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Cylindrical Shells


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#166 Kembang Api

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Posted 17 November 2004 - 09:22 AM

Hi Guys,
Sorry for being late in my reply. I was out shooting some of my newer shell which all came out only the bang, thats it!!!

Skipjack: Thanks for the advice, I will try to do the thicker BP prime first and shoot it out with my star tester and see how well light.

Alany: Okay!! so you have a blinded stars as well. I did replace 25% of the KCLO4 with KCLO3 and the rest remain the same, but still blinded stars. I used a non sulfur composition to prime this star as well and the result was not too well too. Maybe I will go back with the composition and prime them with BP primer but more thicker and see the result in the shell.
Thank you for the new composition, I will try to stay with the old and if it keep failing, than I will move to your new composition.

Paul: yes I only pasted the shell in one direction and using 150 grams Kraft paper. The pasted paper was cut along the grain of the paper not the other way round. The weakest part of the shell is the center half of the shell, this is where the 2 cups meet. So I keep pasting this weaker part. I hope my explaination is understand.

Here is the picture you ask, I hope is clearer. Thank you guys.

Posted Image Posted Image

#167 broadsword

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Posted 17 November 2004 - 10:44 AM

I do not know much about shells as you will tell from my question. But, how do you know that when you launch the shell the lift charge will not blow the shell apart in the tube?
Broadsword Calling DannyBoy....

#168 moe

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Posted 17 November 2004 - 10:58 AM

Hi,

your shells look nice. But i didn't unterstand how you pasted your shells. I only did on the way how shimizu discribes it in his book. Maybe you can make a totourial on pasting shells, with some pics?!


Here is a video of my 3" shell i shot yesterday. the bursting charge was H3 (75g Potassium chlorate and 25g characol. it has been coated on Corn Cob with SGRS)

3" Shell


sorry for the miserable stars, but at the moment i'm testing bursting charges...

#169 Creepin_pyro

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Posted 17 November 2004 - 11:03 AM

You can never be completely sure of the integrity of the shell prior to launching. With spherical shells, care must be taken to reinforce the area around the time fuse/spolette to stop it from being pushed into the shell. Cylindrical shells are more liable to be damaged from the lift charge, and cushioning disks can be used to decrease the likelyhood of a flowerpot.

#170 Pretty green flames

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Posted 17 November 2004 - 02:20 PM

Kembang Api....

Do you use electric igniton to ignite your lift charge.
Cuz i see some wires on your pics.

#171 Kembang Api

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Posted 17 November 2004 - 05:18 PM

Broadsword: When I pasted the shell I make sure that the spolette are pasted as well. If you look closely on my previous photo you could see. In this picture I did cover the spolette with a tape, just for protection purposed.

Moe: okay maybe tomorrow I will take a picture of how I paste the shell and the spolette.

Pretty green flames: Yes I launch the shell with my electrical ignitor and control box that power by 12 volts battery.

#172 BurlHorse

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Posted 17 November 2004 - 07:01 PM

From Lancaster 3rd edition book. Itis mention that H3 bursting charges are used for small shell, while KP is use in medium size shell and for big shell, it is safer to use BP bursting charge.
The above statement was adopted and since than all my 3 inches shell, used KP with a ratio 7: 1. I also found that in Lancaster book, He mention to keep the ratio 80:20 which is 4:1. Before I change my bursting charge from KP to BP, I might have to adopt a smaller ratio. Thxs

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Nice work, But the Ratio's vary for many reasons which have been discussed, but of course I will throw in my 2 pence,

