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BP Granulation made easier


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#1 Mortartube

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Posted 18 September 2011 - 07:27 PM

I have been pressing my milled Elder BP + 5% Dextrin into pucks (Using 10ml water per 100g comp and mixed in ziplock bag), and granulating in the usual way of breaking it up when totally dry. This is hard work and I have found and easier method.

Press into pucks using the water to comp ratio that I have given. Straight after pressing, put the puck on a sheet of card or paper. Then take a NEW craft knife (the type with snap off blades) and chop a puck into slices, then rotate it 90 degrees and cut it into roughly the grain size that you want.

When the puck is roughly granulated, extend the blade fully and chop the grains into more accurate grain sizes. Just lift the blade and chop up and down as if you were chopping a pile of garlic.

Spread it out on the paper and allow to dry for overnight. Sieve grains into required sizes and it's done. It's a lot easier than trying to break a fully dried puck and it produces less meal than the bashing method. Grains dry acceptably hard.

Seems to work for me and takes less time and produces more of the grain size you want than bashing.


ON A SAFETY NOTE. I SUGGEST THAT YOU DO NOT USE THIS METHOD IF YOU GRIND CHEMS IN A COFFEE MILL IN CASE OF STRAY STEEL FRAGMENTS FROM THE BLADES

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#2 Vic

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Posted 18 September 2011 - 10:05 PM

I do much the same, breaking up the pucks almost immediately but using less dextrin (3%).
But it is rarely I need that hard a grain, to my mind it has a somewhat slower burn rate than the push through screen method, that gives you more of a lighter and open grain.
If you were making Roman candles in the traditional way you need hard grains to withstand ramming and that is the only time I would use that hard of a grain,
but if you are a purist you could use it for all your granulation needs whilst being a whole lot more of a robust structure than the screening method.
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#3 Guest_PyroPDC_*

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Posted 18 September 2011 - 11:02 PM

may i ask, i have never used any binder or water to make my pucks, i just put it straight in the press and it comes out rock hard the smash it and sort out in size. ready to use


is this a different way than standard press, i assume you use wide but thin pucks (mine are 2" wide 1.5" deep its seems to work for me but just wondered if the dextrin changes the grains in anyway

Edited by PyroPDC, 18 September 2011 - 11:03 PM.


#4 Bonny

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Posted 19 September 2011 - 03:05 AM

may i ask, i have never used any binder or water to make my pucks, i just put it straight in the press and it comes out rock hard the smash it and sort out in size. ready to use


is this a different way than standard press, i assume you use wide but thin pucks (mine are 2" wide 1.5" deep its seems to work for me but just wondered if the dextrin changes the grains in anyway



I do mine the same way, but thinner. I make 3" diameter but about 1/4 to 3/8" thick. No dextrin, why slow the powder down ? If you're pressing, the dextrin is not needed. I have never tried without water though... do youi have any problems with loose powder after pressing? I think I'll stick to adding (5%) water to dampen the mix for safety.

#5 dan100

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Posted 20 September 2011 - 09:31 PM

density is just an industry standard ,
bp pucks with no dextrin and no water give better results in my op from 1.4-1.9g per cc i saw no difference but the lack of water is asking for a messy time,
pressing pucks with water i have found that you really want to use 5% or less,
5% gave harder grains to break when dried [not a problem if you granulate now][unles it crumbles]
2% and dry the puck/s enables you to smash them and sort them without creating too much unwanted dust.
10% is more like what you would add to pumped star comps.
in the end quality bp run through a screen twice is never too much work.

dan.






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