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lift charge granulation


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#16 maxman

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Posted 31 March 2007 - 06:45 PM

I mill 100g meal and 10g dextrin for 9 hours. I know 10g is quite alot but my powder is really fast after pushing it through a 15 mesh screen. If you're making candles then it needs to be able to stand up to you ramming the delay without the lift being crushed.

1g lift in a 12mm tube will lift a 3/8" star quite high

#17 parabolic

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Posted 31 March 2007 - 06:57 PM

I've had great success making lift granules with 7-8 mesh.
I dont have access to a press.

I use a method like the BP and dextrin way, But in place of dextrin, I use spray starch. (for ironing),

all I do is take a bowl and place some 24hr ball milled BP in it, I then spay a little of spay-starch and mix, I keep mixing and adding spray starch until the mixture starts to 'slightly' clump/cake together, It takes a few goes to get the nack of when its right.
I then press it through the 7-8mesh screen onto newspaper, and leave to dry over night, its ready to use after about 10hrs. or the next day from when its was made.

I find for lifting my 3inch shells, that I need about 3 teaspoons of it,

here is an example of the lift powder shooting a shell. http://sh33p.parabol....com/3shell.avi

#18 Caramanos2000

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Posted 31 March 2007 - 07:02 PM

Mad dibs on the nice shell. I will try this starch spray method. If I post of vid of my Bp will you guys tell me if its ready?

#19 Zinginex

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Posted 31 March 2007 - 07:05 PM

Yeah nice shell. So this spray starch already has a binder in it by the sounds of it? I Might try and get some.

#20 StevenRS

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Posted 03 April 2007 - 12:19 AM

Just a quick question, I have been pressing my Bp though a screen, and when it dries, the grains all stick together in one chunk, do you know what might be happening to me?
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#21 BrightStar

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Posted 03 April 2007 - 12:36 AM

Just a quick question, I have been pressing my Bp though a screen, and when it dries, the grains all stick together in one chunk, do you know what might be happening to me?


Probably just a bit too much water... Try with less, compact your BP + 3% dextrin into a lump and grate it through the screen. You'll end up with a range of grain sizes, some of which will seem very fine, but it's quite usable for lift or burst...

Edited by BrightStar, 03 April 2007 - 12:38 AM.


#22 StevenRS

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Posted 03 April 2007 - 12:12 PM

Ok, thanks it worked :D
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#23 hst45

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Posted 08 April 2007 - 01:23 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.

Over a long period of trial and error, I have standardized my method as follows: I make up a dough-ball of wet meal to the consistency of modeling clay, and run it over a #10 mesh screen at an angle while pressing down firmly. As the doughball moves across the screen, the screen acts as a sort of cheese grater and cuts the dough into granules. By moving the doughball ACROSS the face of the screen, I cut a much finer granule than if I just pushed the compound THROUGH the screen.

Sorry for the long-winded answer, but you can in fact get fine granules made with a coarse screen. To make them more coarse, push more firmly/move the doughball more slowly. It takes a while to get the feel for it, but you can pretty much make the granule any size you want, up to the mesh of the screen.

#24 Caramanos2000

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Posted 08 April 2007 - 07:13 PM

Its what I do also. Why not just try an actual cheese grater?

#25 karlfoxman

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Posted 08 April 2007 - 07:16 PM

I use a cheese grater for making my malese rough powder, works great and I get lovely big granules. I also use it for lifting my large maltese shells, just milled for 2 hours can make a strong lift charge. 200g will lift 7kg with ease.

#26 Caramanos2000

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Posted 09 April 2007 - 02:05 AM

I used the cheese grater and it was SOOOO much easier. Slightly bigger granules, oh it was so satisfying lol.

#27 paul

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Posted 09 April 2007 - 09:35 AM

I use a normal kitchen sieve to granulate my lift charge. (Maybe 1,5mm mesh size)

It´s all up to the water content and the ammount of binder. 3% dextrine/SGRS is perfectly ok. Just knead your black powder ball long enough to distribute the water throughout the mix and activate the binder.

The resulting powder looks like the one in my black powder test video.

Edited by paul, 09 April 2007 - 09:36 AM.

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#28 hst45

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Posted 09 April 2007 - 05:47 PM

Its what I do also. Why not just try an actual cheese grater?

If you have a grater that sizes your granules properly, that that's a great way to go. The only advantage that I see of using a screen is that you have some ability to vary the sizing if you choose to.

As far as a binder, personally I use 5% dextrin. I've been told that this is overkill, and will probably reduces the speed of the powder, but it works for me, and I hate to change a variable when I have all my parameters figured out.

#29 banga

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Posted 10 July 2008 - 12:01 AM

Hey guys, new on here.. I haven't tried this yet but I was wondering if I used my r-candy as a lift charge it wouldn't be too powerful would it? My meal BP burns quite well very close to if not 14 cm per second, but my r-candy (powdered) burns faster, almost double the speed, they both pretty much go up in a puff. I don't have a press or a mill, I just push through a sieve. I'd say the reason the r-candy mix works a little better is due to the sugar binding better with the KNO3.

So anyway, in powdered form obviously the r-candy is a very gaseous and fast burning fuel. Would I get a better lift from it or would it blow out my pvc mortar, which I think is pressure rated to 160-180 psi from memory?

#30 seymour

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Posted 10 July 2008 - 01:27 AM

I see no reason why not to experiment with sugar for firing thins out of tubes, however I would not fire live projectiles (sarshells ect). I think you will find that it is not used for reasons other than that it has not been tried.

For making fireworks I suggest you work on your Black powder, it is obviously not up to scratch if R-Candy burns faster! I suggest you tale a deep breath and plunge into the "making Black powder" thread on this forum. I think you will find that you do not have a good ball mill, or a ball mill at all, or that you are using inferior charcoal. This seems to be the cause of 90% of BP related problems.

One more thing, you should be very careful using PVC for mortars. It is not common practice for safety conscious pyros to use PVC for anything larger than a star gun, and even then one must be careful not to over lift. Certainly one should not be firing shells from a PVC tube.

Edited by seymour, 10 July 2008 - 01:33 AM.

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