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lift charge granulation


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#31 banga

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Posted 10 July 2008 - 02:38 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.


Hey mate, yeah I've definitely had a good look at the BP thread. I don't have willow, but I use red wood for charcoal, it's not optimum but is still quite good. My sulphur, charcoal and KNO3 are super fine and weighed out on digital scales to 0.5 of a gram in accuracy. Obviously minus the fact I don't have a press and I don't have a mill, preparing the BP in the CIA method followed by ricing the powder is the best I can produce. The BP launches quite high, I only wish to see if I can launch it higher...

In regards to launching from PVC mortar, your right, for sure. If it were to explode in the pipe for what ever reason then it would send small sharp pieces of PVC flying. I use protective eye ware and stand at a safe distance in a large open area. I've used pressure pipe for (air guns and gas cannons) before and I believe although no where near as safe as steel mortars, they work quite well, they have had a 100% success rate so far, for all launches I even tested the pipe a few times (safely) buy pushing a shell in way tighter than I would ever normally pack it and each time it blew the shell out.

#32 seymour

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Posted 10 July 2008 - 05:35 AM

You seem to have done your research quite well, and are aware of the dangers involved. While CIA can make perfectly usable BP as you have made, I suggest you buy or build a ball mill if you are serious about a sustained pyro hobby. A ball mill will also allow you to produce Superior charcoal streamers. Depending on where you live a small "rock tumbler" can be ideal, though otherwise, or if you desire a mill that can produce larger batches of black powder and milling-friendly star and rocket compositions building one is the only real option.

Another option which is utilized by the Maltese it to make a small canister shell, spiked and pasted in well, containing only riced powder. The canister shell is used as a lift cup and placed below the shell. Using this method a small amount of relatively poor performing black powder can lift more than the same weight of high quality corned grain.
The monkey leaped off it's sunny perch and flew off into the night sky.

#33 banga

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Posted 10 July 2008 - 05:55 AM

You seem to have done your research quite well, and are aware of the dangers involved. While CIA can make perfectly usable BP as you have made, I suggest you buy or build a ball mill if you are serious about a sustained pyro hobby. A ball mill will also allow you to produce Superior charcoal streamers. Depending on where you live a small "rock tumbler" can be ideal, though otherwise, or if you desire a mill that can produce larger batches of black powder and milling-friendly star and rocket compositions building one is the only real option.

Another option which is utilized by the Maltese it to make a small canister shell, spiked and pasted in well, containing only riced powder. The canister shell is used as a lift cup and placed below the shell. Using this method a small amount of relatively poor performing black powder can lift more than the same weight of high quality corned grain.


Yeah mate, noise from the ball mill would be an issue for me in my current situation. Although I will be looking at one when I purchase a new property. when I can afford one I will be investing in a hydraulic press.

The maltese method sounds good I'll give it a shot, I currently use a lifting cup in the form of a pressure pipe cape, filled with the appropriate amount of BP glued to the shell. This other method would have no weak point, as opposed to my hot glue seal between the cup and the shell, Pressure should definitely be higher this way.

Thanks heaps. I'll let you know how the sugar lift works out, once I test it. The sugar propellant seems to be a lot more gaseous than the BP, it should be interesting.

Cheers.

#34 banga

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Posted 11 July 2008 - 01:00 AM

You seem to have done your research quite well, and are aware of the dangers involved. While CIA can make perfectly usable BP as you have made, I suggest you buy or build a ball mill if you are serious about a sustained pyro hobby. A ball mill will also allow you to produce Superior charcoal streamers. Depending on where you live a small "rock tumbler" can be ideal, though otherwise, or if you desire a mill that can produce larger batches of black powder and milling-friendly star and rocket compositions building one is the only real option.

Another option which is utilized by the Maltese it to make a small canister shell, spiked and pasted in well, containing only riced powder. The canister shell is used as a lift cup and placed below the shell. Using this method a small amount of relatively poor performing black powder can lift more than the same weight of high quality corned grain.


Hey Seymour, I tried the RC mix last night, interesting... The shell was a light 40mm. It launched about 40 - 50m but what surprised me was how quite the launch was, if you wanted stealth launching, the RC lift is the go. Thats only one test you might wish to try with more variables if you were interested but for me I like the sound, so back to my BP.

#35 BlackMesa

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Posted 06 August 2008 - 05:36 PM

Hi there - im sorry to ask a simple question like this but i couldn't find a concise answer elsewhere.

I know how the granulate BP but what i dont understand is the difference between meal powder and granulated powder in terms of burn speed or other reasons such as being better for ramming into the rocket?

I have now managed to make good meal powder and would like to take it up a notch.

Which is better for a blast charge in a small shell, granulated or meal?

Thanks for any feedback

#36 dr thrust

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Posted 06 August 2008 - 07:20 PM

hello!, its simple really, the idea for granulating is you get grains that have a large surface area with air pockets around them so the flame can travel much faster though the mass, than a pile of meal where the it would burn from the top down.

the reason for granulating in a rocket comp has no effect on performance, its simply done to make the comp more easy to handle, with straight bp comps you get lots of dust whilst ramming and funnels can get blocked where the grains are easy to pour, often they are riced/granulated with oil,Vaseline etc to give a soft rocket fuel grain which is less likely to crack and cause a cato

#37 Bonny

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Posted 06 August 2008 - 07:22 PM

Hi there - im sorry to ask a simple question like this but i couldn't find a concise answer elsewhere.

I know how the granulate BP but what i dont understand is the difference between meal powder and granulated powder in terms of burn speed or other reasons such as being better for ramming into the rocket?

I have now managed to make good meal powder and would like to take it up a notch.

Which is better for a blast charge in a small shell, granulated or meal?

