Jump to content
APC Forum

Recommended Posts

Posted

WOW, damn good shells. Break are massive for 3 inchers, any flash booster, if so how much.

 

Cheers and keep up the excelent work!

  • Replies 3.6k
  • Created
  • Last Reply

Top Posters In This Topic

  • Mumbles

    390

  • psyco_1322

    228

  • Pretty green flame

    137

  • qwezxc12

    134

Top Posters In This Topic

Posted Images

Posted

Siffup, i forgot to ask, what was the formula for the stars in the first shell in the 6shot clip, it looks very cool.

 

Thanks

Posted
muuuahhhhhh, what a crosette @ Frozentech.

damn good...............looks real prof.

you used a crosette-pump?

what you used for burst?

holy shamoly!

I used a 3/4" crossette pump from Rich Wolter for that shell, with KP on rice hulls for burst.

 

I'm working on a 6" can with 1 1/4" crossette comets now, I have to pump a bunch more ( like another 600 grams worth ) of comets before I can go any further, and can't do that till I get back home next week. Should be 'interesting' :)

 

There's a bunch of construction pics of my 3" crossette shells and a pic of that 4" shell being built at:

http://www.pyrotechs.org/content/view/18/44/

Posted
Frozentech how deep is the cavity of the 1 1/4" crosette?

 

thx

The cavity is 20mm deep. The 'pinhole' at the bottom is an additional 5.5mm deep.

The cavity is 11.4mm across at the widest point of the 'X', and 7.8mm across at the

most narrow part between the arms of the 'X'. Hope that helps.

Posted

Hi

 

Needs the exact, detailed( in the high resolution) pictures of crossette pump or technical drawing.

I will be grateful for the help.

 

sorry too offtop

Posted

What kind of formers do you guys use for making your aerial shells? I use a ping-pong ball which I coat in kraft paper until about a 1 or 2 mm wall thickness is formed, then let it dry and cut around it and slip off the hemispheres for my 1.5 inch mortar, but I want to start making some 3" shells.

What kind of formers could you use? I assume if you were to use styrofoam balls or something similar, they'd probably come in sizes of 3 inch exactly (rather than slightly less than), and you would have trouble getting sizes that would allow for the thickness of your kraft paper and possible spiking of the shell to fit in your mortar once done. Surely someone here who makes their own shells knows an answer to this?

Posted
I do believe billiard balls are about good. Usually I purchase my hemis. When I need an innner hemi, for a double petal for instance I generally just form them over plastic ball shells. If you're worried about there not being enough room for pasting, you could always paste over the inside.
Posted

Maybe lampblack is stronger than charcoal, but I have used something similar. 70-30 Perc-charcoal, and it is relatively weak. It is designed for larger shells. 8 to 10" single petals I am talking here. The dichromate would indeed speed it up, and the lampblack may perform a bit better. I can't comment specifically on this mixture, but the one I tried would be disappointing to most.

 

The bursting strength may indeed be stronger, but it may be one of those things where it needs a larger area to get up to optimal preformance. Similar to how KP is stronger than BP, but it needs a high pressure to preform in that fashion. Just burning KP on the ground is disappointing.

Posted
Looks like another test for the video file coming up. I will make 5 reports, 10 grams each of BP, KP, H3, Flash, and the Perch/Lamp.
Posted

Weird, Flash was the strongest. Whoever would have thunk.

 

The lampblack one sounded a bit sharper than KP, but seemed to have a lot less flame, which may instil problems for blowing stars blind. Chances are with my mix I used the shitty commercial airfloat, which caused the poor preformace. I now use it as a flamable filler in my comet shells and such.

Posted
He forgot to add the link part of it. I fixed it. He showed it to me earlier.
Posted

BP:75/15/10 Nitrate, Charcoal, Sulfur

KP:75/15/10 Perch, Charcoal, Sulfur

KPL:70/30 Perch, Lampblack

H3: 70, 30 Chlorate, Charcoal

Flash my flash

 

I thought the weakest to strongest was BP, KPL, KP, H3, Flash. All ingredients are commercial.