7:1 KP Burst, I assume rice hulls, That Makes for some Big Hulls from a Mesh Size Point of View. So while you have more of the Composition effectively as the burst, You can't fit as much of it in the shell. The 4:1 Ratio makes a much smaller Mesh Size and Therefore Hidee HO smaller = More in the interstitial spaces between the stars and more of the Comp actually in the middle of the Shell, measure/weigh it for yourself and see...... 4:1 Ratio IE; Smaller Particals are better at filling in all the spaces and making for a rattle (READ Friction Free) rattle free shell. It took Tim and I a LOOOONG time to Figure this out as He has the mentality that H3 Burst 6:1 or 7:1 is Better Than Hot Peanuts at a ball game, Only after much convincing and lab scale weighing could I prove my Point. 4:1 H3 is his Favorite Burst for 6's to 12's. He then Pastes them to the Nth Degree until they are sometimes a little hard to drop in the Mortar, I carry a Cane Just for that reason to our shoots, for a push stick haha. Some might say too strong but when you've seen Tims Willow Shells Break 1/4 Mile Wide (12" shells) and Just Keep on Trucking, it's a sight to behold.

The other thing I personally don't like about large Ratio Burst is the Remnant Dim Red Glow in the Middle of where the shell went off, it can and does ruin the symetry of some otherwise beautiful shells because it just falls out of the sky from the middle of the flower. This could Be an effect that could be usefull I suppose, for a falling leaf effect in Larger Shells.

I Like using a dark Burst, but thats my preference, I am not at home at the moment but I will Try to Find a couple of Dark Flash/Burst Comps to post for you to try using Dime (or what ever small coin would be applicable to where you are) Wrapper Flash Bags. Your Mileage May Vary, However it works for me.

You can of Course Mask that red Remmnant glow with Ti Flashbags and such, But the effect on the eye is a big white spot that for the few seconds the stars burn, all you see is a white dot, not very pleasing in my opinion either, so just some random thoughts to ponder for you guys in search of Burst/Symetry/Boom Nirvana

OH, One Last thing, in one of the Best of AFN's there is a little side line snippet about shimmering Burst, and a Ti Trailer Burst, when the shell maker was asked how he did it, he said simply, 1/2 oz Coarse Titaninium and 1/2oz Sawdust (By Volume as scoops) were used, this is put in a smallish plastic Bag, sealed and just thrown in the shell upon assembly, The Vacuum Created behind the stars as they are expelled from the shell pull the burning Ti behind the stars resulting in an interesting effect. I have tried it a time or 2 and while it was cool, it still gave that white dot syndrom though to a much lesser degree, interesting effect, relatively safe thing for you guys to try.

BY the Way, The Crackerjacks My Club is revamping some of the website, The Guy in the Middle is Yours Truly, Wiring up 50 (simultaneous Launch) 4" Salutes to Announce the Beggining of Open Shooting on Saturday. Fair Credit due, The Guy on My Left is a great Pyro friend Bill Quitman and to the right, Jimmy....uh, well, Jimmy! So take a peak and see! Shameless, Simply Shameless, but it did get everyone (Late Sleepers) out of thier tents......hahahahahaha

Stay Green,

Best Regards,

Bear
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#173 moe

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Posted 17 November 2004 - 07:03 PM

Ok,

than i will make some pictures of pasting a shell, too. there're some stars left from the last shell...

moe

#174 BurlHorse

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Posted 17 November 2004 - 07:27 PM

here is a 4" plastic ball shell 8g Flash coated Bp coated rice crispies..4" Red to Silver .Here is Shell loaded and Shell in mortar

  First Clip is filmed about 100yards away height of burst around 300+foot.. Even tho both of the Video cameras are 3ccd the first camera doesnt catch anywere near the true color a nice deep red.. the second clip is from my 3ccd camera which as a faulty mike but colors look better..that camera was placed about 200 yds away and even tho you cant see a thing thru the viewfinder i placed the camera just right to catch the break.... i think the break looks square? slow motion playback shows the top half of the stars dont seem to blow correctly....Ill post more vids when i get the time been very bizzy.....

Oh and burl horse nice to see you back ....even tho i got dave blessers book i followed  your instructions to the letter..well nearly.. :) ..

Thanks to infernolabs for hosting my clip...