Thanks for any feedback



You will want granulated powder for lifting or bursting shells. The reason is that flame travels faster through grains using the airspace. A fine powder creates a fire block which slows the flame down.
I use -10+20 mesh for lifting 1" shells and in some mines and -4+10 mesh for 3" shells and up. I may try a 3" with the finer size one of these days...
For bursting 1" shells I have used everything...meal/granulated powder/meal-d, whatever is "leftover" and handy when I'm making them.
For larger shells to save on weight and chems you will want to use meal coated rice hulls or whatever (I use vermiculite)

#38 Shake

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Posted 06 August 2008 - 08:33 PM

For larger shells to save on weight and chems you will want to use meal coated rice hulls or whatever (I use vermiculite)


Hey Bonny;

Out of curiousity, what method do you use to coat the vermiculite? And are you happy with the results. I've read and am in the progress of using rice krispies and am anxious to try them.

Chris
Fireworks are paint brushes for the night sky...with a few bloody huge BOOMS thrown in for good measure!

#39 digger

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Posted 06 August 2008 - 10:17 PM

Hey Bonny;

Out of curiousity, what method do you use to coat the vermiculite? And are you happy with the results. I've read and am in the progress of using rice krispies and am anxious to try them.

Chris


Rice Krispies are great. They are easy to do in a star roller aren't they.
Phew that was close.

#40 Bonny

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Posted 07 August 2008 - 02:00 PM

Hey Bonny;

Out of curiousity, what method do you use to coat the vermiculite? And are you happy with the results. I've read and am in the progress of using rice krispies and am anxious to try them.

Chris


I've never tried rice crispies, but a lot of poeple use them so they must be good. I bought a bag of vermiculite last year and still have a lot left, so I won't be changing anytime soon. The vermiculite has been working well for me.

I make 4:1 or 5:1 BP to verm, more or less using the method off cannonfuse website:
-weigh out the vermiculite, soak in warm water,spin in washing machine ~20sec, put in a ziploc bag, add BP and shake.
I use BP +5% dextrin for first 3 increments only (making 4:1) then the last increment is BP only (no dextrin) as it will adhere to the dextrin already on the vermiculite. I found that in IPP book.

I haven't tried the vermiculite in my star roller, but it is a tire so I think being so light, the vermiculite may turn all the way around and spill all over the place.

#41 Labs2008

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Posted 10 August 2008 - 10:38 PM

Could I use the 4 to 10 mesh grains for less than 2" shells. I am new to making bp and my first attempts with 10-20 mesh grains did not workout so well for lift.

#42 dr thrust

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Posted 10 August 2008 - 10:44 PM

hello the fact that your new to making bp, tells a tale, how do you make your bp? how long milling, which charcoal, ect

#43 Labs2008

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Posted 11 August 2008 - 01:09 AM

hello the fact that your new to making bp, tells a tale, how do you make your bp? how long milling, which charcoal, ect


I use dusting sulfur 90% pure
I have made my own pine charcoal
I also have some lump wood charcoal
I have spectricide stump remover which according to the msds is 100% kno3
It is like sugar consistancy I mill it fo about 8 hours and it becomes fine clay,flour like powder.
I have also milled my charcoal for over 24 hours just to make sure it was as fine as i could get it.
The dusting sulfur is then milled with the charcoal for 6 hours. I then mill the 3 together with 2% dextrin by weight from 2 to 8 hours.
I only make about 50 gram batches at a time. I use a mill with a 6 inch id and 6.625" od It holds around 25 lbs of media which consists of 12 lb lead muzzle shot .50 caliber. 5 lbs of fishing sinkers the 1oz size. 2lbs of us nickles and the rest is brass balls of about 4 oz each. When the mill is running it is actually relaxing sounding like a good rain shower on the roof.

I rice the powder with 2% dextrin by weight and let it sit in a safe place for at least 24 hours. I used a 10 mesh screen at first but things seemed consistantly slower than expected. I tryed lauching a few dummy shells of around 1" diameter but no matter how much lift i put in the shell would only climb about 10 -20 feet tops. I made he shells loose enough to slide in the mortar similar to a commercial shell i also made shells to fit tighter in mortar which is 12" long.

I was thinking of ricing a batch with my 4 mesh kitchen strainer. and seeing if it made better lift.

thanks

#44 knackers

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Posted 11 August 2008 - 02:14 AM

g`day labs,,..what ratio of constituents are you using,, 75 /15/ 10 ?.... your prob could lay in your media,, that much lead rubbing together is sure to heavily contaminate your bp,, and perhaps try cutting out the the 4% dextrin.. 25 pounds of media in a 6`` diameter tub sounds alot,

Edited by phill 63, 11 August 2008 - 02:23 AM.


#45 Labs2008

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Posted 11 August 2008 - 02:24 AM

g`day labs,,.. your prob could lay in your media,, that much lead rubbing together is sure to heavily contaminate your bp,, and perhaps try cutting out the the 4% dextrin.. 25 pounds of media in a 6`` diameter tub sounds alot, perhaps also your media is choked and is not tumbling freely,



Good day too you as well. I only use 2% dex by weight and the jar is 10" long it is filled half way with media. Are you sure i should lower my media charge?. maybe just the fishing sinkers should go they are temporary until I can afford some more hardened lead. it would still be at 20 lbs. the empty jar itself ways 8.7 lbs". it is rotating at a speed of about 90 rpm and the media can clearly be heard rolling and dropping in the container.(Like rain on a tin roof). The lead was all ran with clay and charcoal for 3 days before i used it for any production. The lead is a nice shiney silver color instead of the dull dark gray it was at first.
I use 75/15/10. I actually mix my charcoal and sulfur together in the 15/10 by weight. then when i make bp I just add 25 % c+s with 75% kno3

Edited by Labs2008, 11 August 2008 - 02:28 AM.





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