a relatively slow polverone to lift their shells. They're able to do so because they contain the lift inside a maroon - kindof like lifting a shell with a BP bottom shot instead of the usual badly-confined bag of BP grains. I'm sure someone will elaborate on their construction. Beautiful shell, by the way - can't wait to see how it performs!

#860 karlfoxman

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Posted 24 May 2006 - 08:51 AM

I will draw up a set of diagrams for you when I can, the lifting shell is spiked and then above that is a wooden disk with the same diameter as the ID of the mortar tube. Then above that is wadding made from cloth or something that can compress. Then the shell sits on that. When the lift shell ignites it compresses the wadding and creates a airtight seal, almost all the gases go into lifting the shell. I have seen up close a 6inch shell 4 feet long being lifted by a very tiny lift shell when I was in Malta.

#861 r.burgy

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Posted 28 May 2006 - 01:41 AM

please help!!!@! can anyone please tell me why i can send 1 shell up with no problem, then send another one up with the same lift and it just poofs out of the tube like i used meal powder instead of lift powder??
i cant figure this out!
its the same powder. im not changing anything. one will go boom and launch and the next will go poof and go about 8 feet. anyone help please??????

#862 Mumbles

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Posted 28 May 2006 - 02:56 AM

That is odd. About the only thing I can come up with is not having a tight enough seal with the shells. Too small a shell could possible cause indescrepancies with lift heights.

#863 fishy1

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Posted 29 May 2006 - 01:02 PM

are the shells the same weight?

#864 jhos

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Posted 30 May 2006 - 03:19 AM

I'd like to find out about making perfect star for my own mortar tubes. I can obtain enough charge for the blast...but I need help in the right directions/instructions/etc on how to make good stars. Please help... :(

#865 Jerronimo

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Posted 30 May 2006 - 06:18 PM

What are you talking about?
do you mean stars for roman candles, or shells for mortars?

Anyway, there's alot of information on both subjects on this forum, I suggest u use the search function
"Any society that would give up a little liberty to gain a little security will deserve neither and lose both."

#866 adamw

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Posted 31 May 2006 - 10:11 PM

Correct. The forum has a lot of information on making all kinds of stars. Please use the SEARCH function!
75 : 15: 10... Enough said!

#867 r.burgy

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Posted 01 June 2006 - 11:54 PM

in regards to lift height...
my shells are the same weight,but it seems like the lift is going past the shell.i recovered one of the failed shells and the outside is black and it splashes upward like the pressure is going around the shell.all im using is a cardboard cylinder(about1in)wide by 3in tall.that is my shell.attached to the top of the shell is a smaller cylinder with the lift powder in it.this is then inserted in the tube upside down.blackmatch as the fuse.it seems like it fits tighter at the middle of the whole shell.maybe this is why.im going to add thickness to the main shell instead of the lift part.hopefully this will correct the situation!!!

#868 karlfoxman

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Posted 05 June 2006 - 12:12 PM

I have been building a new cylindrical shell, its a 5 inch cylinder shell. The effect should be as follows: RED STARS AND WHISTLES ON LIFT. WHISTLES - ALTERNATE YELLOW AND WHITE FLASH RING - RING OF PURPLE FLASHES.

I have some pictures of construction, it uses 12 3/4" 4g purple flash crackers 6 3/4" 70/30 4.5g flash crackers and 6 3.8g 3/4" yellow magnesium based crackers. These are aranged in rings, the purple ring is on 2 secound time fuse and. The yellow and white crackers are on 1 second chinese dalays. The whistles are 1/4" id and are pressed with my 1 ton arbor press, these just have a black match passfire so should light almost straight after the break there are 6 of them. The break charge is very fast willow on corncob, with added 10% by weight whistle. The spiking is linen twine and then its covered in paste. The lift charge will be the maltese method of spiked shell under main shell with wooden piston and newspaper shock absorber. Also in lift at top will be some more whistle inserts and some ruby red 8mm pumped stars! :wub:

Edited by karlfoxman, 05 June 2006 - 02:00 PM.


#869 karlfoxman

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Posted 06 June 2006 - 04:46 PM

The shell is finished now, here are a few more pictures. Fingers crossed, im sure it shall be filmed :D

#870 Pretty green flames

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Posted 06 June 2006 - 06:21 PM

Looks like a mighty fine shell Karl, looking forward to seeing the maltese way of shell lifting and the shell also.




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