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Thanks SAS, Good To Be Back and Recovering/Feeling Better!

As to the Square Looking Break, I think it's a Matter of Viewing Angle, But It Looked Great And the Color Changers were Definetley Made Well, Very Good Timing, which means very good Sorting before Next Layer Of Comp was rolled on, Very Very Impressed with your Progress.

I will Say This, From my Perspective of the Movie, It almost looks as though the Shell was already Picking up some Pretty good Gravity Induced Momentum, IE; The shell was already past it's Apex/Apogee and therefore gave the break a downward Cant. Just my opinion.

Try This,

Make an inert Shell, Sand and Sawdust to fill it to get the weight the same as your average shell weight, like this particular one. Paint it Black or Flourescent Orange, 10 Grams Of Flash to Burst it in the Day time so you can follow it up and see if it is going up or down when it Bursts. Wear Goggles while looking up as the sand will come down in a hurry and it gets blown a pretty good distance from the Point of burst

You are doing well My Friend, Very Well!!

Stay Green,

Best Regards,

Bear
There are old pyros, and there are bold pyros, but there are not very many old, bold pyros....

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#175 Kembang Api

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Posted 18 November 2004 - 01:00 AM

Sasman: Very nice shell, just love it. was it a barium nitrate core were used? than coated with red star composition. I love the color changing timing. What else can one ask for better shell, hahaha.
From the picture, it look like you have a comet or silver tail attach to the shell?
Good work Sasman!

BurlHorse: Thank you for your advice, I did test the KP 4:1 ratio and the stars did lighted but still under 30%. The noise level is a bit softer than 7:1 ratio. I will work on the 4:1 ratio again for a while.

Edited by Kembang Api, 18 November 2004 - 01:05 AM.


#176 broadsword

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Posted 18 November 2004 - 01:29 AM

Sorry toask such a noobish question :blush: but in this pic....Posted Image

I take it the shell on the left is the shell wrapped up and I am assuming this bit is the only part that leaves the tube?
Then can someone expalin the other stages please? Will the fuse always light from the lift charge?
Thanks, Ian
Broadsword Calling DannyBoy....

#177 Kembang Api

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Posted 18 November 2004 - 03:52 AM

Broadsword: The picture show the steps on how the lift charge bag is covering the spolette to asure the spolette (fuse) will be ignite and how the e-match is install into the lift charge bag and finally the paper cone to protect the shell and also to keep a good distance of the shell to the bottom of the mortar.

#178 BurlHorse

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Posted 19 November 2004 - 08:14 PM

Sasman: Very nice shell, just love it. was it a barium nitrate core were used? than coated with red star composition. I love the color changing timing. What else can one ask for better shell, hahaha.
From the picture, it look like you have a comet or silver tail attach to the shell?
Good work Sasman!

BurlHorse: Thank you for your advice, I did test the KP 4:1 ratio and the stars did lighted but still under 30%. The noise level is a bit softer than 7:1 ratio. I will work on the 4:1 ratio again for a while.

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Good, And Thanks, Keep Up The Good Work, It looks like Your Moving At a RAcers Clip now, The Shells Look Great and The 4:1 Will Work for you, Just have to dial it in so to speak.

Regards,

Stay Green,

Bear
There are old pyros, and there are bold pyros, but there are not very many old, bold pyros....

Check Out My E-Bay Auctions !!

#179 paul

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Posted 20 November 2004 - 12:10 PM

Today I finished my new 4" cylindrical shell.

4" cylindrical shell 1
4" cylindrical shell 2
4" cylindrical shell 3

I used 40g of CIA blackpowder for lift. I?m going to shoot this and other ones together with moe next week.

The shell is filled with nice silverstreamers, willow stars, willow to silverstreamer and a few 20mm pumped stars. Hope it?ll work :D

I?ll keep you informed.

#180 sasman

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Posted 20 November 2004 - 12:43 PM

That shell looks BIG! How much does it weigh? ...Hope you get it on video..




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