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lift charge granulation


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#1 tiger tiger burning bright

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Posted 15 July 2004 - 06:56 AM

hey everyone, im making roman candles, can u use meal powder for the lift charge?

#2 miniskinny

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Posted 15 July 2004 - 08:00 AM

I made a 4-shot roman candle, with 4 barrels, and for the 1st charge on each, I had meal powder, with a paper over over the powder, and the star sitting on the paper. It made quite a report, 4 barrels going off at once, but the stars went some 100 feet in the air. So I suppose you could use meal powder.
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#3 Phoenix

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Posted 15 July 2004 - 09:07 AM

If you want to make a roman candle of the type where all the shots are stacked up on top of eachother in the same tube, whether it has rammed candle composition delays or a long fuse with sawdust fireblocks, then no, as meal powder will compact into one single grain, which will burn from one end to the other over a period of a second or two (just like the candle composition delays), rather than all be consumed in a few milliseconds like a granulated charge. The result will be that your stars never leave the tube, and you get a fountain like device, or at best they will go a short distance into the air.

However, as miniskinny said, you could, in a pinch, make a cake using meal powder (which is slightly different as it has multiple single shot tubes, but the effect is basically the same). Even so, your results will not be as consistant as they would be if you used a granulated powder.

BTW, I have only lifted small stars with meal powder. I think if you lifted anything large with it (say, over 20mm?) then you would run into problems with meal powder, as it may burn too fast.

Edited by Phoenix, 15 July 2004 - 09:09 AM.


#4 tiger tiger burning bright

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Posted 16 July 2004 - 02:31 AM

what are some KISS tecniques to make granulated LP

(KISS meaning keep it simple stupid)

#5 Guest_Warrenizer_*

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Posted 16 July 2004 - 03:04 AM

you could put it through a screen. i think the process is called ricing. there was a good tutorial on someone's site, but i dont remember whose.

basically, you just mix the meal with some water and push it through a screen to get the grain size you want. it shouldnt be wet enough to stick together like spaghetti.


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#6 miniskinny

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Posted 16 July 2004 - 04:26 AM

To add onto what Warrenizer said, you'd push it through the mesh screen (Buy some here), after adding a small amount of Dextrin and water, and dry the grains like stars. Anybody have any advice for making your own mesh screens without buying the expensive ones above?
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#7 Phoenix

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Posted 16 July 2004 - 08:52 AM

I just use a normal kitchen sieve for ricing stuff, since I don't want to mess up my good screens, and the rounded shape of the sieve actually makes it easier to force the dampened powder through.

I got my screen cloth (made my own frames) from Steve very cheaply.

#8 Dan

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Posted 16 July 2004 - 01:02 PM

To add onto what Warrenizer said, you'd push it through the mesh screen (Buy some here), after adding a small amount of Dextrin and water, and dry the grains like stars. Anybody have any advice for making your own mesh screens without buying the expensive ones above?

I just use a 6" kitchen strainer when i use this method.

#9 phildunford

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Posted 17 July 2004 - 03:18 PM

Homebase in the UK have some 'screen type materials'. There are various grades of Expanded Metal.

These can sometimes be useful for coarse screening and I use them to separate media from BP.
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#10 Zinginex

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Posted 19 March 2007 - 05:52 PM

Does the mesh size matter for granulating bp as my sieve is pretty high mesh. I heard that the lower the mesh of the sieve is when pushing dampened bp through the seive makes better granulated bp.

#11 cooperman435

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Posted 19 March 2007 - 06:06 PM

Ive currently got quite a bit of 100 mesh going spare (and cheap) anyone want some email me and I can send some in the post

#12 Frozentech

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Posted 19 March 2007 - 06:48 PM

Does the mesh size matter for granulating bp as my sieve is pretty high mesh. I heard that the lower the mesh of the sieve is when pushing dampened bp through the seive makes better granulated bp.


Mesh size affects burn rate in a lift charge. I try to sort lift powder into mesh sizes roughly equivalent to commercial BP grain sizes. I found out the hard way that a given weight of 10-20 mesh would flowerpot a shell, where the same weight of 4-10 mesh would more gently loft it up 300 feet plus. I now use 10-20 for 3" and smaller shells, 4-10 for the larger ones.
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#13 BrightStar

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Posted 22 March 2007 - 04:24 AM

I now use 10-20 for 3" and smaller shells, 4-10 for the larger ones.

Frozentech, very interesting - this is just my current challenge...

I'm looking for good techniques for making large grained dextrin bound BP lift (4-10 mesh) without a press. I have found this to be more more tricky than making the fine 'grated through 20-mesh' stuff, as making big grains seems to require more dampening and tends to end up as sticky mess...

I had considered dampening the meal + dextrin, spreading it on foil (rather like cut stars) and then corning (ie smashing it up) when dried into a solid cake, screening to remove the fines. Any thoughts?

Edited by BrightStar, 22 March 2007 - 04:31 AM.


#14 Frozentech

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Posted 22 March 2007 - 07:27 AM

Frozentech, very interesting - this is just my current challenge...

I'm looking for good techniques for making large grained dextrin bound BP lift (4-10 mesh) without a press. I have found this to be more more tricky than making the fine 'grated through 20-mesh' stuff, as making big grains seems to require more dampening and tends to end up as sticky mess...

I had considered dampening the meal + dextrin, spreading it on foil (rather like cut stars) and then corning (ie smashing it up) when dried into a solid cake, screening to remove the fines. Any thoughts?


Some people recommend pushing the slightly dampened meal powder through "hardware cloth", a US name for 4 mesh screen that is sold in rolls at hardware stores ( used for fencing out vermin from crawl spaced under buildings, up eaves, etc ). I think that if you rolled the damp meal out like a presscake, perhaps with a rolling pin , quite thin so it could dry rapidly, that corning that should work very well.

I think that most of the advantage of pressing and corning BP is in the inproved durability and the repeatability of the lift charges.
"The word unblowupable is thrown around a lot these days, but I think I can say with confidence..."
KAABLAAAMMM!!!
"OK... that shows you what could potentially happen."
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#15 Caramanos2000

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Posted 31 March 2007 - 06:14 PM

I would like to know when is my Bp fine enough for granulating it? And is 2% dextrin good for this or is it too much?




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