Posted

Karlos, I don't know how that effect was done but it certainly is spectacular! I've never seen a shell like that before.

 

The other jpg you has is called a bee in Japan, but we call it a hummer. If you search the web or the forum be sure to search for hummer.

 

And if you were asking if the hummer is what made the effect in the aerial shells I don't think so, but maybe, I'm not sure.

Posted
I would dare say that that effect could be obtained with a double petal shell. The outer petal would be constructed of hummers and the inner petal with many many small micro stars. Canister shells would probably be better suited for this purpose.
Posted

Honestly. it looks like the color is microstars from the tail. If you look closely at the purple one on the lower left edge, you can see it is definatly not a petal of any sort. It has a general star or crown shape to it, which indicates it comes from the Ti tail, not the rest of the shell itself.

 

Those could be one of two things. Either humers, or tourbillions, probably with a Ti tail. If you had a violent burning silver star it could maybe be a matrix comet, but I'm not sure. I have indeed seen some thick flitter stars. The only stars I have ever made that could ever get anywhere near that thick of a tail are all charcoal based. My best guess would be a hummer or tourbillion with a matrix comet on the top, or just very large hummers or tourbillions to allow for larger vent holes to let out the microstars.

Posted

Those are my favorite type of shell; they're called Farfalle. The inserts are made like "A" in Karlos' picture, but with an extra vent directly opposite the first.

 

Of course Mike S. has explained their construction, so I'll quote him:

 

Farfalle are made using a 3/4" tube, I suppose about 3" long. A solid

clay plug is pressed in one end. A hole of maybe 1/8" dia. is drilled

straight through the tube just above this clay plug, so that two holes

are positioned 180 degrees from each other. A piece of match is then

threaded through the holes. Composition is pressed in as many

increments as are necessary to fill the tube almost full, and finally

another clay plug is pressed to close it.

 

The classic composition would be something like 3 or 4 oz. of steel

filings to a pound of duPont Fine Meal. A trouble with such

compositions is that even if the steel be treated with linseed, etc.,

the shelf-life of the farfalle will be limited. You could try titanium

or ferro-titanium, but, as Don once told me, the resultant product

would not be real farfalle.

Posted
That still doesn't explain the microstars in the tail though. Honestly farfalle was one of the first things that came to mind, but I have no idea what they actually look like. I could be mistaken about microstars inside the inserts themselves, but there are several arms from that purple that are quite convincing.
Posted

Thanks guys.

Frankrizzo: I thing that 3" is very much long for shells.

 

You can see two basic types of this effects:

Stars with confused flying like this:

http://www.srs.ne.jp/~north/special/hanabi/Hanabi1.jpg

 

And stars with linear flying like this:

http://www.fireworks.de/assets/images/intro14farfalle.gif

http://www.vuurwerklook.com/effecten/images/1/image053.jpg

This is video with wanted effect with unknown spinning stars.

http://hanabin.gotdns.com:8080/hanabi/mov/2003pl_010.wmv

 

This video is from my favourite site: http://www.mb.ccnw.ne.jp/hana310/index.html

 

 

If this effect is called farfalls and tubes lookin like the A type from my pictures, which ignition type is better?:

http://img02.picoodle.com/img/img02/7/1/18...fam_4c47fe1.jpg

 

I try making any tourbs. with gypsum as the plugs:

http://img02.picoodle.com/img/img02/7/1/18...fam_364e035.jpg

I used BP with 20Al. It will be supprise for me.

Do you thing that this effect is suitable for cylindricall shells? Not for round shells?

Sory my english is low.

Thanks and bye.

Posted

Of your ignition types, A would be better. To get the full effect you need a hole completely through though, as in both sides of the tube. Just one side won't give the same effect. It gives kind of a corkscrew effect.

 

As far as round vs. cylindrical shells, it's up to you. Long inserts like farfalle are better suited to cylidrical shells due to the geometry. Small inserts such as hummers and bees are perfectly acceptable for round shells though.

 

Some of you tourbillions look a lot more like hummers to me. Tourbillions don't have holes in the middle. This kind of stuff all gets confusing though. Let us know how they preform.


×
×
  • Create New...