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Techohead

Member Since 16 Oct 2007
Offline Last Active Jun 21 2009 09:09 AM
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Topics I've Started

Pyrotechnic Tutorials

14 September 2008 - 02:33 AM

hello to all,
i was just making a thread here so that i could let everyone know that I'm trying to start a small scale website with tutorials on it on how to make black powder, aerial shells, stars and starmines, things like that, so that whenever we come across all the inexperienced pyro's out there that still need to pick up all the basics, we can just send them a link. i don't know about others, but i have a youtube account that gets several emails a day asking simple things like how do rocket work, how does black powder work, how this, how that... so anyway, the website URL is:

www.techohead.pcriot.com

it's a free website and hence it has limitations to what content is allowed and there's only about 100MB to use. i've put a few advertisements down the bottom left of the page so that if i raise enough money i might be able to buy a proper url like pyrotutor or something like that, but that all depends on how it works out.
at the moment there's hardly any content on my site but i'll add a bit to it every day and in a few weeks it should ahve some really useful stuff. everyone feel free to visit (click on some adds if you'r feeling charitable) and use this thread to give me suggestions, or maybe send me tutorials that you've written entirely by yourself on how something is made.

thanks in advanced for any help or advice you good people of UKPS have to offer.

KNO3 grades and applications

08 June 2008 - 02:36 AM

Hello to all,
i hate to have to bring up something i'm sure has been done to death, but finding certain bits of information on this forum is proving difficult at times. for the last 6 months i have been using tech grade to make all my pyrotechnics compositions, and have been getting excellent performance out of everything.
recently my supplier went out of business due to false declaration of dangerous goods in the national postage system. i have recently been looking all around the internet for another AUSTRALIAN supplier, but have not been able to find anyone who sells tech grade KNO3 in less than 1 tonne quantities. i have however found a source for farm/agriculture grade KNO3 in 25Kg bags. this KNO3 is much more affordable but price was never an issue anyway. i would like to know what the typical percentage purity would be for this type of KNO3, and will i still be able to get the same sort of performance from my black powder and other compositions? any information anyone can give me on the subject is much appreciated,'
thanks in advanced,
techohead.

black powder rockets exploding after storage

10 April 2008 - 11:23 AM

hello to everyone,
a few months ago i made a design for my own black powder rocket, using my own black powder fuel, bentonite plugs and i lathed a complex profile onto a set of tools for ramming. the first rocket i made this way was hugely successful, reaching over 100 meters in height. i replicated it, again and again. i was making 10 per week and enjoying the delights of the effects i could lift with them. when terror struck in the form of a pyrotechnic ban enforced by my family. i decided if i was not allowed to 'make' any pyrotechnics for a couple of months, i'd better make a few last rockets and use them sparingly. i made 15 rockets, fitted some with visco ignition, some with electric ignition, and i left them lying ontop of my dvd player for almost a month. tonight i finally removed 4 of them from the dvd player, fitted a header on one, and went out to light them. the first rocket, electrically lit, blew it's nozzle out immediately. i put it down to 'the electric igniter must have been jammed to tightly in the nozzle'. i lit a visco fuse lit rocket, in which nothing blocked the nozzle at all, and the same thing still happened. huge explosion, and the shell of the rocket would go about 10 meters high, then fall back down. i noticed a trange thign was happening. not only was the nozzle failing and blowing out, so was the end plug!

now in a rocket, pressure will accumulate until the weakest point fractures, and the pressure discharges. if the nozzle blew out, the pressure should have escaped out of the open ended rocket, but for it to then continue and also blow out the top plug, there must have been astronomical internal pressures. i lit a third and fourth rocket, and all the same.

so far my only theory is that over time the moisture in the air has caused the chemicals in the black powder to 'precipitate' together, creating a much faster burning black powder, even though the powder was already as fast as i could make it by milling. if any has any ideas i'm open to hear them. unfortunately the remaining 11 rockets are now just ground reports or something of the likes. but i need to find out how to prevent it ever happening again.

Incredible Milling Phenomina

25 January 2008 - 12:50 AM

i've been running my ball mill for the last 35 hours, with 500 grams of black powder inside, and 80 pieces of my milling media. just now i opened up the mill to take out the finished powder, and noticed that there was no powder, just 80 1" marbles. in the centre of each of these marbles was a piece of my milling media. the marbles are rock solid, and i cannot even break them open in a clamp. so as to get my milling media back, i set the marbles on fire in one of the largest fireballs i've ever made. this got my milling media back to opperational standard, however the inside of teh milling drum tooo is covered in rock hard BP. i cannot get it out, but cannot burn it out as that would cause an explosion fatal to me, and i somewhat like being alive. can anyone tell me why every surfact inside my mill is covered in rock hard bp, and are there any suggestions on how to get it out withoug filling it with water, because i hope to save any powder i can, and more importantly, what caused it, so i can avoid it happening again. all i can think of is the really high humidity at the moment may have caused the powder to start clumping, as it may become the slightest bit moist.

Spolette Formulas

22 January 2008 - 02:37 AM

hello again to all.
just a few weeks back i made my first ever 2/3" aerial report, using homemade black match for time delay fusing. they were reliable, so i took it a step further and made my first 1" aerial shell, with the same fusing in it, however they were starting to prove less reliable... so i thought about what to do next, when i came up with the concept of the spolette, without knowing it was already a widely used concept. i made a random formula to try, and found that it gave me a 1.5 second delay when 1" long, so thats what i used. it's been 100% reliable now, and i've made atleast 8 of these shells. now i want to make 1.5" shells, but the spolettes are starting to get fiddly, because they just aren't long enough.

so i started experimenting again, using different powder trying to get a 2" long spolette to burn in 1.5 seconds. i just cannot achieve it. with air float BP milled for 40 hours, it burns for 3 seconds, with corned BP it burns in 0.5 seconds. i cannot find anything to pack in my spolette, that burns 2" in 1.5 seconds. throw your formula's and ideas at me.